10
Indian J.Sci.Res.1(2) : 900-908, 2014 ISSN:2250-0138(Online) ISSN : 0976-2876 (Print) __________________________________ 1 Corresponding author EXPERIMENTAL INVESTIGATION OF ELECTROTHERMAL ANTI-ICING SYSTEM IN THE GAS TURBINE AIR INLET SYSTEM REZA TIRGAR a , MOHSEN KHOSHBAYANI b1 , MOHSEN MOTAHARI NEZHAD c a Department of Mechanical engineering, Kashan branch, Islamic Azad University, Kashan, Iran. b Department of Mechanical Engineering, Kashan branch, Islamic Azad University, Kashan, Iran. c Iran University of Science and Technology, Tehran, Iran. ABSTRACT In this study, a new method has been proposed for anti-icing of gas turbine inlet system. This method was examined by laboratory and numerical study. In experimental study a device was designed and fabricated after sample replacement of an electro-thermal system.Finally,usingFluent software, anumericalstudyhas been conductedonthe flow behavior. According to the results, the anti-icing system presented by electrothermal method is efficient for anti-icing at the entrance of air inlet of gas turbines of gas compressor stations. KEYWORDS: Anti-icing, Electrothermal method,Gas turbine, Numerical solution,Experimental study Turbine performance and component service life greatly depends on the ability of an air inlet system to reduce or eliminate contaminants entering the system. If these contaminants are not effectively removed, then fouling, erosion, corrosion and compressor blades damage will be the result (Goulding et al., 1990). Snow and ice crystals agglomerate quickly in an intake and cause blockage of the intake. The particle size in arctic environment varies from 0,01 µm to 10 µm(HILL, 2002). The ice on the blades can deteriorate air aerodynamic in the passages. So it is possible to experience an axial compressor flow stall and surge (Chappell and Grabe, 1974). The ice accretion can also cause mechanical damage to the compressor blades as a result of blades vibrations. In extreme cases, ice can shed due to vibratory and/or aerodynamic forces and the resulting impact of these pieces of ice are the hazardous foreign object damage (FOD) (Bagshaw, 1976).The primary aim for an icing protection system is to prevent or limit ice accretion within the gas turbine intake system. The complexities of inlet system for stationary gas turbine applications often limit the possibility of guaranteeing free icing inlet system. Electrothermal system consists of resistance wires are imbedded in rubber pads which are mounted on the icing surface which has to be protected (Chappell et al., 1974). This systems advantage is that it only heats the icing points (Chappell et al., 1974). However, it requires the exact critical points where ice can form. Since the ice forming process is very complex, it is difficult to determine these critical points. Therefore more than one electrical heater can be used to cover up all these points. B.F. Goodrich has developed an electrothermal system for the rotor blades of the Army Apache AH-64 helicopter. Electrothermal system consists of a source of electrically generated heat and a control system. The system pulverizes ice into small particles and removes layers of ice as thin as frost or as thick as an inch of glaze ice.Hongchang Electric Heater Products Factory, which has established in 1996, introduced heating components which are made of metal electrothermal film (Hamilton Sundstrand.,2006).In this research, we have studied changes in air temperature after entrance the channel and tried to reach to the ideal temperature for entering to axial compressor in a range of (5°c -10°c). the aim of this research is to study experimentally the anti-icing system by electrothermal method at the channel inlet air. EXPERIMENTAL SETUP We used three sciences, mechanical engineering, materials engineering and electrical engineering in construction of the device. In this device, the temperature of the desired location is measured by temperature sensors and then a switching command goes to electronic relay by a microcontroller. Connecting the relay the power reaches to electric element practically and turns it on and warms the channel interior environment. Next, whenever the temperature of the location increases to an especial point, a power cut command goes to the relay. There are some pictures of this device in Figure 1. In general, with this system, the temperature of the desired area can be controlled and fixed between desired minimum temperature and desired maximum temperature. This will include the following results: a) Prevents practically of freezing air molecules inside the channel and before the turbine blades. b) The temperature of desired area can be controlled and stabilized. c) If the turbine has the best performance for a certain amount of inlet temperature, that temperature is achievable under control.

