A new numerical method——a disturbance vortex method——is presented to simulate the rotor/sta-tor interaction in tarbomachinery. By decomposing flow quantities into the averaged and the disturbance ones, the La-grangian vortex method and the deterministic vortex scheme are used to capture the convective process of the disturbance vortex and to approximate the viscous diffusion process, respectively. The application of Baldwin-Lomax turbulence model to wakes is developed so as to overcome the difficulty in continuously tracing the moving wake centerlines encountered by other numerical methods, and the defect such as the much higher calculated viscosity in the outer region than that in the boundary regions. The agreement between the computational and experimental results is generally good, which shows that the present method is reliable. A new numerical method - a disturbance vortex method - is presented to simulate the rotor / sta-tor interaction in tarbomachinery. By decomposing flow quantities into the averaged and the disturbance ones, the La-grangian vortex method and the deterministic vortex scheme are used to capture the convective process of the disturbance vortex and to approximate the viscous diffusion process, respectively. The application of Baldwin-Lomax turbulence model to wakes is developed so as to overcome the difficulty in continuously tracing the moving wake centerline encountered by other numerical methods , and the defect such as the much higher calculated viscosity in the outer region than that in that in the boundary regions. The agreement between the computational and experimental results is generally good, which shows that the present method is reliable.