VORTICITY DISTRIBUTION CAUSED BY 3-DIMENSIONAL DISTURBANCE IN 2-DIMENSIONAL SHEAR-FLOW

The vorticity distribution in a two-dimensional shear flow around a so urce doublet on a plane is investigated analytically with an incompres sible inviscid fluid. The velocity field is obtained by the linearized Euler equation. With this velocity field the inertial turning of a vo rtex line which is straight far upstream is investigated by use of the Lagrangian method, and the vorticity distribution downstream of the d oublet is obtained. It is shown that there remains a finite vorticity far downstream of the doublet where the disturbances vanish in the lin earized approximation.