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Rochester Institute of Technology Rochester Institute of Technology RIT Scholar Works RIT Scholar Works Theses 2-1-1992 Vibration analysis of a thin moving web and its finite element Vibration analysis of a thin moving web and its finite element implementation implementation Gavin Chunye Liu Follow this and additional works at: https://scholarworks.rit.edu/theses Recommended Citation Recommended Citation Liu, Gavin Chunye, "Vibration analysis of a thin moving web and its finite element implementation" (1992). Thesis. Rochester Institute of Technology. Accessed from This Thesis is brought to you for free and open access by RIT Scholar Works. It has been accepted for inclusion in Theses by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected].

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Rochester Institute of Technology Rochester Institute of Technology

RIT Scholar Works RIT Scholar Works

Theses

2-1-1992

Vibration analysis of a thin moving web and its finite element Vibration analysis of a thin moving web and its finite element

implementation implementation

Gavin Chunye Liu

Follow this and additional works at: https://scholarworks.rit.edu/theses

Recommended Citation Recommended Citation Liu, Gavin Chunye, "Vibration analysis of a thin moving web and its finite element implementation" (1992). Thesis. Rochester Institute of Technology. Accessed from

This Thesis is brought to you for free and open access by RIT Scholar Works. It has been accepted for inclusion in Theses by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected].

VIBRATION ANALYSIS OF A THIN MOVING WEB

AND ITS

FINITE ELEMENT IMPLEMENTATION

by

GAVIN CHUNYE LIU

THESIS ADVISOR: DR. H. GHONEIM

VIBRATION ANALYSIS OF A THIN MOVING WEBAND ITS

FINITE ELEMENT IMPLEMENTATION

GAVIN CHUNYE LIU

A Thesis Submitted

in partial Fulfillment

of the

Requirements for the Degree of

MASTER OF SCIENCE

In

Mechanical Engineering

ROCHESTER INSTITUTE OF TECHNOLOGY

Rochester New York

FEBRUARY 1992

Approved by:

Dr. H. Ghoneim (Advisor)

Dr. J. S. Torok

Dr. M. Kempski

Dr. Charles Haines

I, Gavin C. Liu, do hereby grant Wallace

permission to reproduce my thesis In whole

reproduction by Wallace Memorial Library will

for commercial use or profit.

ii

Memorial Library

or in part. Any

not to be used

ACKNOWLEDGMENTS

To my parents, and my wife, who have provided me the

supports and encouragement that I needed for all my work.

To Dr- Hany Ghoneim, my thesis advisor, I wish to express my

deepest gratitude for his boundless encouragement and

helpfulness, and his warmest friendship.

To Dr- Joseph Torok, who taught me finite element

formulation, and other graduate courses, my thanks for his

helps and admiration for his knowledge.

To Dr. Charles W. Haines, my academic advisor, my

appreciation for providing me with invaluable guidance during

my college years.

And finally to the members of my thesis defense committee, I

appreciate very much for the time they spent reading and

evaluating my work.

in

ABSTRACT

Equations of motion (lateral and axial) of an axially

moving web are developed based on the Newton's Second Law and

the Euler-Bernoul 1 i thin beam theory- The equations of motion

in the axial direction are solved by using the fourth-order

Runge-Kutta Method. The fourth-order, partial differential

equation for the lateral motion is solved using Galerkin's

finite element method and the Three-point Recurrence Scheme.

Effects of the flexibility of the end-supports, the weight of

the web, the axial web speeds, the eccentricities of the

rollers, and the applied torque to the web-roller system are

studied .

IV

TABLE OF CONTENTS

NOTATION vi

SYMBOLS vi i i

LIST OF FIGURES ix

1 INTRODUCTION 1

2 THEORY and DERIVATION 4

2.1 Governing Differential Equation 4

2.2 Supplementary Differential Equation 11

3 FINITE ELEMENT IMPLEMENTATION 14

3 . 1 Spatial Approximation 14

3.2 Time Approximation 18

4 RESULTS and DISCUSSION 20

4. 1 Free Vibration 25

4.2 Vibration of Constant Web Speeds 34

4.2.1 Effect of The Web Speed 34

4.2.2 Effect of Phase Shift Between

The Two Eccentricities of The Rollers ... 39

4.3 Vibration Due To The

Sudden Changing in The Applied Torque 44

5 CONCLUSION 50

REFERENCE 52

APPENDIX A 55

APPENDIX B 63

APPENDIX C 72

NOTATION

A cross-section area of the web

a lateral acceleration of element dx

B!,B2 viscous damping at rollers

b width of the web

b the global boundary condition vector

be

the element boundary condition vector

b*, boundary condition entries

c kinematic damping

[C] the global damping matrix

[C]e

the element damping matrix

Dl5D2 diameters of rollers

d thickness of the web

E modulus of elasticity of the web material

e eccentricity of unbalance rollers

Fy the resultant force of element dx in the

lateral direction

F force vector that includes the f and b

f the global external force vector on the web in

lateral direction

f the distributed external force on the web

fe

the element external force vector

fe, entries of external force matrix

g gravitational acceleration ( ss 9.81 m/s2)

h length of an element

I area moment of inertia of the web

<Ji > J2 polar moment of inertia of the web

K,Kl5K2 stiffness of the end-supports

k axial stiffness of the web

k, flexural stiffness of the web

[K] the global stiffness matrix

[K]e

the element stiffness matrix

1 length of the web

vi

[M] the global mass matrix

[M]*

the element mass matrix

m mass per unit length of the web

m0 unbalanced mass of the rollers

p tension of the web

Q , (X )shear force

R residual of the approximation

T applied torque

Tj frictional torque

V axial velocity of a material point on the web

Vx axial velocity of a material point at x/1 = 1

V2 axial velocity of a material point at x/1 = 0

u displacement in axial direction

w displacement in lateral direction

We

the element lateral displacement as a

function of time only

W the global lateral displacement as a function

of time only

X,Y fixed coordinates

x,y moving coordinates

/? Galerkin's coefficient ( /? = |)

7 Galerkin's coefficient ( 7 = |)

A a constant of a stiffness matrix

p density of the web material

strain

r equivalent axial force

a1,a2 angular accelerations of the rollers

Wj , w2 angular velocities of the rollers

0j , 02 angular displacements of the rollers

<?! , #2 angular displacements of the unbalanced mass

6 deflection angle of element dx

ip{ Hermite's interpolation functions (shape

functions)

(p{ the weight functions

vu

SYMBOLS

8 infinitesimal increment

A small increment

[ ] matrix

summation

| | determinant of a matrix

( ) derivative with respect to space

vm

LIST OF FIGURES

Figure Caption page

1 A simplified model of the web-roller system 2

2 An element of the moving web 4

3 Free body diagrams for end conditions 10

4 Free body diagrams for derivation of supplementary equations of axial motion 1 1

5 Model of" rigid-flexible"

setup 21

6 Model of"flexible-flexible"

setup21

7 Initial displacement for"rigid-flexible"

setup24

8 Initial displacement for"flexible-flexible"

set-up24

9 Response of free vibration for the"rigid-flexible"

setup at x/1 = 1.0 26

10 Response of free vibration for the"rigid-flexible"

setup at x/1 = 0.8 27

11 Response of free vibration for the"flexible-flexible"

setup at x/1 = 1.0 28

12 Response of free vibration for the"flexible-flexible"

setup at x/1 = 0.8 29

13 Response of free vibration for the"flexible-flexible"

setup at x/1 = 0.0 30

14 Response of system for the"flexible-flexible"

setup due to the weight

of the web at x/1 = 0.8 32

15 Displacement profile of the web with and without the weight of

the web at t = .501 sec 33

16 Response of the system at for the"rigid-flexible"

setup with

w = 20 rad/sec (V = 5 m/s) at x/1 = 0.8 36

17 Response of the system at for the"rigid-flexible"

setup with

w = 40 rad/sec (V = 10 m/s) at x/1 = 0.8 37

18 Response of the system at for the"rigid-flexible"

setup with

w = 60 rad/sec (V = 15 m/s) at x/1 = 0.8 38

19 Response of the system for"flexible-flexible"

setup with V = 10 m/s and

phase shift of

0"

at x/1 = 0.8 40

20 Response of the system for "flexible-flexible"

setup with V = 10 m/s and

phase shift of

90

at x/1 = 0.8 41

21 Response of the system for"flexible-flexible"

setup with V = 10 m/s and

phase shift of

180

at x/1 = 0.8 42

IX

22 Displacement profile of the web for three different phase angles at three

instants (t = .302, 1.201, 1.801 sec) 43

23 Plot of the changing torque for the transient vibration analysis 44

24 Response of the web tension due the changing torque 46

25 Response of the angular velocities of rollers 1 it. 2 due the changing torque 46

26 Response of the system for the"flexible-flexible"

setup due the changing

torque at x/1 = 1.0 47

27 Response of the system for the"flexible-flexible"

setup due the changing

torque at x/1 = 0.8 48

28 Response of the system for the "flexible-flexible"setup due the changing

torque at x/1 = 0.0 49

A-l Diagram for the derivation of equation (2.13) 56

A-2 Approximate function for the first and the last nodes 61

B- 1 Model for calculation of the natural frequencies of the roller-supports 64

B-2 Model for calculation of the natural frequencies of the web 66

B-3 Model for calculation of the natural frequencies of the web under the

assumption of rigid supports 67

1 INTRODUCTION

Vibration control on moving continua, such as moving

magnetic tapes, paper tapes, band-saw blades, pulley belts,

coating film, and other applications, is an active research

area for many manufacturing industries. Naguleswaran and

Williams [1] studied the vibration and stability of a moving

string excited paramet r ical ly by the periodic vibration of

tension in the string. Ulsoy and Mote [2] studied the

vibration of wide band-saw blades by modeling the blades as

moving plates. Mote and Naguleswaran [3] did research on the

linear free vibration of an axially moving thin beam using an

exact solution, Galerkin solution, and flexible band solution.

Chonan [4] investigated the steady state response of an axially

moving strip under a transverse point load. Effects of

t ranslat ional velocity on the natural frequencies and modes of

an axially moving beam between fixed ends were investigated by

Simpson [5] using the Euler beam theory. Wickert and Mote [6]

analyzed the response of an axially moving continua between two

fixed point using a second-order model and a fourth-order

model. Manor and Adams [7] analyzed the response of an elastic

beam moving with constant speed across a drop-out at a smooth

rigid foundation using the Euler-Bernoul 1 i beam theory.

Analysis of the vibration due to the tension variation of

moving continua together with effects of friction between the

moving continua and rollers were done by Whitworth and Harrison

[8] . Gottlieb [9] studied the non-linear vibration of a

constant-tension string. Daly did some studies on the effect

of air pressure on a moving web [10] . Brandenburg studied the

effect of the frictional force between the web and the roller

by assuming the web is stretchable and obeys the Hooke 's law

[11] . Most of these previous studies were done under the

assumption of rigid supports.

Figure 1 shows the model of the web-roller system to be

investigated in this study. The moving continuum is a thin

web, and it is modeled as a continuous elastic beam. The

driving and the driven mechanisms are simplified as rollers

which are supported by linear springs. Note that the

deflection of the roller-supports in the horizontal direction

are not taken into consideration in this investigation.

A, E, I

M J,

vv/v.v

Ml h

Figui* 1. A amplified Model of the web-roller syvtem.

Due to many factors such as the flexibility of supports,

the velocity of the web, the imperfection (eccentricities of

the rollers) of the machinery, the non-linear material

properties of the moving web, the frictional force between the

moving web and the stationary machine parts, and the

aerodynamics effects (for high speed only), vibration control

of the moving web is a very complicated process. For the sake

of simplicity, the effects of the non-linear material

properties, the frictional force, and the aerodynamics are not

taken into account in this work. Studies of the web are done

only on the effects of the flexibility of supports, the

velocity of the web, and the imperfection of the machinery (the

unbalance on the rollers) . Newton's second Law and Euler-

Bernoulli beam theory are applied in the formulation of the

flexural vibration of the continuous beam. The Fourth-order

Runge-Kutta method is employed to solve the equations of motion

in the axial direction. The Galerkin's finite element method

and the Three-point Recurrence Scheme [12] (the Newmark

Recurrence Scheme [13]) are used for the solution of the

flexural vibration.

2. THEORY and DERIVATION

The development of the basic differential equations

(governing and supplementary equations) in this study is based

on Newton's Second Law and Euler-Bernoul 1 i theory (the thin

beam theory) [14] . The governing differential equation for the

flexural vibration of the beam (in this case, the beam is a

flexible web) is developed first. Then supplementary

differential equations are derived for the axial motion of the

web .

2.1 GOVERNING DIFFERENTIAL EQUATION

An element of length dx of the web is shown in Figure 2

together with all forces and moments.

Figure 2. An element of the moving web.

Applying Newton's Second Law ( Fy = ma ) to the free

body diagram in Figure 2 gives

-psinfl + Q + fdx - (Q + |Qdx)<5X

7

+ (P + ^dx)sin(0 + Mdx) = ma (2.1)

Under the assumption of small 9, the following

relationships are valid.

sin0 as tan0 = ^ (2.2)

sin(0 + gdx) a 0 + Mdx

tan0 + f^dx>5x

= fe + ^dx (2-3)

Substituting equations (2.2)-(2.3) into equation (2.1),

taking into consideration that m = pAdx, and a =

2-Wancj

Dt2

neglecting the second order terms yield

f ' S + " - >* C*.4>

where p is assumed to be time but not space dependent for

s impl ic ity .

Summing the moment about point 0 (Figure 2) , and assuming

the moment of inertia of the element to be negligible gives

Mo = _M + fdx^ + (M + |Mdx) _ (Q + |9dx)dx = 0 (2.5)

Once again, neglecting the second order terms, equation

(2.5) reduces to

or

Mdx - Qdx = 0

= (2.6)

Substituting equation (2.6) into equation (2.4) results in

* - (!5) + p S = m6xv5x

PiwDt2 (2.7)

Applying the Euler - Bernoulli beam theory (the thin be<

theory) [14], M(*,t) = EI()W(*'t}

, to equation (2.7) gi

<5x

ves

f - A_[EI(,)d-Sli] + p X() = pA g^ (2.8)5x <5x (5x

v.5x' Dt"

Assuming the cross-sectional area of the web is constant

along the web, the moment of inertia I(i) is equal I, and

equation (2.8) can be rewritten as

EI^ + PA) + f = pA a^fix dx Dt(2.9)

Where

and

E

I

P

f

P

A

. .the lateral displacement of the centroid of

element dx,

..the modulus of elasticity of the web material,

..the cross sectional area moment of inertia,

. .the axial force (tension) in the web,

..the lateral distributed force per unit length,

..the density of the web material,

. .the cross sectional area of web.

