【摘 要】
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With the increase of blade loading,the loss prediction model used in the design process needs refinement and improvement to meet the requirement of high-performance design.For the turbine design,most
【机 构】
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Department of Energy and Power Engineering,Tsinghua University
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With the increase of blade loading,the loss prediction model used in the design process needs refinement and improvement to meet the requirement of high-performance design.For the turbine design,most of existing profile loss models are developed for subsonic and transonic cases and their accuracy in high Mach number flow are limited.The primary research interest of this work is to study the flow mechanism of turbine cascade with high Mach number and the related profile loss.In this work,a transonic turbine cascade with strong shock wave is numerically studied with Reynolds Averaged Navier-Stokes(RANS).Also,to overcome the limitations of RANS modeling,Delayed Detached Eddy Simulation(DDES)type high-fidelity turbulence simulation is also conducted.Based on the numerical results,the primary loss sources,including the profile loss,the trailing loss and the shock loss are analyzed and results from existing loss models are assessed.The results from current work may help to develop improved profile loss model for the design of turbine cascade working in the high Mach number regime.
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