Numerical Simulation Study on Flow Field of Single Stage Transonic Compressor Based on QCR-Modified Turbulence Model

The internal flow field of transonic aero-compressors is highly complex due to the presence of shock waves, vortices, and turbulent boundary layers, which complicate experimental investigation. The Reynolds-Averaged Navier-Stokes (RANS) turbulence model is commonly employed in engineering because of its effectiveness and operability in addressing multifaceted flow issues in transonic compressors. This study utilizes the RANS method to analyze the National Aeronautics and Space Administration (NASA) Stage 35 single-stage transonic compressor. It employs the standard Spalart-Allmaras (SA) model, the k-ω Shear Stress Transport (SST) model, and modified models using the Quadratic Constitutive Relation (QCR). The performance of these models is compared to assess their ability to capture complex flow characteristics of the single-stage transonic compressor and to highlight the prospects and limitations of each model in compressor calculations. The results show that the errors in peak efficiency measurements of Stage 35, as determined by the SA, SST, SA-QCR, and SST-QCR turbulence models compared to experimental observations, are 1.25%, 1.15%, 0.73%, and 1.0%, respectively. The errors in the near-stall pressure ratio are 1.17%, 1.33%, 0.34%, and 0.3%, respectively. The QCR-modified models yield efficiency and pressure ratio calculations that are closer to the experimental observations than those produced by the SA and SST models. The QCR-modified models demonstrate enhanced applicability to unsteady anisotropic flows in transonic compressors, particularly in interactions involving tip clearance vortices and shock waves/turbulent boundary layers. Compared to traditional linear eddy-viscosity models, these modifications effectively suppress flow separation and improve the prediction accuracy of complex flow fields.