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