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Indian J.Sci.Res.1(2) : 900-908, 2014

ISSN:2250-0138(Online)

ISSN : 0976-2876 (Print)

__________________________________ 1Corresponding author

EXPERIMENTAL INVESTIGATION OF ELECTROTHERMAL ANTI-ICING SYSTEM IN THE

GAS TURBINE AIR INLET SYSTEM

REZA TIRGAR

a, MOHSEN KHOSHBAYANI

b1, MOHSEN MOTAHARI NEZHAD

c

aDepartment of Mechanical engineering, Kashan branch, Islamic Azad University, Kashan, Iran.

bDepartment of Mechanical Engineering, Kashan branch, Islamic Azad University, Kashan, Iran.

cIran University of Science and Technology, Tehran, Iran.

ABSTRACT

In this study, a new method has been proposed for anti-icing of gas turbine inlet system. This method was examined by laboratory and

numerical study. In experimental study a device was designed and fabricated after sample replacement of an electro-thermal

system.Finally,usingFluent software, anumericalstudyhas been conductedonthe flow behavior. According to the results, the anti-icing system

presented by electrothermal method is efficient for anti-icing at the entrance of air inlet of gas turbines of gas compressor stations.

KEYWORDS: Anti-icing, Electrothermal method,Gas turbine, Numerical solution,Experimental study

Turbine performance and component service life

greatly depends on the ability of an air inlet system to reduce

or eliminate contaminants entering the system. If these

contaminants are not effectively removed, then fouling,

erosion, corrosion and compressor blades damage will be the

result (Goulding et al., 1990). Snow and ice crystals

agglomerate quickly in an intake and cause blockage of the

intake. The particle size in arctic environment varies from 0,01

µm to 10 µm(HILL, 2002). The ice on the blades can

deteriorate air aerodynamic in the passages. So it is possible to

experience an axial compressor flow stall and surge (Chappell

and Grabe, 1974). The ice accretion can also cause mechanical

damage to the compressor blades as a result of blades

vibrations. In extreme cases, ice can shed due to vibratory

and/or aerodynamic forces and the resulting impact of these

pieces of ice are the hazardous foreign object damage (FOD)

(Bagshaw, 1976).The primary aim for an icing protection

system is to prevent or limit ice accretion within the gas

turbine intake system. The complexities of inlet system for

stationary gas turbine applications often limit the possibility of

guaranteeing free icing inlet system. Electrothermal system

consists of resistance wires are imbedded in rubber pads which

are mounted on the icing surface which has to be protected

(Chappell et al., 1974). This systems advantage is that it only

heats the icing points (Chappell et al., 1974). However, it

requires the exact critical points where ice can form. Since the

ice forming process is very complex, it is difficult to

determine these critical points. Therefore more than one

electrical heater can be used to cover up all these points. B.F.

Goodrich has developed an electrothermal system for the rotor

blades of the Army Apache AH-64 helicopter. Electrothermal

system consists of a source of electrically generated heat and a

control system. The system pulverizes ice into small particles

and removes layers of ice as thin as frost or as thick as an inch

of glaze ice.Hongchang Electric Heater Products Factory,

which has established in 1996, introduced heating components

which are made of metal electrothermal film (Hamilton

Sundstrand.,2006).In this research, we have studied changes in

air temperature after entrance the channel and tried to reach to

the ideal temperature for entering to axial compressor in a

range of (5°c -10°c). the aim of this research is to study

experimentally the anti-icing system by electrothermal method

at the channel inlet air.

EXPERIMENTAL SETUP

We used three sciences, mechanical engineering,

materials engineering and electrical engineering in

construction of the device. In this device, the temperature of

the desired location is measured by temperature sensors and

then a switching command goes to electronic relay by a

microcontroller. Connecting the relay the power reaches to

electric element practically and turns it on and warms the

channel interior environment. Next, whenever the temperature

of the location increases to an especial point, a power cut

command goes to the relay. There are some pictures of this

device in Figure 1.

