Integrated RANS-LES Simulation of NASA Stage 35 Compressor

Integrated RANS-LES of the NASA stage 35 compressor and a diffuser: the compressor stage is computed with the RANS flow solver TFLO, the subsequent diffuser with the LES flow solver CDP. Here, we look at the vorticity magnitude distribution at the 50% clip plane of the stator. Again, we can identify the wakes of the stator passing the interface. The different description of turbulence in the two mathematical approaches is apparent. While on the RANS side the turbulence is modeled in a turbulence model and cannot be seen in the vorticity distribution, on the LES side the fine scale turbulence is regenerated and can be identified as small-scale structures in the LES solution.

Integrated RANS-LES Computations in Gas Turbines: Compressor-Diffuser, J. U. Schlüter, X. Wu, S. Kim, J. J. Alonso, and H. Pitsch, AIAA-2004-0369, 42nd Aerospace Sciences Meeting and Exhibit Conference, January 2004.