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SUMMARYA numerical algorithm to study the boundary-value problem in which the governing equations are the steady Euler equations and the vorticity is given on the in ow parts of the domain boundary is developed. The Euler equations are implemented in terms of the stream function and vorticity. An irregular physical domain is transformed into a rectangle in the computational domain and the Euler equations are rewritten with respect to a curvilinear co-ordinate system. The convergence of the ÿnite-di erence equations to the exact solution is shown experimentally for the test problems by comparing the computational results with the exact solutions on the sequence of grids. To ÿnd the pressure from the known vorticity and stream function, the Euler equations are utilized in the Gromeka-Lamb form. The numerical algorithm is illustrated with several examples of steady ow through a two-dimensional channel with curved walls. The analysis of calculations shows strong dependence of the pressure ÿeld on the vorticity given at the in ow parts of the boundary. Plots of the ow structure and isobars, for di erent geometries of channel and for di erent values of vorticity on entrance, are also presented.

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To describe the far turbulent wake flow behind a towed body in a linearly stratified medium we use an hierarchy of semi-empirical turbulent models. The most complex model comprises differential equations for transport of normal Reynolds stresses. We give computational results demonstrating far turbulent wake dynamics both in a passively and actively stratified medium as compared to far momentumless turbulent wake dynamics. We numerically simulate the anisotropic decay of turbulence in a far wake behind a towed body. We give computational results of turbulent wake characteristics for large decay periods.