In general, with this system, the temperature of the desired

area can be controlled and fixed between desired minimum

temperature and desired maximum temperature. This will

include the following results:

a) Prevents practically of freezing air molecules inside

the channel and before the turbine blades.

b) The temperature of desired area can be controlled and

stabilized.

c) If the turbine has the best performance for a certain

amount of inlet temperature, that temperature is achievable

under control.

KHOSHBAYANI ET AL EXPERIMENTAL INVESTIGATION OF ELECTROTHERMAL ANTI

Indian J.Sci.Res.1(2) : 900-908, 2014

Figure 1. Pictures oflaboratory apparatus

(A) the View from the Top (B)the view from

THE DEVICE PERFORMANCE

At first, we simulated the conditions of axial compressor

responsible to suction inlet air by a 12 Volt DC

make the control system start up, first the amount of minimum

temperature is given to microcontroller by turnkey and this

amount of temperature will be saved in the memory of

microcontroller. Afterward the amount of maximum

temperature is given and saved as well. Then the control

system starts up. Need to mention that all control s

displayed on the existing LCD screen by the microcontroller.

This orbit measures and displays the air temperature passing

though element on the screen at any moment by LM35DZ

temperature sensor. This measured temperature gets into the

control system as a feedback. In control system by an

ATMEGA 32 microcontroller all necessary processes

Figure 2. The schematic orbit designed by Proteus software.

EXPERIMENTAL INVESTIGATION OF ELECTROTHERMAL ANTI-ICING SYSTEM IN THE GAS..

Pictures oflaboratory apparatus

the View from the Top (B)the view from the front.

At first, we simulated the conditions of axial compressor

olt DCmotor. To

make the control system start up, first the amount of minimum

given to microcontroller by turnkey and this

amount of temperature will be saved in the memory of

microcontroller. Afterward the amount of maximum

temperature is given and saved as well. Then the control

system starts up. Need to mention that all control stages are

displayed on the existing LCD screen by the microcontroller.

This orbit measures and displays the air temperature passing

though element on the screen at any moment by LM35DZ

temperature sensor. This measured temperature gets into the

tem as a feedback. In control system by an

ATMEGA 32 microcontroller all necessary processes is done.

The microcontroller determines the on

electronic relay based on the amount of intake temperature. By

connected relay, electrical power ca

electrical element and an off command goes to the relay, the

element power flow is cut and the temperature decreases

because of the air suction by turbine blades and low

temperature of the air outside. This increasing and decreasing

temperature is being controlled so that the temperature of the

desired point remains in ideal range ever.

A 1000 (w) electric element also has been installed at the

entrance of channel on 2 rods insulated with mica and warms

the interior channel air by passing t

from the element. The schematic orbit designed by Proteus

software is shown in Figure 2.

The schematic orbit designed by Proteus software.

ICING SYSTEM IN THE GAS..

- 901 -

The microcontroller determines the on-off commands to

electronic relay based on the amount of intake temperature. By

connected relay, electrical power causes warming the

electrical element and an off command goes to the relay, the

element power flow is cut and the temperature decreases

because of the air suction by turbine blades and low

This increasing and decreasing

ature is being controlled so that the temperature of the

desired point remains in ideal range ever.

electric element also has been installed at the

entrance of channel on 2 rods insulated with mica and warms

the interior channel air by passing the air sucked by motor

from the element. The schematic orbit designed by Proteus

KHOSHBAYANI ET AL EXPERIMENTAL INVESTIGATION OF ELECTROTHERMAL ANTI-ICING SYSTEM IN THE GAS..

Indian J.Sci.Res.1(2) : 900-908, 2014 - 902 -

TECHNICAL NOTES OF THE ORBIT

a) The bobbin of electronical relay used in this orbit is induced

with 5 volt and is able to connect or disconnect 240 volts AC

up to 7 amper. To setup the relay, we used a NPN transistor as

stream buffer since the micro is unable to transmit the power

flow. If the micro commands connection, the interface

transistor is responsible to delivering the power flow to the

bobbin of the relay and makes the relay actuated to pass the

electricity to electrical element. Since bobbin of the relay is a

salafi load, so a reverse parallel diode has been used to avoid

flow impact. The following orbit has been used to setup bobbin via microcontroller (Fig.3).