6

r\2

The term ^-^ in equation (2.9) is the material derivative

of w with respect to time [15] , and it can be expressed as:

Dfw_

Dw n

{2 10^1Dt2 Dt1^ Dt

> ^,iUj

where

Dw_ 6w , 6_w x

Dt St"*"

<5x St

or

where V is the axial velocity of a material point on the web,

and it is a function of both time and position, x. It is

defined, at any given instant, as

V = V2 + (Vx - V2) 2f (2.12)

where Vx and V2 are the web velocity at the right end (x/1 =

1.0) and the left end (x/1 = 0.0), respectively, and they are

defined as

Vx = ^ Ul (2.13)

and

V2 = u,2 (2.14)

where Dj and D2 are the diameters of the rollers #1 and #2,

respectively, uil and w2 are the angular velocities of the

rollers #1 and #2, respectively, and they can be found from the

supplementary differential equations.

Substitution from equation (2.11) into equation (2.10)

with further expansion yields

7

Pi = Pi + 2vf- + &g +SW |w|Vv (215)Dt2

St StSx. oxot8x.2 6x.6x

v J

for small deformation

W=k^ (2-16)

where e, which is the strain [16] in the web due the web

tension p, is defined as

e = & (2.17)

Derivation of equation (2.16) is shown in Appendix A.

Substituting equations (2 . 15) - (2 . 17) into equation (2.9),

and rearranging terms yields

m<5!w

+ 2c^ + k^- + rpi + Af^ = f (2.18)S-t2 6t,8x 6x4 <5x2 *x

where m = pA (2.19)

c = pVA (2.20)

k = EI (2.21)

r =pAV2

-

p (2.22)

and A =pArSV

+ _V_*E) (2.23)

The term fx can be defined as

ot

SV _D2 6u2 fD1 Sux D_2 Su^.

x r9 94n

Tt~

It+ ^2 6t 2 6t ; 1 <^.^;

where and -^can be found from the supplementary

r5t Ot

differential equations.

The boundary conditions of equation (2.18) are derived

from free body diagrams in Figure 3. Figure 3 shows that the

continuous beam is postulated to be simply supported at each

end. For simplicity, two rollers are assumed to be identical

with unbalanced m0e, and are supported by two identical elastic

springs with stiffness K as shown in Figure 3. The unbalance

m0e in each roller is assumed to be identical. It should be

pointed out that the phase angle between the two eccentricities

is zero in Figure 3. However, the phase angle could be any

value .

By summing all forces in the lateral direction at each end

of the free body diagram one at a time, the boundary conditions

[14] are found to be

1) At the left end:

n - FTo"3w(:M)|y(o,)

~

ti"7x3~

l(o,)

= Mw(o,t) + Kw(o,t) + m0ew22sin# - m0ea2cos# (2.25)

where K = Kx = K2 in this study.

2) At the right end:

n - FT^'1'0!yC'*>

~

<5x3l(M)

= - Mw(i,) - Kw(i,t) - niQeu^sin^ + mgeo^cosd} (2.26)

Where m0 is the unbalanced mass.

m0ew3

m0ee*j

fBoewj

nioei

F i gu re 3Ffee body diagram for derivation of end conditions.

For simply-supported beams, the ends

take any moment at any time, i.e.

of the beams do not

8 W(r,t)i_ Q

M(o,t)~ Ei

6x2 l(o,t)~ u (2.27)

M(i,t)

= EI62w(>,0|5x2 'l('.t)

= 0 (2.28)

Equation (2.18) is the equation of motion of the element

dx in the lateral direction with the boundary conditions as

defined by equations (2 . 25)- (2 . 28) . The equations of motion in

,1direction for providing

the values of V, p, ^,and

the axial

dpdt

are to be derived in Section 2.2,

10

2.2 SUPPLEMENTARY DIFFERENTIAL EQUATIONS

In order to solve the fourth order partial differential

equation (equation (2.18)), variables V, p, |^, and-jS in the

axial motion have to be found first. Figure 4 shows the free

body diagrams of the two rollers of the web-roller system.

.5m

roller #2 roller #1

Figure 4 Free body diagram of rollers for derivation of

supplementary differential equations

Summing the moment about the center of roller #1, Oj ,

gives

or

J^ = T - B^ -

p

8ui1 _ \_

Di

Di

w- ^( T - BlWl

-

P^ ) (2.29)

where Jj ... the polar moment of inertia of the roller #1,

11

Bj ... the viscous damping at the roller #1,

Wj . . . the angular velocity of the roller #1,

Dx ... the diameter of the roller #1,

T ... the applied torque at the driving roller.

Summing the moment about the center of roller #2, 02 ,

gives

or

J2"2 =

P^-

T, B->u>2w2

St J2^ p2( P-y-

T,- B2w2 ) (2.30)

where J2

B2

w2

D,

the polar moment of inertia of the roller #2,

the viscous damping at the roller #2,

the angular velocity of the roller #2,

the diameter of the roller #2,

the fictional torque at the driven roller.

Assuming that

p = k Al (2.31)

where k is the axial stiffness of the web in this study and Al

is the change in the length of the web due to the different

angular displacement of the two rollers. Under the assumption

of no slipping between the rollers and the web, Al is defined

as

2Al = 0, -

2Uz (2.32)

where Qx , 02 are the angular displacements of rollers.

Substitution from equation (2.31) into equation (2.32)

yields

P = k( Sfe, - ^e2) (2.33)

Taking the derivative of equation (2.33) with respect to

12

time gives

g= j|( DlWl - D2u,2 ) (2.34)

Equations (2.29), (2.30), and (2.34) represent the

supplementary differential equations that are required to

evaluate the values of V, p, ^, and -jx in the axial directionot dt

of the web. Initial conditions for equations (2.29), (2.30)

and (2.34) are to be defined in the chapter of Results and

Discussion in this paper.

Solution of equation (2.18) is to be approximated by

applying the finite element method with the boundary conditions

that are established in equations (2 . 25) - (2 . 28) . The

supplementary differential equations are to be solved by the

fourth-order Runge-Kutta method. The finite element

formulation of equation (2.18) is to be presented in the next

chapter .

13

3. FINITE ELEMENT IMPLEMENTATION

Solution of the partial differential equation (equation

(2.18)) is accomplished in two stages: (1) Spatial

approximation which is achieved by using the Galerkin's method

(the Weighted Residual Method). (2) Time approximation which is

approached by using the Three-point Recurrence Schemes [12]

(the Newmark recurrence scheme [13] ) . The first stage

approximates the partial differential equation (2.18) by a set

of simultaneous, ordinary differential equations, and the

second stage approximates the set of ordinary differential

equations by a set of linear algebraic equations, which can be

solved at each time step. Such a procedure, which finds the

spatial approximation first, then the time approximation, is

known as a semi -d iscrete approximation [17] .

3.1 SPATIAL APPROXIMATION

The Galerkin's method is used for the approximation of the

partial differential equation.

Assuming the solution of equation (2.18) for each

element, wc(x, ) ,

to be

we(*,0 = 1>l*)j WV);, N = 4 (3.1);'=i

where xp(x) is the shape function within each element, We(*)j is

the nodal lateral displacement of the element, and N is the

order of the interpolation function. For simplicity, ip(x)j and

14

We(t);- are to be written as tp- and WO, respectively, in the later

descr ipt ion .

Substituting equation (3.1) and its derivative with

respect to time and space into equation (2.18) gives

N N N

mEV-jWe;. +

2ct/>;.' We;- +kl>;""

W%j=i j=i i=i

+rV;" W%- + At/y

W%- - f = R ^ 0 (3.2).

j=i j=i

Note that expression (3.2) is no longer exactly equal to zero

since the approximate representation for we(x,t) is used. Hence R

is called the residual of its original equation.

Setting the integral of a weighted residual of the

approximation over the whole domain of each element to zero

results in

J"

<t>{ R dX = 0 (3.3)o

where </>, are the weight functions (which, in general, are

not the same as the shape function ipj) .

Substituting equation (3.2) into equation (3.3), and after

some manipulation, gives

(m iM,-dX) '\f'j + (2c V/^dX) W%j=i o j=i o

+ (kE ^ W'dx) w%. + (rE / w^'dx)vi'

jj=l 0 j=l o

+ (AE / V-/^dX) We,. - / <^,fedX = 0 (3.4)j=i o o

15

Integrating the third term of equation (3.4) by parts, it

becomes

(k ^/'"dX)we; = (k V^"dX)Wi" M " *i (3-5)

i=i o j=i o o

Nwhere M = k xp

We;- is the bending moment of each element

i=i

N

and Q = k V/" We;- is the shear force of each element.

;'=i

Substituting equation (3.5) into equation (3.4), gives

Me{jW%. + Ce(j

W%- + K'{jW%- = f% + b% (3.6)

where

and

Ke0- = Keoij + KeUj + K%,;. (3.7)

M8,- = | rPjm <, dX (3.8)

o

Ce{j = /V c <p{ dX (3.9)

Keotj =jV' k ^" dX (3.10)o

K^j=jV'

T +i dX (3-11)0

Ke2ij= jV A *,- dX (3.12)

o

f. = J*f 0,- dX (3.13)

o

andb\- = [M 0,'

- Q <,]

"

(3.14)o

In this study, the Hermite cubic interpolation functions

(shown in Appendix A) are adopted for the shape function.

16

Applying the Galerkin's method, the weight functions <p{ are the

same as the shape functions xp);. The corresponding element

matrices, the external force vector, and the boundary condition

vector are evaluated based on the Hermite cubic interpolation

functions in Appendix A.

The global equations (a set of ordinary differential

equations) are obtained via the standard assembly method [18],

i.e.

[M]e We

+[C]e We

+[K]e We

=fe

+be

or [M] + [C] W + [K] W = f + b (3.15)

where n is the number of elements, W is the global lateral

displacement vector, and [M] , [C] , [K] ,f , and b are the global

mass matrix, damping matrix, stiffness matrix, external force

vector, and boundary condition vector, respectively.

It should be pointed out that the global boundary

condition vector, b, has zero components except for those at

the end nodes (the first and the last nodes), i. e.

b = ( Q(0), - M(0), 0, 0,..., 0, 0, -Q(i), M(/) ) (3.16)

where the shear forces of the first and the last nodes are to

be determined from equations (2.25) and (2.26), and the moments

of the first and the last nodes are zero according to equations

(2.27) and (2.28).

Equation (3.15) is the global ordinary differential

equation which needs further approximation in the time domain.

17

3.2 TIME APPROXIMATION

Equation (3.15) is exactly the same as equation (21.1) in

"The Finite Element Method"

by 0. C. Zienkiewicz [12] . The

Three-point Recurrence Scheme (the Newmark Recurrence Scheme)

was used by Zienkiewicz for the time approximation of equation

(21.1). Following Zienkiewicz 's derivation procedure, the time

approximation of equation (3.15) takes the form of

[[M] + 74t[C] + /?4t2[K]] Wt+1

+ [-2 01] + (l-27) *t[C] + (i-2/?+T)^t2[K]] W,

+ [[M] - (l-7)*t[C] + (i+/?-7)at2[K]] W(_x +FAt2

= 0 (3.17)

where [M] , [C] ,and [K] are defined as in equation (3.15) ,

F is

the force vector that includes both the global force vector and

the boundary condition vector, 0 and 7 are the Galerkin's

coefficients for time approximation, and the subscripts t+i, i,

and (-1 indicate three consecutive instants. The values of 0

and 7 are | and |, respectively, which are evaluated by

Zienkiewicz .

According to Zienkiewicz's derivation, the F is

interpolated as

F = F(+1/3 + F((i-2/?+7) + F(_1(|+/?-7) (3.18)

Equations (3.17) and (3.18) are the final forms for the

solution of equation (2.18), and they are used in the finite

18

element program. The values of W(-1 , Wt , Ft-1 , F, , and Ft+1, which

are used to start the program, are described in the program in

Appendix C. This chapter described the whole process of

solving equation (2.18) starting from implementing the element

matrices, to assembling the global matrices, and then to

finding the final form of approximation. The numerical results

of equation (3.17) for this study are shown in the next

chapter .

19

4. RESULTS and DISCUSSION

All results are generated by three computer programs:

AXIAL, WEB1 , and CONVER. The AXIAL program, which was written

by Dr. H. Ghoneim, utilizes the fourth-order Runge-Kutta method

to solve the supplementary differential equations of the axial

motion, and it has been updated to include the investigation of

different web speeds and different phase angles between the two

unbalanced rollers. The AXIAL program has to be run first to

provide the WEB1 program with the necessary values of V, -^ , p,

and - at each time step. The WEB1 program is a finite element

program, which was originally written by Dr. H. Ghoneim in

FORTRAN code. The WEB1 program utilizes the final

approximation equations (equations (3.17) and (3.18)) with the

data of V, j^ , p, and-r^

from the AXIAL program to solve the

partial differential equation (equation (2.18)) for the

flexural vibration of the web-roller system. The WEB1 program

has been updated to incorporate the gravitational force of the

web. The CONVER program is used to convert the time domain

response from the WEB1 program into the frequency domain. The

CONVER program calls a sub-program, FFTRF, from the IMSL

library of the RITVAX system [19]. The FFTRF employs the Fast

Fourier Transform algorithm. All programs are listed in the

Appendix C.

The web-roller system is investigated for two different

setups (Figure 5 and 6) :

1) A"rigid-flexible"

setup ( Figure 5, ), where one

roller-support is treated as a rigid support and the other is

20

out

WW.

F igu re 5 a simplified model of the"rigid-flexible"

web-roller system.

Figure 6A simplified model of the

"flexible-flexible"

web-roller system.

21

Studies are conducted for the following cases:

1. Free vibration of the web when it is not axially

moving ( V = 0 ) for both"rigid-flexible"

and

"flexible-flexible"setups. This is done to verify

the validity of the computer programs and to study

the effect of the flexibility of the roller-supports.

