Simulating Cooling Injection Effect of Trailing Edge of Gas Turbine Blade on Surface Mach Number Distribution of Blade

Document Type: Research Paper


Department of Aerospace, Maleke Ashtar University of Technology, Tehran, Iran


In this research, a gas turbine blade cascade was investigated. Flow analysis around the blade was conducted using RSM and RNG.K-ε turbulence modeling and it is simulated by Fluent software. The results were considered for the cases as Mach number loss at the trailing edge of blade caused by vortexes that were generated at the end of blade. Effect of cooling flow through the trailing edge on the Mach number distribution was also studied at the blade surface. Present results using RSM and RNG. K-ε turbulence modeling showed that the agreement was good and the capability of the applied model was strong enough to analyze such a complicated flow behavior. According to results from the Mach number distribution on the blade surface, air injection reduces the flow loss at the trailing edge. Comparison of the results shows that air injection at a rate of 3 percent of inlet total air to blade row make changes location of shock on the surface of blade and the loss in turbine blade decreases about 0.7%.


Main Subjects

[1] Dunham, J., and Came, P.M., “Improvements to the Ainley-Mathieson Method of Turbine Performance Prediction”, Transaction of the ASME, J. Eng. for Power, Ser. A, Vol. 92, pp. 252-256, (1970).


[2] Pritchard, L.J., “An Eleven Parameter Axial Turbine Airfoil Geometry Model”, ASME 85- GT-219, Tech. Report, (1985).


[3] Leonard, D., and Van Den Braembussche, R.A., “Inverse Design of Compressor and Turbine Blades at Transonic Flow Condition”, the ASME Int. Gas Turbine and Aeroengine Congress and Exhibition, Cologne, Germany, ASME–92- GT-430, (1992).


[4] Denton, J.D., “An Improved Time-marching Method for Turbo Machinery Flow Calculation”, ASME J. Eng. for Power, Vol. 105, pp. 514- 524, (1983).


[5] Joly, M., Verstraete, T.,  and Paniagua, G., “Differential Evolution based Soft Optimization to Attenuate Vane–rotor Shock Interaction in High-pressure Turbines”, Applied Soft Computing, Vol. 13, pp. 1882–1891, (2013).


[6] Aminossadati, S. M., and Mee, D. J., “An Experimental Study on Aerodynamic Performance of Turbine Nozzle Guide Vanes with Trailing-edge Span-wise Ejection”, ASME, Journal of Turbo Machinery, Vol. 135, pp. 031002.1–2, (2013).


[7] Barigozzi, G., Ravelli, S., Armellini, A., Mucignat, C., and Casarsa, L., “Effects of Injection Conditions and Mach Number on Unsteadiness Arising within Coolant Jets over a Pressure Side Vane Surface”, International Journal of Heat and Mass Transfer, Vol. 67, pp. 1220–1230, (2013).


[8] Uzol, O., and Camci, C., “Aerodynamic Loss Characteristics of a Turbine Blade with Trailing Edge Coolant Ejection: Part2-External Aerodynamics, Total Pressure Losses, and Predictions”, ASME, Journal of Turbo Machinery, Vol. 132, No. 2, pp. 249-257, (2001).


[9] El-Gendi, M., Lee, K. and Lee, S., “Comparison between Steady and Unsteady Flow Predictions through High Pressure Turbine Cascade”, KSME-JSME Thermal and Fluids Engineering Conference, GSF26-020, (2013).


[10]  Horbach, T., Schulz, A., and Bauer, H., “Trailing Edge Film Cooling of Gas Turbine Airfoils-effects of Ejection Lip Geometry on Film Cooling Effectiveness and Heat Transfer”, Int. Symp. on Heat Transfer in Gas Turbine Systems, Antalya, Turkey, (2009).


[11]  Ligrani, Ph., “Aerodynamic Losses in Turbines with and without Film Cooling, as Influenced by Mainstream Turbulence, Surface Roughness, Airfoil Shape, and Mach Number”, Hindawi Publishing Corporation, International Journal of Rotating Machinery, Article ID 957421, 28 pages, Vol. (2012).


[12]  Patankar, S.V., “Numerical Heat Transfer and Fluid Flow”, Emisphere Publishing Corporation, London, pp. 214, (1980).


[13]  Choudhury, D., “Introduction to the Renormalization Group Method and Turbulence Modeling”, Tech. Memorandum, Fluent Incorporated, TM-107, pp. 70, (1993).


[14]  Saniei Nejad, M., "Comprehensive Investigation of k-ε and k-ω Turbulence Models in Simulation Turbulent Supersonic Boundary Layer Generated over Smooth and Rough Flat Plates at Very High Reynolds Numbers", Journal of Fluid Mechanics and Aerodynamics, Vol. 1, No. 2, pp. 55-72, (2013). (In Persian)


[15]  Launder, B.E., Reece, G.J., and Rodi, W., “Progress in the Development of a Reynolds Stress Turbulence Closure”, Journal of Fluid Mechanics, Vol. 68, pp. 537–566, (1975).