Large eddy simulation of free-stream turbulence effects on heat transfer to a high-pressure turbine cascade

Abstract

Large eddy simulation of an uncooled, transonic, linear high-pressure turbine vane cascade has been pursued using a high-order numerical method with about 83 million grid points. Heat transfer and boundary layer development on the surface of the blade are investigated in the presence of inflow turbulence. Quantitative comparisons with the experiments of Arts et al. (Tech. Note 174, von Kármán Institute for Fluid Dynamics, Belgium, 1990) show excellent agreement. The distortion of vortices from the inflow turbulence in the cascade passage leads to the formation of long streamwise streaky structures, leading to transition of suction-side boundary layer. Significant heat transfer augmentation is seen on both the pressure and suction sides because of the presence of these structures.

Keywords:

• high-pressure turbine (HPT)
• heat transfer
• boundary layer transition

Acknowledgements

R. Bhaskaran would like to thank Dr. S. Nagarajan for helpful discussions during the development of the overset LES solver based on a code he had originally developed. The authors would like to thank Dr. R. Pecnik for his assistance in obtaining RANS-based initial solution. R. Bhaskaran would like to acknowledge helpful discussion with Prof. G. Iaccarino on the overset mesh topology. Partial support for this work from the Air Force Office of Scientific Research (AFOSR) and computational resources provided by the Army Research Laboratory (ARL) is gratefully acknowledged.