Vortex simulation of rotor/stator interaction in turbomachinery

A new numerical method is presented in this paper to simulate rotor/stator interaction in turbomachinery by means of a vortex method based on a Lagrangian frame. The algorithm takes the result from steady solution as input, which gives an initial description of the unsteady disturbance flow field. To calculate the unsteady response to these disturbances, the Lagrangian vortex method is used to capture the convective process, and the deterministic vortex scheme to approximate the viscous diffusion process. The application of Baldwin-Lomax turbulence model in wakes is developed, to overcome difficulties such as the much higher calculated viscosity in the outer region than that in the boundary regions, and the difficulty in continuously tracing moving wake centerlines encountered when other numerical methods are used. Generally the agreement between the computational and experimental results is good. The sweeping characteristic of wakes, the influence of unsteadiness on incidence, and the decaying features of unsteady velocities and pressure are studied in the paper.