Effect of the weight is also considered for the

"flexible-flexible"

setup when the web is not moving.

2. Vibration of the web when it is moving with constant

speeds. Two factors are investigated:

a. The effects of different web speeds for the

"flexible-rigid"setup.

b. The effects of the phase shift between the

eccentricities of the rollers for the "flexible-

flexible"

setup.

3. Vibration of the web under the effect of a sudden

change of the applied torque at the driving roller-

The following values of the system parameters are adopted

for the investigation.

p =103

kg/m3, Dx = D2 = 0.5 m,

E = 4 x109

pa, Jx = J2 = 8.283kgm2

,

d = 1.25 x10-4

m, Bi = B2 = 0.5 Nms ,

b = 1.35 m, I<! = K2 = 7.36 x109

N/m,

1 = 1.52 m, Mt = M, = 8.27 x103

kg,

22

b = 1.35 m, K! = K2 = 7.36 x109

N/m ,

1 = 1.52 m, M! = M2 = 8.27 x103

kg,

k = 4.44 x105

N/m, m0e = 10 kgm .

where d, b, 1, and k are the thickness, width, length, and

axial stiffness of the web, respectively.

Other parameters, that are needed for obtaining the

results of this paper from the WEB1 and AXIAL program, are

listed as the following:

start time = 0.0 second,

end time = 1.93 second,

time increment = 0.001 second,

and number of elements = 21 elements.

However, the values of the above parameters can be changed to

different values.

Results are displayed in Figures 9-22, and 24-28. Note

that for Figures 9-14, 16-21, and 26-28, each figure is

composed of three graphs: a, b, and c. Part a of each figure

represents the temporal response of the system in the time

domain, while parts b and c show the corresponding response of

the system in the frequency domain for the linear and

logarithmic amplitudes respectively. Logarithmic plot for all

frequency responses of the system are displayed to give better

visibility of the peaks of the frequency spectrum.

23

Hl> WW

\-L.

Tcsua.iMu nsirrcn

c- >

Figure 7 A aimplified model of the"rigid-flexible"

web-roller system.

cajuamw narwm

<H

F i gu re 8 A simplified model of the"flexible-flexible"

web-roller system.

24

4.1 FREE VIBRATION

The following parameters are considered for the free

vibration studies of the web-roller system when the web is not

in motion (wx =w2

= 0 rad/sec), and the pre-tension, p = 200 N.

The system is excited from rest via a linear, initial

displacement in the lateral direction as shown in Figure 7 and

8. The values of the displacement at the left and the right

ends are w(o,o) = 0 m, and w(/,o) = 4E-6 m, respectively.

Samples of the free vibration results of the web-roller

system are shown in Figures 9 and 10 for the"rigid-flexible"

setup, and in Figures 11, 12, and 13 for the "flexible-

flexible"setup. Figure 9 shows the response of the system at

the position of x/1 = 1.0. Figures 9b, and 9c show the natural

frequency of the roller-support is about 140 Hz, which crudely

agrees with the natural frequency of the roller support.

Analytical results (shown in Appendix B) of the natural

frequencies of the roller-supports and the web are found to

verify the numerical solution obtained from the program.

Figures 10b and 10c show the numerical values of the natural

frequencies of the web from the programs. Those numerical

values are in excellent agreement with the analytical results

in the Appendix B. Figures 10b and c also indicate very

clearly that the vibration of the web-roller system is

dominated by the natural frequency of the roller-supports.

Comparison of Figure 11, 12 with Figure 9, 10 respectively

indicates that the flexibility of the left end has very little

effect on the responses of the web-roller system. Figure 13

shows the responses of the system at x/1 = 0.0, and it

indicates that the natural frequency of the left roller-support

to be 140 Hz. That is because the two roller-supports are

25

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exactly the same for the "flexible-flexible"setup. An

interesting phenomenon is observed in Figure 13a. The left

roller support, which is initially at rest, is gradually

picking up vibration that is transferring from the right roller

through the web. This is happening because the web-roller

system is acting as a predominantly two degrees of freedom

system with the two rollers linked together by a very soft

spring (the web) as shown in Figure 8. Since the stiffness of

the web, in this analysis, is far smaller than those of the

roller supports (calculations of stiffness for support and web

are shown in Appendix B) , the energy transfer from the right

roller to the left roller is happening in an extremely slow

manner. (Note that after 2 sec, the left roller picked up a

vibrating amplitude of10-8

m which is about 450 times smaller

than the vibrating amplitude at the right roller.) The

significant difference between the stiffness of the roller-

supports and the flexural stiffness of the web is the reason

why most previous studies in this field were done under the

assumption of rigid supports.

When the web is not in motion (V = 0 m/s) ,the damping of

the system is equal to zero as represented by c in equation

(2.17). The beating phenomena (Figure 10a, and 12a) occur when

the system with very little damping (in this case the system

has no damping) is subjected to the excitation frequency (the

natural frequency of the support) that is very close to the

thirteenth mode natural frequency of the web [20] (analytical

solution for the natural frequencies of the roller-supports and

the web are shown in Appendix B) .

Responses at the position of x/1 = 0.8 due to the weight

of the web are shown in Figure 14. Due to the downward

direction of gravitational force, the temporal response (Figure

14a) of the web shifts toward the negative side. Comparing the

plots in Figures 14b and 14c with the plots in Figure 12b and

12c, reveals that the vibrating amplitude is bigger for the web

31

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with the weight than for the web without the weight. The

weight of the web tends to promote the lower frequencies.

Figure 15 shows the displacement profile of the web, with

and without the weight of the web, at the instance of t = 0.501

second after the right end has been released from the initial

displacement of 1E-4 meter. The lower curve is the

displacement profile of the web with the weight of the web, and

the other curve is the displacement profile of the web

excluding the weight.

RcturaL shape of the ueb at t-

.501 sec

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the web at t = .501 sec

Upper curve: without the effect of the weight.

Lower curve: with the effect of the weight.

33

4.2 VIBRATION OF CONSTANT WEB SPEEDS

The web speeds, that are going to be used in this section,

are actually the axial velocity of a material point on the web

(equations (2 . 12) - (2 . 14) ) since the angular velocities of the

rollers are the same.

4.2.1 Effects of the Web Speed

The system is studied, when the initial displacements at

the left and the right ends are w(o,o) = 0 m, and w(*,o) = 4E-6 m,

respectively, for the following cases:

1) V = 5 m/s (w1 =u>2

= 20 rad/s) ,and p = 160 N (constant) ,

2) V = 10 m/s (u*! =w2

= 40 rad/s) ,and p = 200 N (constant) ,

3) V = 15 m/s (u1 =u>2

= 60 rad/s) ,and p = 240 N (constant) .

Figure 16, 17, and 18 show the responses of the system for

the"flexible-flexible"

setup with the web speeds of 5 m/sec ,

10 m/sec, and 15 m/sec at x/1 = 0.8, respectively. A closer

look at the Figures (b, and c of Figures 16, 17, and 18)

reveals that the natural frequencies of the web decrease as the

web speed increases. That is because the stiffness of the web

decreases as the web moves faster in the axial direction.

Three factors contribute to the stiffness of the web-roller

system as described by equations (3.7). These factors are: 1)

the flexural stiffness of the web, k(EI) in equation (3.10),

2) the axial velocity and tension of the web, as represented by

t in equation (3.11), and 3) the time rate of change of the

34

equation (3.12). For constant web axial speed and tension, the

third factor drops out (A = 0). As illustrated in Appendix B,

the value of r decreases with increasing web axial speed, and

consequently, the total stiffness of the web decreases as well.

It should be pointed out that the axial speed introduces a

"kinematic"

damping to the system through the parameter c in

equation (2.18). As the speed increases, the damping factor, c,

(equation (2.20)) increases. It appears, however, from the

figures that the change in c with the speed is too small to

introduce any significant effects.

Again, the beating phenomenon occurs in all the three

cases as one of the higher natural frequencies ( the 13 ,the

14'A, and the16"1

mode for V = 5 m/sec, 10 m/sec, and 15 m/sec

respectively) modulates with the natural frequency of the rotor

support .

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38

4.2.2 Effects of Phase Shift Between The Two

Eccentricities of The Rollers

Investigation on the effects of 0, 90, and180

phase

shift between the two eccentricities of the rollers is done

when the web speed is 10 m/sec (wj = w2 = 40 rad/s) ,and the

tension of the web is 200 N.

For the "flexible-flexible"

system, the phase angle of the

eccentricities of the rollers plays an important roll in the

vibrating modes of the moving continua [1] . Figures 19, 20,

and 21 show the responses of the system with phase angles of

0, 90, and 180, respectively. Comparison of the results of

the three cases shows that the0

phase angle-difference case

produces the smoothest vibration as shown in Figure 22a. For

this case, since both end-rollers move together, only the lower

modes are excited, and the higher modes are relatively

suppressed as shown in Figure 19b. That also explains why the

amplitude of vibration of the first peak is slightly higher for

the 0 case than the other two cases(90

and 180) . For the

90

and180

phase difference, the opposite movement of the two

rollers excites the higher modes and triggers the natural

frequencies of the roller supports as demonstrated in Figures

20b, 20c, 21b, and 21c. It appears that there is no

significant difference between the responses for the90

and

the180

phase shift case. These suggest that beyond a certain

phase shift the degree of shift does not have a significant

influence on the dominant vibrating frequencies.

Figure 22 shows the displacement profiles of the web for

the three different phase angles (0, 90, and 180) at three

different instants(t = .302 sec, t = 1.201 sec, and t = 1.801

sec). Clearly, for the0

phase angle case, thel"

mode

dominates the rest (Figure 22a) as a result of the synchronized

motion of the end rollers, while in the other two cases (Figure

22b, 22c) higher frequencies are well excited.

39

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43

4.3 VIBRATION DUE TO THE SUDDEN CHANGE IN THE APPLIED TORQUE

Studies of the effect of a sudden change in the applied

torque from 70 NM to 110 NM (Figure 23) are done when the web

is initially moving at 10 m/sec (wt = w2= 40 rad/s) and has an

initial tension of 200 N. The phase angle in this case is 0.

?8-

,8-

cr

O 5

Toroue vs TLms

i | I I I I I I i i i | i i i i . . I r r r i i r i | I I I I | i I I I | I I I r | . . i I | i .

0.2 0.1 0.6 O.S l 1. 2 1.1 1. 6 I.S 2 2.2

Time (sec)

Figure 23

Figures 24-25 show the responses of tension, and the

angular velocities of rollers due to the sudden change of the

applied torque. As the applied torque is suddenly increased,

the tension of the web follows almost instantaneously and

increases to an average steady state value of 280 N (Figure

24). Because of the assumption of an elastic web, the steady

44

state tension in the web is oscillatory. As for the angular

velocities of the end rollers, they follow "sluggishly"and

increase very slowly (Figure 25) . This is attributed to the

high inertia of the rollers which resists any sudden change in

speed and delays the response.

Figures 26, 27 and 28 show the responses of the system,

for the"flexible-flexible"

setup due to the sudden change of

the applied torque at three points on the web. Figures 26a and

28a demonstrate that the amplitudes of vibration of the roller-

supports are gradually increasing. This is because the angular

velocities of both rollers are gradually increasing and

consequently the unbalanced forces are also gradually

increasing. The same, but less obvious, can be observed about

the web vibration in Figure 27a. Plots b and c of Figures 26,

27, and 28 clearly show that the response of the system is

dominated by the excitation frequency of the rotating

unbalanced rotors.

45

Figure 24 Response of tans, on due to the sudden charge

of torqu* wlUi t_h i_rii.li.al voLu of 200 N

Figure 25a

f?MD008 of W2 due to the sudden chanat'

of Corqu w<.th ch Lni.ti.ol. voLu of 40 rod/sac

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46

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49

5. CONCLUSION

From the foregoing analysis, it can be concluded that the

web-roller system is affected by the flexibility of the roller

supports, the weight of the web, the axial speed of the web,

the phase shift between the unbalance masses, and the sudden

change of the applied torque on the driving roller.

1) Flexibility of the driven roller-supports has very little

effect on the free vibration of the system for a short period

of time. However, for a long run, the free vibration indicates

that the energy transfer phenomenon (beating phenomenon)

between the two roller-supports can occur.

2) Increasing the speed of the moving web increases the

"kinematic damping", which reduces the vibration. However, it

turns out that the increased damping is too small to be

significant .

3) Increasing the speed of the moving web reduces the overall

lateral stiffness of the system and consequently decreases the

values of the natural frequencies of the web. This indicates

that there is a higher possibility for one of the natural

frequencies of the web to match the angular velocities of. the

rollers (excitation frequencies).

4) Increasing the speed of the web (which means increasing the

angular velocity of the rollers) amplifies the unbalanced

forces at the rollers and consequently introduces more

vibration to the system.

50

5) The phase shift between the unbalanced forces of the rollers

excites the higher modes of vibration and aggravates the

vibration of the system.

6) A sudden increase in the applied torque introduces

fluctuation in the web tension.

This work can be extended to study the effects of other

factors such as the viscoelast ic ity of the web, the change in

the dimensions of the web and the material properties, the

aerodynamic forces on the web, and the frictional force between

the web and the rollers.

51

REFERENCES

[1] S. Naguleswaran and J. H. Williams, "Lateral vibration

of band-saw blades, pulley belts andlike,"

International Journal of Mechanical Sciences, 1968, Vol.

10, pp 239-250.

[2] A. G. Ulsoy and C. D. Mote, Jr., "Vibration of wide band

sawblades,"

Transactions of the American Society of

Mechanical Engineering, Series B, Journal of Engineering

for Industry, 1982, Vol. 104, pp 71-77.

[3] C. D. Mote, Jr. and S. Naguleswaran, "Theoretical and

experimental band sawvibrations,"

Transactions of the

American Society of Mechanical Engineering, Series B,

Journal of Engineering for Industry, 1966, Vol. 88,

pp 151-156.

[4] S. Chonan, "Steady state response of an axially moving

strip subjected to a stationary lateralload,"

Journal

of Sound and Vibration, 1986, Vol. 107, pp 155-165.

[5] A. Simpson, "Transverse modes and frequencies of beams

translating between fixed endsupports,"

Journal of

Mechanical Engineering Science, 1973, Vol.15, ppl59-164.

