A numerical study was performed to simulate the flow and heat transfer of impingement cooling on the leading edge of a turbine blade. Calculations were done by using a commercial CFD software CFX11.0 to solve Reynolds-averaged N-S equations in conjunction with the SST κ-ω two-equation turbulence model with an overall accuracy of the second order. The influences of four jet nozzle diameters at the same mass flow rate were considered for a target surface stretched by the middle cross section of the internal leading edge of a typical modern gas turbine blade. The result shows that the Nusselt number at the turbine blade leading edge and the streamwise average Nusselt number are more even when the jet nozzle diameter is larger
especially from the middle span to the tip of the blade. The minimum values of Nusselt number of the turbine blade leading edge and streamwise average Nusselt number will increase with the jet nozzle diameter
indicating that larger jet nozzle diameters will improve the performance of impingement cooling on the leading edge of a turbine blade.
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references
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