Figure 3. Relay driver circuit microcontroller

b) LCD is connected to PORTC and various control stages are

displayed.

c) LM35DZ thermal sensor has incremental coefficient of 10 (

mv

c°) (10 millivolts per degree rise).

d) The amount of analog voltage resulting from thermal sensor

LM35DZ enters into the micro by PORTA and turns to

comprehensible digital content for microcontroller with the

help of a 10 bit ADC converter.

e) The software CodeVision AVR has been used to

programming the microcontroller and Proteus software for

simulating the desired schematic orbit.

Study the Experimental Results

In this section we are going to compare the results of

experimental testings with the results of Matlab and Fluent

softwares. In experimental conditions we can get the function

curve by checking and recording the machine output data

visible on the monitor, and also recording the related times.

Based on Matlab outputs, the system function graph and based

on Fluent outputs, the contour and the temperature graph are

achievable. Characteristics required for study are given in

Table 1.

Table 1. Characteristics required for study

Character Amount

Ain 25(cm) ×25(cm)

Lenght 50(cm)

Vin 7(m/s)

Pin 101325(pa)

Tin -4(G c)

ρair 1.225(kg/m3)

Inlet air with (-4°c)

In this section, using various recorded temperatures and the

related times,we can draw the air heating curve that enters

anti-icing system with -4 (°c) temperature. As shown in the

Figure 4, due to heat transfer from the elements to inlet air,

during 83 seconds the temperature reaches to +5(°c) and after

184 seconds will reaches to +10(°c). now the heating source

turns off temperature decreases to -4(°c) after 440(s).

KHOSHBAYANI ET AL EXPERIMENTAL INVESTIGATION OF ELECTROTHERMAL ANTI

Indian J.Sci.Res.1(2) : 900-908, 2014

Figure 4.

According to the Figure 5 and the results of the code writing in

Matlab, the sensor of the entrance channel of the turbine

shows -4(°c) temperature on the monitor. As a result, the

heating source turns on and starts to warming the cold inlet

air.After about 90(s) the temperature reaches to +5

color of the graph changes from blue to red so that shows

warming the air (as shown in Fig. 4). After 170

temperature reaches to +10(°c) that according to the study of

gas turbines used in pressure boosting station, including

Ziemence turbine, the ideal temperature for entering to the

Figure 5. The variation of inlet

0; -4

-6

-4

-2

0

2

4

6

8

10

12

0

Temperature(C)

0 50 100 150 200-4

-2

0

2

4

6

8

10

Temprature

( C)

Time(second)

Anti-Icing System

T( ) 4

57.228 (1 e )

t = − −

EXPERIMENTAL INVESTIGATION OF ELECTROTHERMAL ANTI-ICING SYSTEM IN THE GAS..

- c)

igure 5 and the results of the code writing in

Matlab, the sensor of the entrance channel of the turbine

temperature on the monitor. As a result, the

eating source turns on and starts to warming the cold inlet

the temperature reaches to +5(°c) and

color of the graph changes from blue to red so that shows

). After 170(s) the

that according to the study of

gas turbines used in pressure boosting station, including

Ziemence turbine, the ideal temperature for entering to the

axial compressor is also +10(°c). Thus the heating source turns

off by the microcontroller order an

again. During 270(s) the temperature again reaches to

+5(°c)After reaching a temperature of zero degrees Celsius,

heating elements turn on and cycle back to previous steps.

The following equation has been used to coding Matlab

software and then we attained different

temperature (°c) versus time (seconds) in static heat transfer

condition.

The variation of inlet - c)

83; 5

184, 10

261, 5

335; 0

440, -4

100 200 300 400 500

Time(second)

(1)4.575t

57.228

1000T( ) 4

57.228 (1 e )× −

ICING SYSTEM IN THE GAS..