[6] J. A. Wickert and C. D. Mote, Jr., "Classical vibration

analysis of axially movingcontinua,"

Transactions of

the American Society of Mechanical Engineering, Journal

of Applied Mechanics, 1990, Vol. 57, pp 738-744.

52

[7] H. Manor and G. G. Adams, "An elastic beam moving with

constant speed across adrop-out,"

International Journal

of Mechanical Science, 1983, Vol. 25, No. 2, pp 137-147.

[8] D. P. D. Whitworth and M. C. Harrison, "Tension

Variation in pliable material in productionmachinery,"

Applied Mathematical Modeling, 1983, Vol. 7, June, pp

189-196.

[9] H. P. W. Gottlieb, "Non-linear vibration of a constant-

tensionstring,"

Journal of Sound and Vibration, 1990,

Vol. 143, No. 3, pp 455-460.

[10] D. A. Daly, "Factors Controlling Traction Between Webs

And Their CarryingRolls,"

Tappi, 1965, Vol. 48, No. 9,

pp 88A-90A.

[11] G. Brandenburg, "The Dynamics of Elastic Webs Threading

a System ofRollers,"

Newspaper Techniques, 1972,

September, pp 12-25.

[12] 0. C. Zienkiewicz, "The Finite ElementMethod,"

3rd

edition, McGraw-Hill Book Company (UK) Limited, 1977, pp

581-589.

[13] D. S. Burnett, "Finite Element Analysis From Concepts to

Applications,"

Add i son-Wesley Publishing Co., 1987,

pp 526-531.

[14] S. S. Rao, "MechanicalVibration,"

Addison-Wesley

Company, Inc. 1984.

53

[15] T. J. Chung, "Continuum Mechanics", Prentice Hall, New

Jersey, 1988.

[16] F. P. Beer and E. R. Johnston, Jr., "Mechanics of

Materials,"

McGraw-Hill Book Company, Inc. 1981, p42 .

[17] J. N. Reddy, "An Introduction to The Finite Element

Method,"

McGraw-Hill Publishing Company, Inc. 1984,

p 50.

[18] D. L. Logan, "A First Course In The Finite Element

Method", PWS-KENT Publishing Company, Inc, 1986.

[19] "User's Manual: IMSLMath/Library,"

IMSL Company, 1989,

Version 1.1, January, p 707.

[20] M. L. James, G- M. Smith, J. C. Wolford and P. W-

Whaley, "Vibration of Mechanical and Structural system:

With MicrocomputerApplication,"

Harper k Row,

Publishers, New York, 1989.

54

APPENDIX A

Al DERIVATION OF EQUATION (2.13) IN CHAPTER 2

A2 SOME DETAILS OF THE FINITE ELEMENT IMPLEMENTATION

55

Al DERIVATION OF EQUATION (2.13) IN CHAPTER 2

Figure A-l shows a section of undeformed web, O'o ,and a

section of deformed web oox with a moving coordinate system xy

in the space of a fixed coordinate system XY. Note that

section O'o has been straightened as section Oo for better

understanding of the diagram.

-**

k

-J\

oEjSsrrEai

Figure A-l

At time equal to zero, point A is measured from system XY

with Z, so Z is time independent. After a period of time, At,

the moving system xy moves from 0, the origin of fixed system

XY, to o, and point A moves to A'. For the sake of simplicity,

the motion of the web is considered in the x-direction only.

At any time, the following relationship holds:

Z + u = r + x

56

(Al.l)

where Z is the material coordinate of point A, r is the

distance traveled by the origin of the moving system, u is the

displacement of point A, and x is the coordinate of point A'.

Taking the time derivative of equation (Al.l) gives

dZ , i5u_ i5r , i5x /a-i oa

dt+

It~

St+

St{AL.^)

where the first term ^ is zero. Hence, equation (A1.2) can be

rewritten as

& =

K~ & <A1-3>-

Equation (A1.3) gives the velocity of a material point.

Considering the left hand side of equation (2.13) ,

= <&> <A1-4>

Under the assumption of small deformation, substitution of

equation (Al . 3) in to equation (A1.4) gives

8W_ __8_

(8u_

Sr\

<5x

~

<5x ^-St 6tJ

jL fiu\ _ A. (f>'r\~

<5x^<5t;

-5xKSt}

- A. ff>n\-

-5x^St}

- A. (>u\~

Stkc5x;

The term ( ) is zero because r is time dependent only.

<5xy8ty

57

A2 SOME DETAILS OF THE FINITE ELEMENT IMPLEMENTATION

A2-1 The Hermite interpolation function and the element

matrices

Hermite cubic interpolation functions are used to

interpolate the spatial approximation, and they take the form

as :

^ = 1 -

3(g)2

+2(g)3

V>2 = x ~ T" +

,2 3

(A2.1)

(A2.2)

V>3 =

V-4 =

3(g)2 2(g)3

h+

h2

(A2.3)

(A2.4)

here h is the length of each element

Substitution of equation (A2 . 1) - (A2 . 4) and their

derivatives into equation (3 . 8) - (3 . 13) ,all element matrices

are defined as the following:

r\M~\ e mh

[M] -

420

156 22h 54 -13h

22h4h2

13h

54 13h 156 -22h

13h-3h2

-22h

4h'

(A2.5)

58

[C]e= 2c

-.5 .lh .5 -.lh

-.lh 0 .lh

-.5 -.lh .5 .lh

hi"60

lh ^i-.lh 0

60

(A2.6)

[KoJ'= h

12 6h -12 6h

6h4h2

-6h

2h2

12 -6h 12 -6h

6h2h2

-6h

4h2

(A2.7)

[KJ6=

30h

36 3h -36 3h

3h4h2

-3h

-36 -3h 36 -3h

3h -3h

4h*-

(A2.8)

[K2]e=

30h

-36 -33h 36 -3h

-3h 3hh'

36 3h -36 33h

-3h

h2

3h

(A2.9)

59

m hfj2

h

6

(A2.10)

h

'6

wherefe

in equation (A2.10) is the distributive, external

force along an element of the web. In this study, the only

external force, that is taken into account for one case, is the

gravitational force of the web. As a result, the external force

acting on an element is

fe= Ml (A2.ll)

where p is the density of web, A is the cross-sectional area of

the web, and g is the acceleration due to gravity.

With equation (A2.ll), the external element force matrix

is expressed as

MMgh

h

6

(A2.12)

h

'6

60

A2-2 The end conditions and its approximated function

The only boundary conditions that needed to be evaluated

are those at the first and the last nodes, because those end

conditions between elements will cancel each other out when the

global matrices are being assembled.

Figure A-2 shows the approximate functions for the

solutions at both ends, and those approximate function and

their derivatives take the values of

<*1 = 1, V = o at x = 0 (A2.13)

4>2 = 0,<p2'

= i at x = 0 (A2.14)

K-i = i-K-i'

= o at x = 1 (A2.15)

4>n = 0,4>n'

= 1 at x = 1 (A2.16)

F.rst Nod*

F igure A-2 Approximate function of first and last nodes.

Applying the approximate function equat ions (A2 . 13) - (A2 . 16)

61

to equation (3.14)

b,- = [M<6,.'

- Q <6,-] (3.14)

for the first and the last elements at the first and the last

nodes gives

bi -

(0)

M(0)

br-l =

b =

1(0

M(')

The shear forces Q and the moments M can be found by

usingequations (2 . 21) - (2 . 24) .

62

APPENDIX B

Bl . Calculations of natural frequencies of the roller-supports

and the lateral stiffness of the web.

B2 Analytical solution for the natural frequencies of web

B3 Calculation of r with w = 20, 40, 60 rad/sec.

63

Analytical calculations of the natural frequencies of the

supports, the lateral stiffness of the web, the natural

frequencies of the web, and the value of r with different

angular velocities are carried out in this appendix.

Bl . Calculations of natural frequencies of the roller-supports

and the flexural stiffness of the web.

The system is modeled as shown in Figure Bl .

VV^

7777T777 777777777

Figure Bl Model for calculation of n*tuial frequmeki of

roller-support*.

The energymethod [15] is used for the formulation of the

equat ions .

M 0

0 M

yi

y'2

+

K + kf -kf

-kfK + k; Y2

= 0 (B.l)

or

64

1 0

0 1

yi

y2

+

r + s -s

-s r + s

yi

y2(B.2)

[K] e<j

r + s -s

-s r + s

(B.3)

where = I7 and s = -d-

M M (B.4)

Finding the value of kf (the flexural stiffness of the web)

E (the modulus of elasticity of the web) is 4E9 Pa,

I (the area moment of inertial of the web)

l =(1.35)

q.25E-4)

= 2.1973E_13m4

k, =3EI

=3(4E9)(2.1973E-13)

= 7.50g2E_4 N/r5 l3 1.523

The [A] matrix is

[A] = [M]-1^] = [K]e,

r + s -s

-s r + s

(B.5)

the eigenvalue A of [A] will give the natural frequencies

of the system. The natural frequency of the system is

Wn = ^A (B.6)

+ s- A - s

+ s - A

= 0

or (r + s -

A)2-

s2

= 0

(B.7)

(B.8)

Solve equation (B.7) for A

65

Ax = r

A, = r + 2s

so

Wi = -jr

or nfx =

^ = 943.38rad

sec

150 Hz

where nf means natural frequency.

w9 \v + 2s = ^889963.724 + 2(9.0788E-8)

* 943.38 rad/sec

nf2 = 150 Hz

B2 Analytical solution for the natural frequencies of the web

Consider the problem described in Figure B2 with tension p

in the beam, the governing differential equation of the beam is

EI<S4w

5x4 K<5x2"

H~8t2PH + Pk-52w

_ 0

HTTTmrm

A, B, I, P

(B.9)

muwmn

F igu re B2 Model for calculation of natural frequencies of

the web.

66

Equation (B.9) is the same as equation (2.15) when V is

zero .

Because of the significant difference between the

stiffness of the end-supports and the flexural stiffness of the

web (K = 7.36E9 N/m, k; = 7.5082E-4 N/m), the system of Figure

B2 can be model as the system in Figure B3 .

1gu re 3 Model for calcuIation of natura, frequencies Qf

the web under the assumption of rigid supports .

The simple support boundary conditions for the system in Figure

B3 are

1) at the left hand side:

w(o,t) = 0, and Elf^(o.t) = 0.^

ox

67

2) at the right hand side:

w(*,o = 0, and EI^(/,t) = 0,8^

Assuming the solution of equation (B.9) to be

w(i,t) = W(r)(A1sinwt + Bjcoswt) (B.10)

where W(x) is a function of space only, Al and Bx are constants

which can be found from the initial conditions, and the w is

the natural frequencies of the web in rad/sec. Substituting

equation (B.10) and its time derivative into equation (B.9)

gives

PTd4W nd2W

dx dxpAw2W = 0 (B.ll)

By assuming the solution of W to be

W(s)= ^ (B.12)

the auxiliary equation of equation (B.ll) can be obtained:

r -

-z-t

p_e2pAw2

_ 0EI

(B.13)

Solving equation (B.13) for gives

*ai,*aa +2EI

- \ 4E2I2+

pAw

~ET (B.14)

Equation (B.12) can be rewritten as (with absolute value of f2)

W, x = C,cos2x + C2sinf2x + C3cosh^x + C4sinh^x (B.15)\X)

68

where C^ , C2 , C3 and C4 are to be determined by the boundary

condit ions .

Applying the left hand side boundary conditions to

equation (B.15), constant C1 = C3 = 0. Hence equation (B.15)

becomes

wO)= C2sin2x + C4sinh^x (B.16)

Applying the right hand side boundary conditions to

equation (B.16) gives

and

C2sin2l + C4sinh^l = 0

- C222sin2l + C^i'sinh^l = 0

(B.17)

(B.18)

Equations (B.17) and (B.18) are a set of simultaneous

equations for unknowns C2 and C4 ,and they can be put into the

matrix form as

sin2l

-22sin2l

sinh^l

^sinh^l

C, 0

0

x and 2 can be found by setting the determinant of the

coefficient matrix equal to zero.

(sinhf1l)(sint2l) = 0 (B.19)

Since sinh^l > 0 for all values of c^l ^ 0, the only roots for

equation (B.19) are

<t2l = mr n = 0, 1, 2, (B.20)

69

Thus the natural frequencies of the system in Figure B3 (using

equations (B.14) and (B.20) after algebraic manipulation) are

Uln

12VAav" +

_2r,TI

2 i 2n pi

ir2EI

(B.21)

The natural frequencies for the first few modes are found

when p = 1000kg/m3

, 1 = 1 . 52 m, E = 4E9 Pa, I = 2.1273E-13

m4

(calculation is shown previously in this Appendix), p = 200 N,

and A = 1.6875E-4m2

, and listed on Table Bl .

Table Bl

mode

n

Frequenc ies

(Hz)

0 0

1 11.32

2 22.65

3 34.0

4 45.3

5 56.64

6 68.0

7 79.31

8 90.65

9 102.0

10 113.35

11 124.71

12 136.08

13 147.45

70

B3 Calculation of r with w = 20, 40, 60 rad/sec .

The relationship of ulf w2 and p is described in equation

(2.25), (2.26), and (2.30) in Chapter 2. If the values of ws

are changed, the value of p would also be changed accordingly.

Assuming ul and w2 are the same, equation (2.30) is zero.

Inputting 20, 40, and 60 rad/sec into equation (2.25) for

w2 ,the values of p are 160, 200, and 240 N, respectively.

Converting the values of angular velocities of 20, 40, and

60 rad/sec into linear velocities, the linear velocities are

5, 10, and 15 m/sec, respectively.

Using equation (2.24)

r =pAV2

-

p (2.24)

for V = 5 m/sec (w = 20 rad/sec) ,and p = 160

r =103

(1.6875E-4)(52) - 160 = -155 N;

for V = 5 m/sec (u = 20 rad/sec) ,and p = 160

t =103

(1.6875E-4)(102) - 160 = -183 N;

for V = 5 m/sec (w = 20 rad/sec) ,and p = 160

r =103

(1.6875E-4)(152)- 240 = -202 N.

71

APPENDIX C

All programs, which are used for this work, are listed in

this appendix.

