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http://www.iaeme.com/IJMET/index.
International Journal of Mechanical Engineering and Technology (IJMET)Volume 8, Issue 5, May 2017, pp.
Available online at http://www.iaeme.com/IJME
ISSN Print: 0976-6340 and ISSN Online: 0976
© IAEME Publication
STUDY OF HEAT TRANSF
RECTANGUL
K.Rakesh Sai, D.Gowru Naidu,
Department of Mechanical Engineering
ABSTRACT
Gas turbine plays an important role in present day industries. These turbines are
being widely used for the generation of power in large scale and also in the aircraft
propusion. The main challenge is to increase the performance and efficiency o
gas turbines and this can be done by raising the inlet temperature of the turbine. Now
a days gas turbine became more advanced and the inlet temperatures are as high as
17000c, where as the blade materials can withstand
compressor in the turbine extracts pressure in the form of a cooling air temperature
ranging 6500c. This cooling air is going to pass through the blade airfoil sections to
lower the temperature to 10000c which is safe for the operation of engine.
The gas turbine blade consists of cooling passages which are very complex, so it is
difficult for designers to accurately predict the metal temperature. The
aerothermodynamics in these airfoil sections are complex and there exists a large
thermal gradient through out the blade profile and hence the heat transfer coefficients
will be high. The heat transfer on the surfaces of the blade passages increases as the
flow enters into turbine and accelerates around the blade. For any type of complex
flows and high for high inlet temperatures designers need extensive experimental and
numerical data to help them in developing efficient cooling techniques. Detailed hot
gas path , heat transfer distribution , temperature distribution will help in developing
efficient airfoil section profiles.
Practically ,it is very complex to obtain the experimental data on the heat transfer
in thin airfoil sections of the turbine blade. The experiments were carried out on a
rectangular duct of aspect ratio 2:1. Air is used as a working flui
part is going to perform in ANSYS Workbench by using Fluent Flow analysis.
Key words: Reynolds Number, Nusselts Number,
Velocities, Heat Transfer Coefficient
Cite this Article: K.Rakesh Sai, D.Gowru Naidu, G.Balu Mahendra,
Y.V.Satyanarayana and CH.Siva Krishna
Rectangular Duct in A Gas Turbine
and Technology, 8(5), 2017
http://www.iaeme.com/IJMET/issues.asp?JType=IJMET&VType=8&IType=5
IJMET/index.asp 490 [email protected]
International Journal of Mechanical Engineering and Technology (IJMET) 2017, pp. 490–495, Article ID: IJMET_08_05_052
http://www.iaeme.com/IJMET/issues.asp?JType=IJMET&VType=8&IType=5
6340 and ISSN Online: 0976-6359
Scopus Indexed
TUDY OF HEAT TRANSFER THROUGH
RECTANGULAR DUCT IN A GAS TURBINE
Gowru Naidu, G.Balu Mahendra, Y.V.Satyanarayana,
Krishna
Mechanical Engineering, KL University, AP,
Gas turbine plays an important role in present day industries. These turbines are
being widely used for the generation of power in large scale and also in the aircraft
propusion. The main challenge is to increase the performance and efficiency o
gas turbines and this can be done by raising the inlet temperature of the turbine. Now
a days gas turbine became more advanced and the inlet temperatures are as high as
17000c, where as the blade materials can withstand a temperature up to 13500c. Th
compressor in the turbine extracts pressure in the form of a cooling air temperature
ling air is going to pass through the blade airfoil sections to
lower the temperature to 10000c which is safe for the operation of engine.
s turbine blade consists of cooling passages which are very complex, so it is
difficult for designers to accurately predict the metal temperature. The
aerothermodynamics in these airfoil sections are complex and there exists a large
h out the blade profile and hence the heat transfer coefficients
will be high. The heat transfer on the surfaces of the blade passages increases as the
flow enters into turbine and accelerates around the blade. For any type of complex
gh inlet temperatures designers need extensive experimental and
numerical data to help them in developing efficient cooling techniques. Detailed hot
gas path , heat transfer distribution , temperature distribution will help in developing
section profiles.
Practically ,it is very complex to obtain the experimental data on the heat transfer
in thin airfoil sections of the turbine blade. The experiments were carried out on a
rectangular duct of aspect ratio 2:1. Air is used as a working fluid. All the analysis
part is going to perform in ANSYS Workbench by using Fluent Flow analysis.
Reynolds Number, Nusselts Number, Average Temperatures, Inlet
Heat Transfer Coefficient.
K.Rakesh Sai, D.Gowru Naidu, G.Balu Mahendra,
Y.V.Satyanarayana and CH.Siva Krishna Study of Heat Transfer Through
Rectangular Duct in A Gas Turbine. International Journal of Mechanical Engineering
), 2017, pp. 490–495.
com/IJMET/issues.asp?JType=IJMET&VType=8&IType=5
T&VType=8&IType=5
ER THROUGH
GAS TURBINE
Y.V.Satyanarayana, CH.Siva
India.
