HIgh Fidelity Modeling of Blade Row Interaction in a Transonic Compressor

In order to accurately model the physics associated with losses in a transonic compressor, a time-accurate simulation of a transonic compressor rig was developed. Initially phase-lag simulations were conducted to determine required time stepping and grid re nement to capture the blade row interactions. These parameters were used to develop quarter annulus simulations to investigate the physics involved in the rotor bow shock interaction with a highly loaded upstream blade row and its e ect on the compressor. Three di erent axial spacings between the rotor and the upstream blade row have been simulated corresponding to the experimental rig. Details of the unsteady and time-averaged ow eld are presented and described. Among the many ow features resolved in the simulations was a suction side separation bubble in the upstream stator blade row that forms and collapses as a result of di usion and passing pressure waves.