CI PROGRAM WEB1

C2 PROGRAM AXIAL

C3 PROGRAM CONVER

72

PROGRAM WEB1

73

00001

00002

00003

00004

00005

00006

00007

00008

00009

00010

00011

00012

00013

00014

00015

00016

00017

00018

00019

00020

00021

00022

00023

00024

00025

00026

00027

00028

00029

00030

00031

00032

00033

00034

00035

00036

00037

00038

00039

00040

00041

00042

00043

00044

00045

00046

00047

00048

00049

00050

00051

00052

00053

00054

00055

00056

00057

* *

*

*

*

*

*

*

* *

C

c*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

**********************************

*

FINITE ELEMENT PROGRAM *

**********************************

*

MOVING WEB *

WITH VIBRATING BOUNDARIES *

*

**********************************

THIS PRRGRAM IS USED TO CALCULATE THE ELEMENT STIFFNESS MATRIX,DAMPING MATRIX, AND MASS MATRIX OF THE WEB, TO CALCULATE THE

GLOBAL STIFFNESS MATRIX, DAMPING MATRIX, AND MASS MATRIX OF

THE WEB BASED ON THE ELEMEMT MATRICES, AND IT IS ALSO USED TO

TRANSFORM A SYSTEM OF DIFFERENTIAL EQUESTIONS IN A FORM OF:

[GM]*YDD + [GC]*YD + [GK] *Y BD

INTO A SYSTEM OF LINEAR EQUATIONS IN A FORM OF

[A]*Y + [B]*Y1 + [D]*Y0 - R

SUB-PROGRAM DESCRIPTION:

ELEMENT . . . PROVIDES ELEMENT MATRICES

GLOBFX. . . .ASSEMBLES FIXED GLOBAL MATRICES

GLOBVR. . . .ASSEMBLES VARIABLE GOLBAL MATRICES

NUMARK. . . .CLACULATES THENEWMARK'

S COEFFICIENT [A], [B] , [D]MULT PREPARES ARRAYS FOR ITERATION.

SEIDEL OR GUAS FINDS THE APPROXIMATION.

OUTPUT. . . .WRITES DATA FOR PLOTS.

VARIABLES DESCRIPTION:

HT THE THICKNESS OF THE WEB

WD THE WIDTH OF THE WEB

LNGTH . . . THE LENGTH OF THE WEB

RO THE DENSITY OF THE WEB

EE MODULUS OF ELATICITY OF THE WEB

DY INITIAL DISPLACEMENT

G GRAVITY

DT TIME INCREMENT

BETA. . . .GALERKIN'SCOEFFICIENT

GAMMA. . .GALERKIN'SCOEFFICIENT

IX MASS MOMENT OF INERTIA

H LENGTH OF ELEMENT

SLOPE ... SLOPE OF THE LINEAR INITIAL DISPLACEMENT

VI AXIAL VELOCITY OF WEB

Y(I) . . ..Y-DIRECTION

DISPLACEMENT ARRAY

M ELEMENT MASS MATRIX

C ELEMENT DAMPING MATRIX

K1,K2,K3. . .ELEMENTSTIFFNESS MATRICES

EF ELEMENT FORCE MATRIX

74

00058

00059

00060

00061

00062

00063

00064

00065

00066

00067

00068

00069

00070

00071

00072

00073

00074

00075

00076

00077

00078

00079

00080

00081

00082

00083

00084

00085

00086

00087

00088

00089

00090

00091

00092

00093

00094

00095

00096

00097

00098

00099

00100

00101

00102

00103

00104

00105

00106

00107

00108

00109

00110

00111

00112

00113

00114

*

*

*

*

*

*

*

*

*

*

*

GM GLOBAL MASS MATRIX

GC GLOBAL DAMPING MATRIX

GK1 , GK .. GLOBAL STIFFNESS MATRICES

GF GLOBAL FORCE MATRIX

VI,V2. . .LINEAR VELOCITIES OF ROLLER 1 & 2

V1D,V2D. .LINEAR ACCELERATION OF ROLLER 1 & 2

Vin CONSTANT INPUT VELOCITY

P TENSION OF WEB (CONSTANT OR VARIABLE)PD TIME RATE OF TENSION IN WEB

P0 PRE-TENSION (FOR FREE VIBRATION ANALYSIS ONLY)

PARAMETER (NB-6, N-4, NN-168)

INTEGER CONTROL

REALM A(NN,NB) ,B(NN,NB) ,D(NN,NB)REALM GM(NN,NB) ,GC(NN,NB) ,GK(NN,NB) ,GK1(NN,NB) , GF (NN)

REALM M(N,N) ,C(N,N) ,K1(N,N) ,K2(N,N) ,K3(N,N) , EF (N)

REALM R (NN) , R0 (NN) , Rl (NN)REALM Y(NN) , Y0 (NN) , YI (NN) ,V0(NN) ,SIG(NN/2)

REALM ZER(NN) , LNGTH, IX,P0,Vin

DIMENSION IBD(4) , FBD (NN) ,FF(3,4) ,EN(3,NN)*

COMMON/MATDIM/RO,EE,AREA, IX,HT,P, G,P0,Vin

COMMON/NEWMRK/BETA, GAMMA

COMMON/DELTAS /DT, H

COMMON/SEIDEL/ERRCRT,MAXITR

COMMON/CONTR/NFRQ, IWRT, CONTROL* TITLE

WRITE (6, 600)600 FORMAT (///10X, 'VIBRATION OF A MOVING WEB',

+ /10X,-

--'

)* INITIALIZATION

DO 10 I-1,NN

R(I)-0.0

R0(I)-0.0

Rl ( I ) -0 . 0

ZER(I)-0.0

DO 10 J-1,NB

A(I, J) -0.0

B(I, J) -0.0

D(I, J) -0.0

GM(I, J) -0.0

GC(I,J)-0.0

GK(I, J) -0.0

10 END DO

* BASIC DATA

READ ( 5 ,* ) CONTROL

READ(5,*) P0, Vin

READ (5,*) HT,WD, LNGTH,RO,EE,G

READ (5,*) DT, BETA, GAMMA

READ (5,*) ERRCRT,MAXITR

READ (5,*) TERM, KODBND,KODLIN, KODINT

READ (5,*) NFRQ,IWRT

*

AREA-HT*WD

IX-WD*HT**3/12.0

NE-NN/2-1

75

00115 H =LNGTH/NE

00116 N4=NN-4

00117 T = DT

00118 NBOUND=4

00119 KOUNT=2

00120 IFRQ-1

00121 STOP=-1.0

00122 ZERO=0.0

00123 *NEWMARK'S METHOD FORMULATION ON P584 OF THE FEM

00124 *BY O. C. ZIENKIEWICZ.

00125 DT2=DT*DT

00126 A2=0.5-2.0*BETA+GAMMA00 127 A1=0 . 5+BETA-GAMMA

00128 *. . . .WRITE DATA

00129 WRITE(6,610)00130 610 FORMAT (/5X, 'INPUT DATA',/ 5X,

'

)00131 WRITE'6,620) RO,EE

00132 620 FORMAT //5X, 'MATERIAL: ',00133 1 /5X, 'DENSITY =',1PE12. 3,00134 2 /5X, 'MODULUS =',1PE12. 3)00135 WRITE(6,630) HT, WD, LNGTH, IX, AREA00136 630 FORMAT (/5X, 'GEOMETRY: ',00137 1 /5X, 'HEIGHT =',1PE12.3,

138 2 /5X, 'WIDTH =',1PE12.3,

00139 3 /5X, 'LENGTH =', 1PE12 . 3,00140 4 /5X, 'IXX =',1PE12.3,

00141 5 /5X, 'AREA =',1PE12.3)

00142 WRITE (6, 640) GAMMA, BETA, ERRCRT,MAXITR

00143 640 FORMAT (/5X, 'GUASS-SEIDEL: ',00144 1 /5X, 'GAMMA =',1PE12.3,

00145 1 /5X, 'BETA =',1PE12.3,

00146 1 / 5X, 'ERRCRT =',1PE12.3,

00147 2 /5X, 'MAXITR =', 15)

00148 WRITE(6,650) DT,TERM,H,NE

00149 650 FORMAT(/5X, 'OTHER INFORMATIONS: ',

00150 1 /5X, 'TIME INCREMENT =', 1PE12.3,

00151 1 /5X, 'TERMINATION T =', 1PE12.3,

00152 2 /5X, 'ELEMENT LENGTH =', 1PE12.3,

00153 3 //5X, 'NUMMER OF ELEMENTS =',I5)

00154 IF(IWRT.EQ.O) WRITE(6,654) NFRQ

00155 IF(IWRT.EQ.l) WRITE(6,656)

00156 654 FORMAT (//5X, 'FREQUENCY OF PRINT OUT IS ',14)

00157 656 FORMAT (//5X, 'JUST WRITE EVERY THING !')

00158 IF(KODBND.EQ.O) WRITE(6,660)

00159 IF(KODBND.EQ.l) WRITE(6,670)

00160 660 FORMAT (//5X, 'PRESCRIBED BOUNDARIES')

00161 670 FORMAT (//5X, 'VIBRATORY BOUNDARIES')

00162 IF(KODLIN.EQ.O) WRITE(6,674)

00163 IF(KODLIN.EQ.l) WRITE(6,676)

00164 674 FORMAT (//5X, "LINEAR PROBLEM')

00165 676 FORMAT (//5X, 'NONLINEAR PROBLEM')

00166 * IBD=BOUNDARY CODE (0 FIXED, 1 FREE)

00167 READ(5,*) (IBD(I) , I-l,NBOUND)

00168 WRITE(6,710) (IBD (I) , I=l,NBOUND)

00169 710 FORMAT (//2X, 'BOUNDARY CONDITIONS: ',/5X, "IBD (I) : '.413)

00170 READ(5,*) EQM1, EQC1, EQK1,EQMN,EQCN, EQKN

00171 WRITE(6,730) EQM1, EQC1, EQK1, EQMN, EQCN, EQKN

76

00172 730 FORMAT(//2X, 'EQUIVALENT MASS, DAMPING, STIFNESS: ',

00173 1 /5X, 'AT FIRST (LHS) END :'

, 1P3E12 . 3,00174 2 /5X, 'AT LAST (RHS) END:

'

,1P3E12 . 3)

00175 IF(KODINT.EQ.O) WRITE(6,678)

00176 IF(KODINT.EQ.l) WRITE(6,679)

00177 678 FORMAT (//5X, 'INITIAL DISPLACEMET AND VELOCITIES')

00178 679 FORMAT (//5X, 'INITIAL DISPLACEMENT AT THE FIRST TWO STEPS')

00179 * INITIAL CONDITIONS

00180 WRITE(6,680)

00181 680 FORMAT (///5X, 'INITIAL CONDITIONS',

00182 + /5X,'

')

00183 WRITE(6,690)

00184 690 FORMAT </5X, 'DISPLACEMENTS: ')

00185 READ(5,*) (Y0 (I) , 1=1, NN)

00186 WRITE(6,*) (Y0 (I) , 1=1, NN)

00187 IF(KODINT.EQ.O) THEN

00188 WRITE(6,700)

00189 700 FORMAT </5X, 'VELOCITIES: ')

00190 READ(5,*) (V0 (I) , 1=1, NN)

00191 WRITE<6,*) (V0 (I) ,I=1,NN)

00192 DO 20 1=1, NN

00193 20 Y1(I)=DT*V0 (I)+Y0 (I)

00194 END IF

00195 DO 25 1=1, NN

00196 Y(I)=Y1(I)

00197 25 ENDDO

00198 * WRITE THE FIRST TWO STEPS TO OUTPUT FILE

00199 WRITE (12,*) ZER0,Y1(1)

00200 WRITE (12,*) DT,Y1(1)

00201 WRITE(33,*) ZER0,Y1(33)

00202 WRITE(33,*) DT,Y1(33)

00203 WRITE (41,*) ZERO, YI (41)

00204 WRITE (41,*) DT,Y1(41)

00205 * FIXED MATRICES, [GM] AND [GK1]

00206 CALL ELEMENT(N,H,M,C,K1,K2,K3,EF)

00207 CALL GLOBFX (N, NE, NN, NB,M, Kl, EF, GM, GK1, GF)

00208 *. ...INSERT B.C. (KOD=l)

0020 9 * INITIAL FORCED B. C.

00210 L=NN-1

00211 K=NB-1

00212 IF (CONTROL . EQ . 3 .OR. CONTROL . EQ . 4) THEN

00213 READ(8,*) ( (FF(I, J), J=l, 4) , 1=1, 2)

00214 ELSE

00215 DO 1=1,2,1

00216 DO J=l, 4, 1

00217 FF(I,J)= 0.0

00218 ENDDO

00219 ENDDO

00220 ENDIF

00221 DO 101 1=1,2

00222 EN(I,1)=FF(I,1)+GF(1)

00223 EN(I,2)=FF(I,2)+GF(2)

00224 EN(I,L)=FF(I,3)+GF(L)

00225 EN(I,NN)=FF(I,4)+GF(NN)

00226 DO 102 J=3,NN-2

00227 EN(I,J)=GF(J)

00228 102 ENDDO

77

(RO(I) , 1=1, NN)

(Rl(I) ,I=1,NN)

(R(D , 1=1, NN)

00229 101 ENDDO

00230 * BOUNDARY CONDITIONS

00231 IF(KODBND.EQ.l) THEN

00232 GM(1,1)=GM(1,1)+EQM1

00233 GM(L,K)=GM(L,K)+EQMN

00234 END IF

00235 * TIME MARCHING

00236 DO 100 WHILE (T.LE.TERM)

00237 T=T+DT

00238 KOUNT=KOUNT+l

00239 IFRQ=IFRQ+1

00240 CALL GLOBVR (N, NE, NN, NB, LNGTH, C, K2, K3, GK1, GC, GK)

00241 * INSERT B.C. (KOD=l)

00242 IF (KODBND.EQ. 1) THEN

00243 GC(1,1)=GC(1,1)+EQC1

00244 GK(1, 1)=GK(1, D+EQK1

00245 GC(L,K)=GC(L,K)+EQCN

00246 GK(L,K)=GK(L,K) +EQKN

00247 END IF

00248 CALL NUMARK (N, NB,NN, GM, GC, GK, A, B, D)

00249 CALL MULT (NN, NB,NE,D, Y0, R0)

00250 CALL MULT(NN,NB,NE,B,Y1,R1)

00251 DO 30 1=1, NN

00252 30 R(I)=-(R1(I)+R0(I) )

