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Number

Mitigatingthe

Drag

Problem

Thesupercriticalairfoil

Sweep

TheArea

Rule

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NACA0012AT8DEGREES

-10

M

-

-8

-7

M=0

0.1

0.2

0.3

-16

-14

-12

Cpmin2

1

1

M

CC

p

p

-

-5

-4

--Cp

.

0.5

0.6

0.7M

-10

-8

-6

-2

-1

.

0.9 -4

-2

0

1

0.0 0.2 0.4 0.6 0.8 1.0x/c

0 0.5 1M

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PRESSURECOEFFIENTWHERETHELOCALMACHNUMBERIS1

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PRESSURECOEFFIENTWHERETHELOCALMACHNUMBERIS1

)1(11

12

21

M

-16

)1(2

12

2

1

M

CR

-14

-12

CpCR

-10

-8

-

-4

-2

0

0 0.2 0.4 0.6 0.8 1M

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)1(11 12

21

M

2

minmin

1

1

M

CpCp

-16

)1(212

21 M

CR

M

-14

-12

-

-8

-

MCR

-4

-2

0

0 0.2 0.4 0.6 0.8 1M

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)1(11 12

21

M

2

minmin

1

1

M

CpCp

-16

)1(212

21 M

CR

-14

-120012at8de .-

-8

-

MCR MCR

-4

-2

.

0

0 0.2 0.4 0.6 0.8 1M

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M=0.5

INVISCIDCALCULATION

= .

.

Ilan Kroo and J Alonso Stanford Universit

http://adg.stanford.edu/aa241/drag/dragrise.html

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ShockInduced

Separation

www.hq.nasa.gov/pao/History/SP-

440/ch7-2.htm

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NACA2315

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NACA2315

M

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11/25

Sweep

T eAreaRu e

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DesignedtomaximizeMDIV

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NACA0012at2.3deg. oe ng at eg.

0.8

0.4

p L .L .

0.0

0.4

0 0.5 1 0 0.5 1

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htt : oea.larc.nasa. ov PAIS Conce t2R

eality/supercritical.html

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8/10/2019 22 - Transonic Aerodynamics(1).pdf

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cosMM n

M

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cosMM n

M

R.T.Jones,HighSpeedWingTheory,

PrincetonUniversity

Press,

1960

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EffectsonLift

M

cosMM n

M

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2cos2

22

cos1 M

L

cosMM n

M

FigureA,4forg,P42

R.T.Jones,HighSpeedWingTheory,

PrincetonUniversity

Press,

1960

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2cos2

22

cos1 M

L

cosMM n

M

FigureA,4h,P43

R.T.

Jones,

HighSpeedWingTheory,

PrincetonUniversityPress,1960

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THESEARSHAACKBODY

2/32)/(18

)( LxV

xA

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TheAreaRule

Whitcomb,R.,1952AStudyoftheZeroLiftDragRise

CharacteristicsofWingBodyCombinationsNearthe

SpeedofSound,NACA

RM

L52H08

8/10/2019 22 - Transonic Aerodynamics(1).pdf

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8/10/2019 22 - Transonic Aerodynamics(1).pdf

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747200B(AirForce1),MaxMach0.89

747

400,

Max

Mach

0.92

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Atsu ersonicMachnumberstheAreaismeasured

along

the

Mach

plane

instead

of

perpendicular

to

the

flightdirection

p ma s apes ormoregenera requ remen s efinitebaseareas,arearequirementsatparticularcross

sections)

aregiven

by

W.T.

Lord

and

E.

Eminton in

SlenderBodiesofMinimumWaveDrag,JournaloftheAeronauticalSciences,August,1954,pages569

. . ,http://www.aoe.vt.edu/~mason/Mason_f/MRsoft.html#MINDRAG