- 903 -

. Thus the heating source turns

off by the microcontroller order and the temperature decreases

the temperature again reaches to

After reaching a temperature of zero degrees Celsius,

heating elements turn on and cycle back to previous steps.

The following equation has been used to coding Matlab

and then we attained different diagram of

temperature (°c) versus time (seconds) in static heat transfer

(1)

KHOSHBAYANI ET AL EXPERIMENTAL INVESTIGATION OF ELECTROTHERMAL ANTI-ICING SYSTEM IN THE GAS..

Indian J.Sci.Res.1(2) : 900-908, 2014 - 904 -

( ) ( )0

∂ ∂∂+ + =

∂ ∂ ∂

ρu ρvρ

t x y

Equations of Fluid flow

1.1. Mass conservation

The first law governing the fluid particle is Mass Conservation Law. Considering the mass balance for a fluid element, this law can

be explained so that the net rate of inlet mass flow to the fluid element should be equal to the rate of mass increasing in the fluid

element. It means with considering a fluid element we can write:

In the above equation, U is speed vector, u and v are components of speed vector and ρ is fluid density.

1.2. Momentum Equation

Newton’s second law expresses that the rate of momentum change of a fluid particle is equal to the resultant exerted forces.

Considering a fluid particle, the momentum equations can be shown like this.

( ) ∂∂ − += + +

∂ ∂yxxx

Mx

Du

Dt

τp τρ S

x y

( )

∂ − + ∂= + +

∂ ∂yy xy

My

Dv

Dt

p τ τρ S

y x In the above equations, p is pressure, ��� is body forces , and ��� is viscosity.

1.3. Energy Equation

The energy equation comes from the first thermodynamic law,

expresses that the rate of fluid particle energy changings is

equal to the sum of the heattransfer rate applied to the fluid

particle and the rate of work done on the fluid particle. This

equation is being presented as follow:

( ) ( ) ( ) ( ) ( )( )( ).

∂ ∂ ∂∂=− + + + + + +

∂ ∂ ∂ ∂yx xy yyxx

E

DE

Dt

uτ vτ vτuτρ div pU div k grad T S

x y x y

( )2 21

2= + +E i u v

The term SE defined as gravitational potential source and i as

internal energy.

1.4. Modeling Turbulence

In all applied streams of engineering, in low Reynolds

numbers, the stream is like layers and turns to turbulent mode

from quiet mode by transition from a specific Reynolds

number. In turbulent mode, each optional parameter φ can be

considered as a combination of permanent mean values φ and

fluctuant component φG.

a. Continuity equation

( ) 0∂

+ =∂ρdiv ρU

t

( ) 0∂

+ =∂

ρdiv ρU

t

(2)

(3)

(4)

(5)

(6)

(7)

(8)

KHOSHBAYANI ET AL EXPERIMENTAL INVESTIGATION OF ELECTROTHERMAL ANTI-ICING SYSTEM IN THE GAS..

Indian J.Sci.Res.1(2) : 900-908, 2014 - 905 -

b. Reynold transport equation

( ) ( ) ( )( )( ) ( )'2 ' '

.

∂ ∂∂ ∂ + = − + + − − + ∂ ∂ ∂ ∂

Mx

ρu ρuvρu pdiv ρuU div µ grad u S

t x x y

( ) ( ) ( )( )( ) ( )'2 ' '

. ∂ ∂∂ ∂

+ = − + + − − +∂ ∂ ∂ ∂

My

ρv ρu vρv pdiv ρvU div µ grad v S

t x y x

c. Scalar transport equation

( ) ( ) ( )( )( ) ( )' ' ' '

. ∂ ∂∂

+ = + − − +∂ ∂ ∂

Φ Φ

Φ ΦΦΦ Γ Φ

ρu ρvρdiv ρ U div grad S

t x y

d. Selecting model k-ω

RANS equations show the transfer just only for streams

quantities with all irregular flows scales. the method RAN has

been applied in most CFD calculations to calculate the

turbulent models like the standard k-ω model and its variants ,

the standard k- ε and its variants, and Reynolds stress model

(RSM) .