00253 IF(IWRT.EQ.l) THEN

00254 WRITE(6,930)

00255 WRITE'6,940)

00256 WRITE(6,940)

00257 WRITE(6,940)

00258 END IF

00259 * INSERT B.C. (KOD=0)

00260 * FBD=FORCED BOUDARIES (Q0, -M0, -QN, MN)

00261 IF (CONTROL . EQ . 3 .OR. CONTROL .EQ. 4) THEN

00262 READ(8,*) (FF (3, I) , 1=1, NBOUND)

00263 ELSE

00264 DO 1=1, NBOUND, 1

00265 FF(3,I)= 0.0

00266 ENDDO

00267 ENDIF

00268 EN(3,1)=FF(3,1)+GF(1)

00269 EN(3,2)=FF(3,2)+GF(2)

00270 EN(3,L)=FF(3,3)+GF(L)

00271 EN(3,NN)=FF(3, 4)+GF(NN)

00272 DO 103 J=3,NN-2

00273 EN(3, J)=GF(J)

00274 103 ENDDO

00275 DO 35 1=1, 4

00276 35FBD(I)=-DT2*(BETA*EN(3,I)+A2*EN(2,I)+A1*EN(1,I) )

00277 DO 104 1=1, NN

00278 R(I)=R(D+FBD(I)

00279 104 ENDDO

00280 *

00281 R(L)=R(L)+FBD(3)

00282 R(NN)=R(NN)+FBD(4)

00283 N4=NN-N

00284 DO 60 1=1, NBOUND

00285 IF(IBDd) .EQ.0) THEN

78

00286 IF(I.LE.2) THEN

00287 DO 40 J=1,N

00288 A(I,J)=0.0

00289 A(J,I)=0.0

00290 40 END DO

00291 A(I,I)=1.0

00292 R(I)=0.0

00293 ELSE

00294 I2=N4+I

00295 IP2=I+2

00296 DO 50 J=1,N

00297 J2=N4+J

00298 JP2=J+2

00299 A(I2, JP2)=0.0

00300 A(J2,IP2)=0.0

00301 50 END DO

00302 A(I2, IP2)=1.0

00303 R(I2)=0.0

00304 END IF

00305 END IF

00306 60 END DO

00307 IF (IWRT.EQ. 1) THEN

00308 WRITE(6, 910)

00309 WRITE (6, 940) ( (A (I, J) , J=1,NB) ,I=1,NN)

00310 WRITE(6, 920)

00311 WRITE(6,940) (R(I) , 1=1, NN)

00312 910 FORMAT (/5X,'

[A]'

)

00313 920 FORMAT (/5X,'

R')

00314 930 FORMAT(/5X, 'R0,R1,R')

00315 940 FORMAT (5X, 1P6E12.3)

00316 END IF

00317 IF(KODLIN.EQ.O) CALL GUAS (NN, NB, NE, A, R, Y)

00318 IF (KODLIN.EQ. 1) CALL SEIDEL (NN, NB, NE, A, R, Y, Y0)

00319 IF (IFRQ.EQ.NFRQ.OR.NFRQ.EQ.l) THEN

00320 IFRQ=0

00321 CALL OUTPUT (NN, NE, T, Y, SIG)

00322 END IF

00323 DO 70 1=1, NN

00324 YO (I)=Y1(I)

00325 Y1(I)=Y(I)

00326 70 END DO

00327 DO 8 0 J=l, NBOUND

00328 EN(1, J)=EN(2, J)

00329 EN (2, J)=EN(3, J)

00330 80 END DO

00331 100 END DO

00332 WRITE(9,*) STOP, (ZER(I) ,1=1, NN)

00333 WRITE (10,*) STOP, (ZER(I) ,1=1, NN)

00334 STOP

00335 END

79

00001 *

00002 SUBROUTINE ELEMENT (N, H,M, C,K1, K2, K3, EF)

00003 *

00004 ******************************** ***

00005 *

00006 * THIS SUBROUTINE IS USED TO CALCULATE THE ELEMENT STIFFNESS

00007 *MATRIX, THE ELEMENT DAMPING MATRIX, AND THE ELEMENT MASS MATRIX.

00008

00009 ******************************* ****

00010 *

00011 REAL*4 M(N,N) ,C(N,N) ,K1(N,N) ,K2 (N,N) ,K3(N,N) ,EF(N)

00012 COMMON/MATDIM/RO,EE,AREA, IX, HT, P, G, P0,Vin

00013 COMMON/CONTR/NFRQ, IWRT, CONTROL

00014 H2=H*H

00015 H3=H*H2

00016 *MASS MATRIX [M]

00017 RA=RO*AREA

00018 M(l,l)=156.0

00019 M(1,2)=22.0*H

00020 M(l,3)=54.0

00021 M(1,4)=-13.0*H

00022 M(2,2)=4.0*H2

00023 M(2,3)=-M(l,4)

00024 M(2, 4)=-3.0*H2

00025 M(3,3)=M(1,1)

00026 M(3, 4)=-M(l,2)

00027 M(4,4)=M(2,2)

00028 DUM=H/420.0

00029 DO 10 1=1, N

00030 DO 10 J=1,I

00031 M(J,I)=DUM*M(J,I)

00032 M(I,J)=M(J,I)

00033 10 END DO

00034 * DAMPING MATRIX [C]

00035 C(l,l)=-0.5

00036 C(1,2)=0.1*H

00037 C(l,3)=0.5

00038 C(l,4)=-C(l,2)

00039 C(2,2)=0.0

00040 C(2,3)=C(1,2)

00041 C(2,4)=-H2/60.0

00042 C(3,3)=0.5

00043 C(3,4)=C(1,2)

00044 C(4,4)=0.0

00045 DO 20 1=2, N

00046 DO 20 J=1,I-1

00047 20 C(I,J)=-C(J,D

00048 * STIFNESS MATRICES [Ki] i=l,2,3.

00049 Kl(l,l)=12.0

00050 K1(1,2)=6.0*H

00051 Kl(l,3)=-12.0

00052 K1(1,4)=K1(1,2)

00053 K1(2,2)=4.0*H2

00054 K1(2,3)=-K1(1,2)

00055 K1(2,4)=2.0*H2

00056 K1(3,3)=K1(1,1)

00057 K1(3,4)=K1(2,3)

80

00058 K1(4,4)-K1(2,2)00059 *

00060 K3(l,l)6.0/(5.0*H)

00061 K3(l,2)=-l.l00062 K3(l,3)=-K3(l,l)00063 K3(l,4)0.100064 K3(2,2)=-2.0*H/15.000065 K3(2,3)=0.100066 K3(2,4)=H/30.000067 K3(3,3)=K3(1,1)00068 K3(3,4)=l.l00069 K3(4,4)=K3(2,2)00070 *

00071 DO 30 I-1,N

00072 DO 30 J-1,100073 K1(J,I)=K1(J, I)/H300074 K1(I, J)-K1(J, I)00075 K2(J, I)-C(J,I)00076 K2(I,J)-C(I, J)00077 K3(I, J)-K3(J,I)00078 30 END DO

00079 K3(2,l)=-0.1

00080 K3(4,3)=0.1

00081 * ELEMENT FORCE MATRIX

00082 Fa=RA*G*H/2

00083 EF(l)=Fa

00084 EF(2)=Fa*H/6

00085 EF(3)=EF(1)00086 EF(4)EF(2)00087 * WRITE [M],[C],[Ki]00088 IF(IWRT.EQ.l) THEN

00089 WRITE (6, 610)00090 WRITE(6,640) ( (M (I, J) , J-l, 4) , 1=1, 4)00091 WRITE (6, 620)00092 WRITE(6,640) ( (C (I, J) , J-l, 4) , 1=1, 4)00093 WRITE (6, 630)00094 WRITE(6,640) ( (Kl (I, J) , J-l, 4) , 1-1, 4)00095 WRITE (6, 640) ( (K2 (I, J) , J=l, 4) , 1-1, 4)00096 WRITE(6,640) ( (K3 (I, J) , J-l, 4) , 1-1, 4)00097 610 FORMAT <//5X, 'ELEMENT MASS MATRIX [M] :

'

)00098 620 FORMAT (//5X, 'ELEMENT DAMP MATRIX [C] :

'

)00099 630 FORMAT (//5X, 'ELEMENT STIF MATRIX [K] :

'

)00100 640 FORMAT (2X,1P4E13. 4)

00101 END IF

00102 RETURN

00103 END

81

00001 *

00002 SUBROUTINE GLOBFX (N, NE, NN, NB,M, Kl, EF, GM, GK1, GF)

00003 *

00004 ***********************************

00005 *

00006 *THIS SUBROUTINE IS USED TO ASSEMBLE THE GLOBAL MATRICES BASED

00007 *ON THE ELEMENT MATRICES FROM THE PREVIOUS SUBROUTINE.

00008 *

00009***********************************

00010 *

00011 COMMON/CONTR/NFRQ, IWRT

00012 REAL*4 M(N,N) ,K1(N,N) , IX,EF(N)

00013 REAL*4 GM (NN, NB) ,GK1 (NN, NB) , GF (NN)

00014 DIMENSION Bl (2, 6) ,B2 (2,6)

00015 COMMON/MATDIM/RO,EE,AREA, IX, HT, P,G, P0,Vin

00016 * INITIALIZATIO

00017 DO 5 1=1,2

00018 DO 5 J=l,6

00019 B1(I,J)=0.0

00020 B2(I,J)=0.0

00021 5 END DO

00022 * PRELIMINARIES

00023 RA=RO*AREA

00024 FX=EE*IX

00025 DO 10 1=1, N

00026 DO 10 J=1,N

00027 M(I, J)=RA*M(I, J)

00028 Kl (I, J)=FX*K1 (I, J)

00029 10 END DO

00030 * FIRST AND LAST PAIRS

00031 DO 20 1=1,2

00032 K=NN-2+I

00033 IP2=I+2

00034 DO 20 J=1,N

00035 JP2=J+2

00036 GM(I,J)=M(I,J)

00037 GK1(I,J)=K1(I, J)

00038 GM(K,JP2)=M(IP2,J)

00039 GK1(K, JP2)=K1(IP2, J)

00040 20 END DO

00041 * BASIC UNIT

00042 DO 30 1=1,2

00043 IP2=I+2

00044 DO 30 J=1,NB

00045 JM2=J-2

00046 IF(J.LE.4) THEN

00047 B1(I,J)=M(IP2,J)

00048 B2(I,J)=K1(IP2,J)

00049 END IF

00050 IF(J.GT.2) THEN

00051B1(I,J)=B1(I,J)+M(I,JM2)

00052B2(I,J)=B2(I,J)+K1(I,JM2)

00053 END IF

00054 30 END D

00055 * REPEAT BASIC UNIT

00056 NEM1=NE-1

00057 DO 40 I=1,NEM1

82

00058 DO 40 K=l,2

00059 L=2*I+K

00060 DO 40 J=1,NB

00061 GM(L, J)=B1(K, J)00062 GK1(L, J)=B2(K, J)

00063 40 END DO

00064 * GLOBAL FOR MATRIX

00065 GF(1)=EF(1)

00066 GF(2)=EF(2)00067 GF(NN-1)=EF(3)00068 GF(NN) = EF(4)

00069 DO 50 I=3,NN-3,2

00070 GF(I) = EF(3)+EF(1)

00071 GF(I+1) = EF(4)+EF(2)

00072 50 ENDDO

00073 *

00074 *PRINT OUT

00075 IF(IWRT.EQ.l) THEN

00076 WRITE(6, 610)

00077 WRITE (6, 630) ( (GM(I, J) , J=1,NB) , 1=1, NN)

00078 WRITE(6, 620)

00079 WRITE (6, 630) ( (GK1 (I, J) , J=1,NB) , 1=1, NN)

00080 610 FORMAT (//5X, 'GLOBAL MASS MATRIX [GM]'

)

00081 620 FORMAT (//5X, 'GLOBAL STIF MATRIX [GK1]')

00082 630 FORMAT (2X, 1P6E12 .3)

00083 END IF

00084 RETURN

00085 END

83

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SUBROUTINE GLOBVR(N,NE,NN,NB, X, C,K2,K3, GK1, GC, GK)* *

* *

**********************************

THIS PROGRAM IS USED TO ASSEMBLE THE VARIABLE GLOBAL

MATRICES BASED ON THE ELEMENT MATRICES FROM SUBROUTINE

'ELEMENT'.

