Computational Fluid Dynamics, axial compressors, Cartesian cut-cell, boundary layer mesh
Axial compressors are used extensively in the energy, power, and transportation industries. Computational Fluid Dynamics (CFD) has been widely used in research and development of dynamic compressors. CFD modeling for such designs often presents great challenges in terms of meshing and computational cost due to moving parts with complex shapes, tiny gaps, and a large range of length scales and time scales to resolve. In this work, a Cartesian cut-cell based method with adaptive mesh refinement (AMR) is used to study Rotor 67, a transonic axial compressor design from NASA. The adopted method is demonstrated to be easily implemented and copmutationally efficient through a mesh convergence study, largely due to the advantage of an autonomously generated Cartesian cut-cell grid and AMR. Additionally, a boundary layer mesh can be used in conjunction with the Cartesian cut-cell mesh in order to resolve the near-wall flow more efficiently. Both the frozen-rotor approach with a single non-inertial reference frame (SRF) and a moving-rotor approach in a single inertial reference frame are used for the computation of the global pressure ratio and the isentropic efficiency as well as the local flow velocity, pressure, and temperature. Results show great grid convergence and good agreement with previously published experimental data for multiple operating conditions in terms of both global and local flow quantities.