The standard k-ω model is based on transfer equations for the

kinetic energy (k) and irregular frequnce(ω) (Wilcox, 1988).

The most important weak of the k–ω model is its high

sensitivity to free flow conditions (Stamou and Katsiris, 2006).

SST model merges k–ε and k–ω models by using a synthesizer

(combiner)function (Menter, 1994). SST model activates the

k–ω model in the region close to the wall and k–ε model for

the rest of the flow. By this method, interesting near the wall

performance of k–ω model is used without its probability of

error due to its sensitivity to free flow. In recent assessment,

SST k–ω model has been used to simulate the temperature

inside the channel.

1.5. The geometry and boundary conditions

the geometry and boundary conditions of the question as

shown in figure 6, we installed six element 1000 Watt in the

channel opening to create a geometry similar to geometry of

the real system. 7803 cells have been created in the mesh

networks of this geometry. We considered the length and

width of the entrance that has square cross section and selected

the channel length of 50 (cm).

Figure 6. Mesh geometry

1.6. Temperature variation

According to Figure7, cold air containing ice crystal particles,

enters to the air suction chamber with 7 (m/s) speed and

269(k) temperature and after the crossing the power flow from

the elements reaches to its highest temperature of 290(k) equal

to 17(Gc). With time passing and getting the power flow away

from the elements air temperature will gradually warm,

decrease and stand in range of 278(k) to 284(k). After flowing

through the gooseneck and exit channel and reach the axial

compressor , the temperature reaches to almost constant

amount of 280(k). that is very close to the outlet air

temperature of the simulated system in previous section the

outlet air temperature of the simulated system in previous

section and is the ideal temperature. Significant note in this

contour is forming boundary layer in the inner wall of the

channel due to temperature gradients from heat exchange

process between the fluid and the wall. Speed is zero at the

wall and the heat transfer into the fluid occurs by conduction.

(9)

(10)

(11)

KHOSHBAYANI ET AL EXPERIMENTAL INVESTIGATION OF ELECTROTHERMAL ANTI-ICING SYSTEM IN THE GAS..

Indian J.Sci.Res.1(2) : 900-908, 2014 - 906 -

However, due to increasing air velocity in internal Arc, the

thermal boundary layer decreases and in the external Arc, due

to the slowdown air velocity the thermal boundary layer

increases. But with time passing and decreasing temperature,

the created thermal boundary layer will be identical.

Figure 7. Contourof temperature

Also according to the diagram of pressure variation inFigure

8, the temperature is zero at the left wall of channel and then

by moving to the right wall, increases and fixes in range of 2.5

cm to 22.5 cm after this region, the temperature gradually

decreases and reaches to zero till the right wall of outlet.

Figure 8. Diagram oftemperature changesdepending onthe width ofthe outletchannel

1.7. Pressure variation

Considering Figure 9, in pressure contour air enters the air

suction chamber with a pressure of 101325 Pascal and after

dealing with the elements, the pressure drops and in some

sections behind them, reaches to about 8000pascal regions

with relatively high pressure are in the inlet channel, and areas

with relatively low pressure are at the back of thermal

elements and boundary of right wall of the channel out put.

Based on experimental results in cold season we got

Randomly and during turbine operation in cold weather, the

pressure in the air suction chamber outlet and the axial

compressor inlet, the ideal pressure for proper operation of the

turbine, is in a range of 75000 psi to 90000psi.

Indian J.Sci.Res.1(2) : 900-908, 2014

ISSN:2250-0138(Online)

ISSN : 0976-2876 (Print)

__________________________________ 1Corresponding author

Figure 9. contour of pressure Variations

Figure 10. Diagram ofpressure varitiononthe width ofthe outletchannel

1.8. Velocity variation

As for Figure 11, from the previous path, this time the velocity

contours can only be seen by converting pressure to speed. the

velocity reaches its highest level in the distance between

elements 10(m/s) due to reduced cross section of the flow and

also in the inner are of gooseneck due to reduced pressure and

increased path curvature. The velocity also drops to its lowest

level 7(m/s), in the outer arc of gooseneck due to increased

pressure and reduced path curvature. According to equation

13, in which a is as acceleration and ρ as radius of curvature,

can be realized by increasing the radius of curvature, the speed

increases.