**********************************

* *

* *

REALM C(N,N) ,K2(N,N) ,K3(N,N)REALM GK1 (NN,NB) ,GC(NN,NB) ,GK(NN,NB)

REALM LMD(2000) ,V(2000) ,VD(2000) ,Q(2000) ,TAU(2000)

COMMON/MATDIM/RO, EE,AREA, IX, HT, P , G, P0 ,Vin

COMMON/DELTAS /DT , H

COMMON/CONTR/NFRQ, IWRT, CONTROL* INITIALIZATION

DO 5 1=1, NN

DO 5 J=1,NB

GC(I, J) =0.0

GK(I, J) =0.0

5 END DO

* PREREQUISITES

IF (CONTROL .EQ. 4) THEN

READ(7,*) V1,V2,V1D,V2D,P,PD

SLOPV=(V2-Vl) /X

SLOPD- (V2D-V1D) /X

DV-H*SLOPV

DD=H*SLOPD

V(l)-Vl+DV/2.0

VD(l)-VlD+DD/2.0

DO 10 1-2, NE

V(I)-V(I-1)+DV

VD(I)=VD(I-1)+DD

10 END DO

ELSE

DO I-1,NE

V(I)=Vin

ENDDO

P - P0

EPSD =0.0

ENDIF

* COMPUTE TAU,Q,LMD PER ELEMENT

RA=RO*AREA

FX=EE*IX

EPSD-PD/ (EE*AREA)

DO 20 1=1, NE

Q(I)-RA*V(I)

QDI-RA*VD(I)

TAU(I)=Q(D*V(D-P

LMD (I) -QDI+Q (I) *EPSD

20 END DO

*. ..FIRST

PAIRS OF ROWS

DO 30 1-1,2

84

00058 DO 30 J=1,N

00059 GC(I,J)=2.0*Q(1)*C(I,J)00060 GK(I,J)=LMD(1)*K2(I,J)+TAU(1)*K3(I,J)00061 30 END DO

00062 * LAST PAIRS OF RAWS

00063 DO 40 1=1,2

00064 K=NN-2+I

00065 IP2=I+2

00066 DO 40 J=1,N

000 67 JP2=J+2

000 68 GC(K,JP2)=2.0*Q(NE)*C(IP2, J)000 6 9 GK(K, JP2)=LMD(NE)*K2(IP2, J)+TAU(NE) *K3(IP2, J)00070 40 END DO

00071 *IN BETWEEN

00072 NEM1=NE-1

00073 DO 50 I=1,NEM1

00074 IP1=I+1

00075 DO 50 K=l,2

00076 L=2*I+K

00077 KP2=K+2

00078 DO 50 J=1,NB

00079 JM2=J-2

00080 IF(J.LE.4) THEN

00081 GC(L, J)=2.0*Q(I) *C(KP2, J)

000 82 GK(L, J)=LMD(I) *K2 (KP2 , J) +TAU (I) *K3 (KP2, J)

00083 END IF

00084 IF(J.GT.2) THEN

000 85 GC(L, J)=GC(L, J) +2.0*Q(IP1) *C(K, JM2 )

0008 6 GK(L, J)=GK(L, J) +LMD(IP1) *K2 (K, JM2) -t-TAU(IPl) *K3(K, JM2)

00087 END IF

00088 50 END DO

00089 DO 60 1=1, NN

00090 DO 60 J=1,NB

00091 60 GK(I, J)=GK(I, J)+GK1(I, J)

00092 * WRITE

00093 IF(IWRT.EQ.l) THEN

00094 WRITE(6,610)

00095 WRITE(6,630) ( (GC ( I, J) , J=l, NB) , 1=1, NN)

00096 WRITE(6,620)

00097 WRITE(6,630) ( (GK ( I, J) , J=l, NB) , 1=1, NN)

00098 610 FORMAT (//5X, 'GLOBAL DAMPING MATRIX [GC]')

00099 620 FORMAT (//5X, 'GLOBAL STIFNESS MATRIX [GK]'

)

00100 630 F0RMAT(2X,1P6E12.3)

00101 END IF

00102 RETURN

00103 END

85

00001 *

00002 SUBROUTINE NUMARK (N,NB,NN,GM, GC, GK, A, B, D)

00003 *

00004 **********************************

00005 *

00006 * THIS SUBROUTINE IS USED TO TRANSFORM A SYSTEM OF DIFFERENTIAL

00007 * EQUATIONS INTO A SYSTEM OF LINEAR ALGEBRA EQUATIONS.

00008 *

00009 **********************************

00010 *

00011 REAL*4 A(NN,NB) ,B(NN,NB) ,D(NN,NB)

00012 REAL*4 GM (NN, NB) , GC (NN, NB) , GK (NN, NB)

00013 COMMON/NEWMRK/BETA, GAMMA

00014 COMMON/DELTAS /DT,H

00015 COMMON/CONTR/NFRQ, IWRT, CONTROL

00016 *PREREQUISITES

00017 D2=DT*DT

00018 Dll=1.0

00019 D12=DT*GAMMA

00020 D13=D2*BETA

00021 D21=-2.0

00022 D22=DT*(1.0-2.0*GAMMA)

00023 D23=D2* (0 . 5-2 . 0*BETA+GAMMA)

00024 D31=1.0

00025 D32=DT* (-1.0+GAMMA)

00026 D33=D2* (0 . 5+BETA-GAMMA)

00027 *....COMPUTE [A] , [B] , [C]

00028 DO 10 1=1, NN

00029 DO 10 J=1,NB

00030 A (I, J)=D11*GM(I, J) +D12*GC(I, J)+D13*GK(I, J)

00031 B(I, J)=D21*GM(I, J) +D22*GC (I, J)+D23*GK(I, J)

00032 D(I, J)=D31*GM(I, J)+D32*GC(I, J) +D33*GK (I, J)

00033 10 END DO

00034 * WRITE [A],[B],[D]

00035 IF(IWRT.EQ.l) THEN

00036 WRITE(6,610)

00037 WRITE(6,640) ( (A(I, J) , J=1,NB) , 1=1, NN)

00038 WRITE(6,620)

00039 WRITE(6,640) ( (B (I, J) , J=l, NB) , 1=1, NN)

00040 WRITE(6,630)

00041 WRITE(6,640) ( (D (I, J) , J=l, NB) , 1=1, NN)

00042 610 FORMAT(/5X,'[A]')

00043 620 FORMAK/5X,'

[B]'

)

00044 630 FORMAK/5X,'

[D]'

)

00045 640 FORMAT(5X, 1P6E12.3)

00046 END IF

00047 RETURN

00048 END

86

00001 *

00002 SUBROUTINE MULT (N,M,NE, A, X, Y)

00003 REALM A(N,M) ,X(N) ,Y(N)

00004* FIRST PAIR

00005 DO 20 K=l,2

00006 SUM=0 . 0

00007 DO 10 J=1,M

00008 10 SUM=SUM+A(K, J) *X(J)

00009 Y(K)=SUM

00010 20 END DO

00011 * LAST PAIR

00012 NM2=N-2

00013 NMM=N-M

00014 DO 40 K=l,2

00015 SUM=0 . 0

00016 I=NM2+K

00017 DO 30 J=1,M

00018 30 SUM=SUM+A ( I , J) *X(NMM+J)

00019 Y(I)=SUM

00020 40 END DO

00021* IN-BETWEEN PAIRS

00022 DO 100 11=2, NE

00023 I0=2*(II-1)

00024L0=2* (II-2)

00025 DO 60 K=l,2

00026 SUM=0 . 0

00027 I=I0+K

00028 DO 50 J=1,M

00029 L=L0+J

00030 SUM=SUM+A(I, J) *X(L)

00031 50 END DO

00032 Y(I)=SUM

00033 60 END DO

00034 100 END DO

00035 RETURN

00036 END

87

00001 *

00002 SUBROUTINE SEIDEL (N,M,NE,A,R, X, XO)

00003 *

00004 ************************** *******

00005 *

00006 * THIS SUBROUTINE IS USED TO SOLVE A SYSTEMOF LINEAR ALGEBRAIC

00007 * EQUATIONS USING GAUSS-SEIDEL METHOD.

00008 *

00009 ******************* **************

00010 *

00011 DIMENSION A(N,M) ,R(N) ,X(N) , X0 (N)

00012 COMMON/SEIDEL/ERRCRT,MAXITR

00013 COMMON /CONTR/NFRQ, IWRT, CONTROL

00014 KOUNT=l

00015 *ITERATION

00016 100 CONTINUE

00017 DO 10 1=1, N

00018 10 X0(I)=X(I)

00019 *... .FIRST PAIR

00020 DUM=A(1,1)

00021 SUM=0.0

00022 DO 20 J=2,M

00023 20 SUM=SUM+A(1, J) *X(J)

00024 X(1)=(R(1) -SUM) /DUM

00025 DUM=A(2,2)

00026 SUM=A(2,1)*X(1)

00027 DO 30 J=3,M

00028 30 SUM=SUM+A(2, J) *X(J)

00029 X(2)=(R(2)-SUM) /DUM

00030 * IN-BETWEEN

00031 DO 60 11=2, NE

00032 I0=2*(II-1)

00033 L0=2*(II-2)

00034 DO 50 K=l,2

00035 SUM=0.0

00036 I=I0+K

00037 IF(K.EQ.l) IPIV=3

00038 IF(K.EQ.2) IPIV=4

00039 DUM=A(I,IPIV)

00040 SUM=0.0

00041 DO 40 J=1,M

00042 IF(J.EQ.IPIV) GO TO 40

00043 L=L0+J

00044 SUM=SUM+A(I, J) *X(L)

00045 40 END DO

00046 X(I)= (R(U-SUM)/DUM

00047 50 END DO

00048 60 END DO

000 4 9 * LAST PAIRS

00050 NM1=N-1

00051 NM2=N-2

00052 NM7=N-M

00053 MM1=M-1

00054 MM2=M-2

00055 DUM=A(NM1,MM1)

00056 SUM=0.0

00057 DO 70 J=1,M

88

00058 IF(J.EQ.MMl) GO TO 70

00059 L=NM7+J

00060 SUM=SUM+A(NM1, J) *X(L)00061 70 END DO

00062 X(NM1)=(R(NM1)-SUM)/DUM

00063 DUM=A(N,M)

00064 SUM=0.0

00065 DO 80 J=1,MM1

00066 L=NM7+J

00067 SUM=SUM+A(N, J) *X(L)00068 80 END DO

00069 X(N)=(R(N)-SUM) /DUM

00070 * CHECK CONVERGENCE

00071 ERRMAX=0.0

00072 DO 90 1=1, N

00073 ERRI=X(I) -X0 (I)

00074 ABSERR=ABS (ERRI)

00075 ERRMAX=AMAX1 (ABSERR, ERRMAX)

00076 90 END DO

00077 IF ( ERRMAX. LE. ERRCRT) KOUNT=0

00078 IF ( ERRMAX. GT. ERRCRT) THEN

00079 KOUNT=KOUNT+l

00080 IF (KOUNT.GT.MAXITR) THEN

00081 KOUNT=0

00082 WRITE(6, 610)

00083 610 FORMAT (//5X,' **** NO CONVERGENCE ****';

0008 4 END IF

00085 END IF

00086 IF(IWRT.EQ.l) THEN

00087 WRITE(6,620) KOUNT

00088 620 FORMAT (/2X, 'ITERATION NO. :', 14)

00089 WRITE(6,630) (X(I),I=1,N)

00090 630 FORMAT (2X,1P10E11. 3)

00091 WRITE(6,640) ERRMAX

00092 640 FORMAT ( 2X,' ERROR= '

,1PE12 . 3)

00093 END IF

00094 IF(KOUNT.NE.O) GO TO 100

000 95 RETURN

00096 END

89

00001 *

00002 SUBROUTINE GUAS (N,M,NE, A, R, Y)

00003 *

00004 a**********************************,

00005 *

00006 * THIS SUBROUTINE IS USED TO SOLVE A SYSTEM OF LINEAR ALGEBAIC

00007 * EQUATIONS USING GAUSS-ELEMINATION METHOD WITH BACK SUBSTITUTION.

00008 *

00009************************************

00010 *

00011 DIMENSION A(N,M) ,R(N) ,Y(N)

00012 * PRELIMINARIES

00013 NM1=N-1

00014 MM1=M-1

00015 MM2=M-2

00016 * ELEMINATION

00017 * FIRST PAIR

00018 DO 10 K=l,2

00019 KP1=K+1

00020 DO 10 I=KP1,MM2

00021 C=A(I,K)/A(K,K)

00022 DO 5 J=KP1,M

00023 5 A(I, J)=A(I, J)-C*A(K, J)

00024 R(I)=R(I)-C*R(K)

00025 10 END DO

00026 * IN-BETWEEN

00027 DO 50 11=2, NE-1

00028 10=2* (II-l)

00029 DO 50 K=l,2

00030 KP1=K+1

00031 IPV=I0+K

00032 JPV=2+K

00033 IF(K.EQ.l) THEN

00034 IPVP1=IPV+1

00035 JPVP1=JPV+1

00036 C=A(IPVP1,JPV)/A(IPV, JPV)

00 037 DO 20 J=JPVP1,M

00038 20 A(IPVP1, J)=A(IPVP1, J)-C*A(IPV,J)

00039 R(IPVP1)=R(IPVP1)-C*R(IPV)

000 40 END IF

00041 DO 40 IP=1,2

00042 I=(l0+2)+IP

00043 C=A(I,K)/A(IPV,JPV)

00044 DO 30 J=KP1,MM2

00045 JJ=JPV+J-K

00046 30 A(I,J)=A(I,J)-C*A(IPV,JJ)

00047 R(I)=R(I)-C*R(IPV)

00048 40 END DO

00049 50 END DO

00050 * LAST PAIR

0005110=2* (NE-1)

00052 DO 70 K=l,3

00053 IPV=I0+K

00054 JPV=2+K

00055 IPVP1=IPV+1

00056 JPVP1=JPV+1

00057 DO 70 I=IPVP1,N

90

00058 C=A(I, JPV)/A(IPV,JPV)

00059 DO 60 J=JPVP1,M

00060 60 A(I, J)=A(I, J)-C*A(IPV, J)

00061 R(I)=R(I)-C*R(IPV)

000 62 7 0 END DO

00063 * BACK SUBSTITUTION

00064 * FIRST PAIR

00065 R(N)=R(N)/A(N,M)

00066 R(NM1)=(R(NM1) -A(NM1,M) *R(N) ) /A(NM1,MM1)

00067 * IN-BETWEEN

00068 DO 90 11=1, NE-1

00069 IB=2*(NE-II)

00070 DO 90 K=l,2

00071 KB=3-K

00072 I=IB+KB

00073 IF(K.EQ.l) IPV=4

00074 IF(K.EQ.2) IPV=3

00075 SUM=0.0

00076 IPVP1=IPV+1

00077 DO 80 J=IPVP1,M

00078 L=I+J-IPV

00079 80 SUM=SUM+A(I, J) *R(L)

00080 R(I)=(R(I)-SUM) /A(I,IPV)

00081 90 END DO

00082 * FIRST PAIR

00083 DO 100 K=l,2

00084 KB=3-K

00085 SUM=0.0

00086 DO 95 J=KB+1,4

00087 95 SUM=SUM+A(KB, J) *R(J)

00088 R (KB) =(R (KB) -SUM) /A (KB, KB)

00089 100 END DO

00090 * OK NOW TO Y

00091 DO 110 1=1, N

00092 110 Y(I)=R(D

00093 RETURN

00094 END

91

00001

00002

00003

00004

00005

00006

00007

00008

00009

00010

00011

00012

00013

00014

00015

00016

00017

00018

00019

00020

00021

00022

00023

00024

00025

00026

00027

00028

00029

00030

00031

00032

00033

00034

00035

00036

00037

00038

00039

00040

00041

00042

00043

00044

00045

00046

SUBROUTINE OUTPUT (N,NE, T, Y, SIG)

** **************************** ******

THIS SUBROUTINE IS USED TO WRITE THE OUTPUT RESULTS FOR PLOTTING.