Gas turbine plays an important role in present day industries. These turbines are
being widely used for the generation of power in large scale and also in the aircraft
propusion. The main challenge is to increase the performance and efficiency of the
gas turbines and this can be done by raising the inlet temperature of the turbine. Now
a days gas turbine became more advanced and the inlet temperatures are as high as
a temperature up to 13500c. The
compressor in the turbine extracts pressure in the form of a cooling air temperature
ling air is going to pass through the blade airfoil sections to
lower the temperature to 10000c which is safe for the operation of engine.
s turbine blade consists of cooling passages which are very complex, so it is
difficult for designers to accurately predict the metal temperature. The
aerothermodynamics in these airfoil sections are complex and there exists a large
h out the blade profile and hence the heat transfer coefficients
will be high. The heat transfer on the surfaces of the blade passages increases as the
flow enters into turbine and accelerates around the blade. For any type of complex
gh inlet temperatures designers need extensive experimental and
numerical data to help them in developing efficient cooling techniques. Detailed hot
gas path , heat transfer distribution , temperature distribution will help in developing
Practically ,it is very complex to obtain the experimental data on the heat transfer
in thin airfoil sections of the turbine blade. The experiments were carried out on a
d. All the analysis
part is going to perform in ANSYS Workbench by using Fluent Flow analysis.
Average Temperatures, Inlet
Study of Heat Transfer Through
al of Mechanical Engineering
com/IJMET/issues.asp?JType=IJMET&VType=8&IType=5
K.Rakesh Sai, D.Gowru Naidu, G.Balu Mahendra, Y.V.Satyanarayana and CH.Siva Krishna
http://www.iaeme.com/IJMET/index.asp 491 [email protected]
1. INTRODUCTION
The purpose of gas turbine technology is to extract the maximum energy from the high
temperature high pressure gases produced by combustor. This could be achieved by
improving the thermal efficiency of the gas turbine engine. Attempts were being made to
increase the power output and thermal efficiency of a gas turbine engine by operating turbine
at elevated temperatures as it is understood that the efficiency of gas turbine is a direct
function of turbine inlet temperature.
Turbine blades are the individual components which make up the turbine section of a gas
turbine engine and are responsible for extracting energy from the high temperature, high
pressure gases produced by the combustor. The turbine blades are often the limiting
component and were considered as the critical components of the gas turbine engines in
which failures occur frequently.
Gas turbines play a vital role in the today’s industrialized society, and as the demands for
power increase, the power output and thermal efficiency of gas turbines must also increase.
Modern high-speed aero-engines operate at elevated temperatures about 2000 K to achieve
better cycle efficiencies. However, the presently available alloys cannot resist temperatures
much higher than 1350 K. Internal cooling techniques for gas turbine blades have been
studied for several decades. The internal cooling techniques of the gas turbine blade includes:
jet impingement, rib tabulated cooling, and pin-fin cooling which have been developed to
maintain the metal temperature of turbine vane and blades within acceptable limits in this
harsh environment.
2. MODELLING & DESIGNING OF DUCT
Modelling and designing are the key elements for any analysis and experimental procedure.
This process can be done by using any of the modelling software .
Even in analysis software also it is possible to model a simple geometry. In ANSYS
workbench we can draw our geometry. Cross section of the rectangular duct is 50 × 25 mm
length of the duct is 500mm.
Study of Heat Transfer Through Rectangular Duct in A Gas Turbine
http://www.iaeme.com/IJMET/index.
3. EXPERIMENTAL RESULTS
Temperature varying with position ‘m’
Reynolds number 5000
Reynolds number 10000
Study of Heat Transfer Through Rectangular Duct in A Gas Turbine
IJMET/index.asp 492 [email protected]
EXPERIMENTAL RESULTS
emperature varying with position ‘m’
Study of Heat Transfer Through Rectangular Duct in A Gas Turbine
K.Rakesh Sai, D.Gowru Naidu, G.Balu Mahendra, Y.V.Satyanarayana and CH.Siva Krishna
http://www.iaeme.com/IJMET/index.
Reynolds number 15000
Reynolds number 20000
K.Rakesh Sai, D.Gowru Naidu, G.Balu Mahendra, Y.V.Satyanarayana and CH.Siva Krishna
IJMET/index.asp 493 [email protected]
Reynolds number 20000
K.Rakesh Sai, D.Gowru Naidu, G.Balu Mahendra, Y.V.Satyanarayana and CH.Siva Krishna
Study of Heat Transfer Through Rectangular Duct in A Gas Turbine
http://www.iaeme.com/IJMET/index.asp 494 [email protected]
Table showing the results for our analysis
Reynolds number 5000 10000 15000 20000
Velocity inlet (m/s) 2.89 4.28 6.2 10.6
Temperature (K) 390 354.5 343 326
Heat transfer
coefficient (W/(m2•K)
10.16 15.05 20.12 24.65
Nusselts number 5.9 8.88 12.13 16.14
4. CONCLUSIONS
From this analysis we can conclude that as we increase the Reynolds number both the inlet
velocities and heat transfer coefficient increases , where as the temperatures decreased. The
heat transfer on the surfaces of the blade passages increases as the flow enters into turbine and
accelerates around the blade. For any type of complex flows of a turbines and for high inlet
temperatures, designers need extensive experimental and numerical data to help them in
developing efficient cooling techniques.
5. FUTURE SCOPE
Based on our present analysis in future we are going to work on getting some more extensive
experimental data such as detailed hot gas path heat transfer distribution , temperature
distribution. This will help in developing efficient airfoil section profiles and also we can
increase the efficiency of the gas turbine.
REFERENCES
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Lecture Series 1995-05, May 8-12 1995.
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McGraw-Hill Companies, New York (ISBN 0-07-118152-0).
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K.Rakesh Sai, D.Gowru Naidu, G.Balu Mahendra, Y.V.Satyanarayana and CH.Siva Krishna
http://www.iaeme.com/IJMET/index.asp 495 [email protected]
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