Vortex-airfoil interaction is studied numerically, which causes one of the primary sources of mechanical vibration and aerodynamic noise generation. In this study, a Vortex-In-Cell(VIC) method is used for the calculation of the velocity field. The VIC method, originally developed for a free vorticity field, is applied to the body-vortex interaction by using a body fitted coordinates transformation. A FACR algorithm for a Poisson equation is used to solve the stream function-vorticity equation. The flow field is assumed to be inviscid, incompressible and two dimensional. The unsteady surface pressure is obtained from the unsteady Bernoulli equation and the pressure field near the airfoil is obtained by solving the Pressure-Poisson equation. Vortex trajectory, lift, drag are computed for Rankine and Gaussian distributed incident vortices. At each time step, wake vortices are shed from the trailing edge of the airfoil and the strengths are determined by using the conservation of the circulation and the unsteady Kutta condition. The results show that the VIC method is faster than the discrete vortex method and the distortion and the split of the incident vortex, during the interaction, are predicted reasonably well compared with the other data.