************************

COMMON /MATDIM/RO, EE, AREA, IX, HT, P, G, P0 ,Vin

COMMON/DELTAS/DT,H

REAL*4 Y(N) , SIG(NE)

REAL LEN

WRITE(6,610) T

610 FORMAT (//5X,'TIME='

, 1PE12 . 3, /5X,'

WRITE(6,620) (Y(I) ,I=1,N-1,2)

620 FORMAT (2X,'DISP'

, 1P10E11. 3)

WRITE(6,640) (Y(I) , 1=2, N, 2)

640 FORMAT (2X, 'SLOP', 1P10E11. 3)* FOR POST PROCESSOR

IF (T .GT. 0.301 .AND. T . LT . 0.302) THEN

WRITE(6,*) T

DO 77 1=1, N, 2

LEN = H*( (1-1) /2)

WRITE(97,*) LEN, Y(I)

77 CONTINUE

ENDIF

IF (T .GT. 1.201 .AND. T . LT . 1.202) THEN

WRITE (6,*) T

DO 78 1=1, N, 2

LEN = H*( (1-1) /2)

WRITE(98,*) LEN, Y(I)

7 8 CONTINUE

ENDIF

IF (T .GT. 1.801 .AND. T . LT . 1.802) THEN

WRITE(6,*) T

DO 79 1=1, N, 2

LEN = H*((I-l)/2)

WRITE(99,*) LEN, Y(I)

***** ******

',/2X>

7 9 CONTINUE

ENDIF

WRITEU2,*) T,Y(1)

WRITE(33,*) T,Y(33)

WRITE(41,*) T,Y(41)

RETURN

END

92

PROGRAM AXIAL

93

00001 *

00002 * This program is used to provide the program WEB1 with

00003 * those variables in the axial motion and the boundary00004 *

conditions at the two end3 for the vibration analyses

00005 *of phase shift and transient effects.

00006 *

00007 * Variable desciption:

00008 * J1,J2 polar moment of inertia of rollers

00009 * B1,B2 viscous damping of rollers 1 & 2

00010 *HD1,HD2 radii of rollers 1 & 2

00011 *TF frictional torque of driven roller

00012 * K axial stiffness of web

00013 *UNBL1,UNBL2 unbalanced forces of roller 1 & 2

00014 *TRQ0 initial applied torque

00015 * TRQ1 final torque applied (for transient analysis only)

00016 *OMG01,OMG02 initial angular velocities of rollers 1 & 2

00017 *P0 initial tension in the web

00018 * TEND end time

00019 * DT time increment

00020 * T0,T1 start & end time of changing torque

00021 * TSLP time rate of changing torque

00022 *VI, V2 web velocities at the contact point with roller 1 &

00023 * V1D,V2D time rate of web velocities at the contact point

00024 *with rollers 1 & 2

00025 * P web tension

0002 6 * PRAT time rate of web tension

00027 * Q1,Q2 shear forces at the left and right ends

00028 * M1,M2 moments at the left and right ends

00029 *

00030 C

00031 C V1,V2,V1D,V2D,P,PRAT FILE 7

00032 C Q1,M1,Q2,M2 FILE 8

00033 C

00034 INTEGER TRANS

00035 PARAMETER NMX=2000

00036 PARAMETER NEQ=3

00037 DIMENSION XX (NEQ) ,F (NEQ)

00038 DIMENSION Rl (NEQ) , R2 (NEQ) , R3 (NEQ) , R4 (NEQ)

00039 REAL*4 J1,J2,K

000 40 COMMON/PARAM/J1, J2, Bl, B2, HD1, HD2

00041 COMMON/OTHER/TF,K,UNBLl,UNBL2

00042 COMMON/INPUT/TRQ0,TRQl,TSLP,T0,Tl

00043 C READ/WRITE DATA

00044 READ (5,*) TRANS ! This is a control number for

00045 C transient analysis.

00046 READ (5,*) Jl, J2, Bl, B2, HD1, HD2

00047 READ (5,*) TF, K, UNBL1,UNBL2

00048 READ (5,*) OMG01,OMG02,P0

00049 READ (5,*) TEND,DT

00050 READ (5,*) TRQ0 , TRQ1, TO, Tl

00051 WRITE(6,600)

00052 600 FORMAT (//2X,'INPUT DATA:

'

)

00053 WRITE(6,610) Jl, J2, Bl, B2, HD1, HD2

00054 610 FORMAT(/2X, 'SYSTEM PARAMETERS:',

00055 1 /2X, 'Jl=', 1PE12.3,'

(KG-M**2)',

00056 2 /2X, 'J2=', 1PE12.3,'(KG-M**2)',

00057 3 /2X, 'Bl=', 1PE12.3,'

(N-S-M)'

,

94

00058 4 /2X, 'B2=\ 1PE12.3,'

(N-S-M)',

00059 5 /2X, 'Rl=', 1PE12.3,'

(M)'

,

00060 6 /2X, 'R2=', 1PE12.3,'

(M)'

)

00061 WRITE(6,620) TF, K,UNBL1,UNBL2

00062 620 FORMAT (/2X, 'OTHER INFORMATIONS: ',

00063 1 /2X, 'FRICTIONAL TORQUE= '

, 1PE12 . 3,'

(N-M)'

,

00064 2 /2X, 'WEB AXIAL STIF K =',1PE12.3,*(N/M)',

00065 3 / 2X, 'UNBALANCE INROLl='

, 1PE12 . 3,'

(KG-M)',

00066 4 / 2X, 'UNBALANCE INROL2='

, 1PE12 . 3,'

(KG-M)')

00067 WRITE(6,630) OMG01, OMG02, P0

00068 630 FORMAT (/2X, 'INITIAL CONDITIONS: ',

00069 1 /2X, 'OMEGAl=',lPE12.3,'

(RAD/S)',

00070 2 /2X, 0MEGA2=',1PE12.3,'

(RAD/S)1,

00071 3 /2X, 'P(TEN)=',1PE12.3,'

(N)'

)

00072 WRITE(6,640) TEND,DT

00073 640 FORMAT (/2X, 'TEND, DT. ...', 1P2E12. 3)

00074 TSLP=(TRQ1-TRQ0) / (T1-T0)

00075 WRITE(6,650) TRQ0, TRQ1, TO, Tl, TSLP

00076 650 FORMAT (/ 2X, 'TRQ0=', 1PE12. 3,'

(NM)'

,

00077 1 /2X,'TRQ1='

00078 2 /2X,'TIM0='

00079 3 /2X,'TIM1='

00080 4 /2X,'TSLP='

00081 C INITIALIZATION

00082 WRITE(6,660)

00083 660 FORMAT (//10X, 'TIME', 5X, 'OMEGAl',6X, 'OMEGA2'

, 10X, 'P',

00084 *10X, 'Q1',10X, 'Q2')

00085 XX(1)=OMG01

00086 XX(2)=OMG02

00087 XX(3)=P0

00088 T=0.0

00089 CALL FUN (T, NEQ, XX, F)

00090 CALL OUTPUT (T, NEQ, XX, F)

00091 C NUMERICAL INTEGRATION

00092 DO 20 WHILE (T.LE.TEND)

00093 CALL RK4(T,DT,NEQ,XX,R1,R2,R3,R4,F)

00094 CALL OUTPUT (T, NEQ, XX, F)

00095 20 END DO

000 96 STOP

00097 END

1PE12,.3,'

(NM) ',

1PE12..3,

'

(SEC) ',

1PE12 3,'

(SEC) ',

1PE123,'

(NM/S) ')

95

00001 *

00002 * The fourth-order Runge-Kutta method

00003 *

00004 SUBROUTINE RK4 (T, DT, N, XX, Rl, R2, R3, R4, F)

00005 DIMENSION XX (N) , F (N) , Rl (N) , R2 (N) , R3 (N) , R4 (N)

00006 DIMENSION DUM(10)

00007 DO 10 1=1, N

00008 DUM(I)=XX(I)

00009 10 END DO

00010 CALL FUN(T,N,XX,F)

00011 DO 20 1=1, N

00012 Rl (I)=DT*F(I)

00013 XX(I)=DUM(I)+R1 (I) /2.0

00014 20 END DO

00015 T=T+DT/2.0

00016 CALL FUN(T,N,XX,F)

00017 DO 30 1=1, N

00018 R2 (I)=DT*F(I)

00019 XX(I)=DUM(I)+R2 (I) /2.0

00020 30 END DO

00021 CALL FUN(T,N,XX,F)

00022 DO 40 1=1, N

00023 R3(I)=DT*F(I)

00024 XX(I)=DUM(I)+R3(I)

00025 40 END DO

00026 T=T+DT/2.0

00027 CALL FUN (T, N, XX, F)

00028 DO 50 1=1, N

00029 R4 (I)=DT*F(I)

00030xX(I)=DUM(I)+(Rl(I)+2.0*R2(I)+2.0*R3(I)+R4(I))/6.0

00031 50 END DO

00032 RETURN

00033 END

96

00001 c

00002 SUBROUTINE FUN(T,N,X,F)

00003 DIMENSION X(N) ,F(N)

00004 REALM J1,J2,K

0000 5 COMMON/PARAM/J1, J2, Bl, B2, HD1, HD2

00006 COMMON/OTHER/TF,K,UNBLl,UNBL2

00 007 COMMON/INPUT/TRQ0,TRQl,TSLP,T0,Tl

00008 CALL INPUT (T,TRQ)

00009 F(l) =(TRQ-B1*X(1)-HD1*X(3) ) /Jl

00010 F(2) =(HD2*X(3)-B2*X(2)-TF) /J2

00011 F(3)=K* (HD1*X(1) -HD2*X(2) )

00012 RETURN

00013 END

00001 C

00002 SUBROUTINE INPUT (T,Y)

00003 COMMON/INPUT/TRQ0,TRQl,TSLP,T0,Tl

00004 IF(T.LE.TO) THEN

00005 Y=TRQ0

00006 ELSE IF(T.GT.TO.AND.T.LT.Tl) THEN

00007Y=TRQ0+TSLP* (T-T0)

00008 ELSE IF(T.GE.Tl) THEN

00009 Y=TRQ1

00010 END IF

00011 RETURN

00012 END

97

00001 C

00002 SUBROUTINE OUTPUT (T, N, X, F)

00003 DIMENSION X(N) , F (N)

00004 REALM J1,J2,K

00005 COMMON/PARAM/Jl , J2 , Bl , B2 , HD1 , HD2

00006 COMMON/OTHER/TF, K, UNBL1 , UNBL2

00007 C. . . . HISTORIES OF OMGl,OMG2,P TO FILES

00008 OMGl=X(l)

00009 OMG2=X(2)

00010 P =X(3)

00011 ALF1=F(1)

00012 ALF2=F (2)

00013 PRAT=F(3)

00014 IF (TRANS .EQ. 1) THEN

00015 WRITE (56,*) T,OMGl

00016 WRITE (55,*) T,OMG2

00017 WRITE(24,*) T,P

00018 ENDIF

00019 c. . , , OTHERS FOR WEB1

00020 c V1,V2,V1D,V2D,P,PD TO FILE 7

00021 VI =HDl*OMGl

00022 V2 =HD2*OMG2

00023 V1D=HD1*ALF1

00024 V2D=HD2*ALF2

00025 WRITE(7,610) V1,V2,V1D,V2D,P,PRAT

00026 c Q1,M1,Q2,M2 TO FILE 8

00027 OTl=OMGl*T

00028 OT2=OMG2*T

00029 SI =SIN(OTl)

00030 S2 =SIN(OT2)

00031 CI =COS(OTl)

00032 C2 =COS (OT2)

00033 Ql=+UNBLl* (0MG1*0MG1*S1-ALF1*C1)

00034 Q2=+UNBL2* (0MG2*0MG2*S2-ALF2*C2)

00035 ZER=0.0E0

00036 WRITE (8,*) Q1,ZER,Q2,ZER

00037 610 FORMAT (4X, 1P6E12 .3)

00038 C. ..LAST

INFORMATION

00039 IF (TRANS .EQ. 1) THEN

00040 CALL INPUT (T,TRQ)

00041 WRITE (27,*) T,TRQ

00042 ENDIF

00043 RETURN

00044 END

56,55,24

98

PROGRAM CONVER

99

00001 *

00002 * This program is used to convert the dita of the responses

00003 *of the web-roller system from the time domain into the

00004 *frequency domain.

00005 *

00006 * Variables Description:

00007 *

00008 * N number of data point

00009 * IN file control number

00010 * DT time increment

00011 *T(I) tmie array

00012 *SEQ(I) displacement array

00013 *FREQ(I) frequency array

00014 * COEF(I) amplitude in the frequency domain

00015 *

00016 *

00017 INTEGER N, I, IN

00018 REAL PI,DFREQ,DT, TN

00019 PARAMETER (N=1930, PI=3. 14159)

00020 REAL COEF(N) , SEQ(N) ,FREQ(N) ,T(N) ,seql(N)

00021 EXTERNAL FFTRF

00022 C

00023 READ (5,*) IN !Get control number

00024 IF (IN .EQ. 0) THEN

00025 C

0002 6 C reading input file by unit number

00027 C file unit 12 is the first node data (X/1 = 0.0)

00028 C file unit 33 is the node 33 data (X/1 =0.8)

00029 C file unit 41 is the node 41 data (X/1 =1.0)

00030 C

00031 DO 10 1=1, N

00032 READU2,*) T(I),SEQ(I)

00033 10 CONTINUE

00034 ELSE IF (IN . EQ . 1) THEN

00035 DO 11 1=1, N

00036 READ(33,*) T(I),SEQ(I)

00037 11 CONTINUE

00038 ELSE IF (IN .EQ. 2) THEN

00039 DO 12 1=1, N

00040 READ (41,*) T(I),SEQ(I)

00041 12 CONTINUE

00042 ENDIF

00043 DFREQ= 1/(2*T(N))

00044 C Compute the Fourier transform of SEQ

000 45 CALL FFTRF (N, SEQ, COEF)

00046 DO 30 1=1, N

00047 COEF (I) = ABS(COEFd) )

00 0 48 30 CONTINUE

00049 WRITE (98,*) FREQ(l), COEF(l)

00050 DO 40 1=2, N

00051 FREQ(I) = FREQd-D + DFREQ

00052 IF (FREQ(I) . LT . 220) THEN

00053 WRITE (98,*) FREQ(I), COEF (I)

00054 ENDIF

00055 40 CONTINUE

00056 STOP

00057 END

100