2

n

Va

ρ=

(12)

KHOSHBAYANI ET AL EXPERIMENTAL INVESTIGATION OF ELECTROTHERMAL ANTI

Indian J.Sci.Res.1(2) : 900-908, 2014

Figure 11.

Figure 12, shows the changes of air velocity vector inside the channel. As shown , the air velocity

amount in the outer are of the channel and the maximum amount in the inner arc of the channel.

Figure 12.

In Figure 13, the air velocity is zero in right and left walls of the channel outlet and in the middle of that, the

constant.

EXPERIMENTAL INVESTIGATION OF ELECTROTHERMAL ANTI-ICING SYSTEM IN THE GAS..

Contour of velocity variation

Figure 12, shows the changes of air velocity vector inside the channel. As shown , the air velocity vector has the minimum (smallest)

amount in the outer are of the channel and the maximum amount in the inner arc of the channel.

Contour of velocity variation

igure 13, the air velocity is zero in right and left walls of the channel outlet and in the middle of that, the

ICING SYSTEM IN THE GAS..

- 908 -

vector has the minimum (smallest)

igure 13, the air velocity is zero in right and left walls of the channel outlet and in the middle of that, the velocity is relatively

KHOSHBAYANI ET AL EXPERIMENTAL INVESTIGATION OF ELECTROTHERMAL ANTI-ICING SYSTEM IN THE GAS..

Indian J.Sci.Res.1(2) : 900-908, 2014 - 909 -

Figure 13. Diagram ofvelocity variation onthe width Ofthe outletchannel

CONCLUSIONS AND SUMMARY

In this study, a new method presented for anti-icing the

incoming cold air into air suction chamber of Gas turbines.

According to the novelty of the idea and absence of a similar

system for studying, we built up a laboratory simulation

system for experimental study and numerical solution. Based

on the results, this method is efficient for defrost cold air

entering the suction chamber of Gas turbines and suggested as

an appropriate method. However, to achieve optimal

arrangement of elements needs more study.

ACKNOWLEDGMENT

The authors consider the necessity to gratitude of Islamic

Azad University of kashan and also the national Iranian

Gas company due to their support and assistance in

carrying out this research.

REFERENCES

Goulding,C.H., Rasmussen, M.G., Fritz, F.M.; 1990.

Technical and Other Considerations for the Selection of Inlet

Air Filtration Systems for High-Efficiency Industrial

Combustion Turbines, ASME, 90-GT-176, Presented at the

Gas Turbine and Aeroengine Congress and Exposition.

HILL, D.G.T.; 2002. Gas Turbine Intake Systems in Unusual

Environments, ASME, 73-GT-38.

Chappell,M.S., Grabe,W.; 1974. Icing Problems on Stationary

Gas Turbine Powerplants, ASME.

Bagshaw, K.w.; 1976. Icing Problems-Review of Simulated

Ice Ingestion Tests, ASME, n76-GT-128.

Chappell, M. S. &Grabe, W.; 1974. Icing Problems on

Stationary Gas Turbine Powerplants, ASME.

Hamilton Sundstrand.; 2006. Ice Protection Control Systems,

A United Technologies Company, Dynamic Controls.

Wilcox DC.; 1988. Reassessment of the scale determining

equation for advanced turbulence models. AIAA Journal

26(11):1299–311.

Stamou, A., & Katsiris, I.; 2006. Verification of a CFD model

for indoor airflow and heat transfer. Building and

environment, 41(9): 1171-1181.

Menter, F. R.; 1994. Two-equation eddy-viscosity turbulence

models for engineering applications. AIAA journal, 32(8),

1598-1605.