Abstract
Flows about a ball valve are simulated by the discrete vortex method. The flow is assumed to be axi-symmetric and formulated by a set of circular vortex rings. The formulation is performed by the Stokes stream function and the elliptic functions. Free vortices move due to induced velocity from other vortices, affect of viscosity diffusion and that by themselves. The self-induced velocity is evaluated by assuming that the vortex ring has finite-size core. The duct and the ball surfaces are also represented by the vortex rings. The wake of the ball is successfully simulated.
