Comparison of 2d and 3d Models of Flow Structure in Semidetached Binaries

We present the results of systematic comparison of 2D and 3D numerical models of mass transfer in semidetached binaries. It is shown that only for case of $\gamma$ 1 (near-isothermal case) the obtained 2D and 3D solutions are qualitatively similar. For higher value of $\gamma$ the 3D flow structure is drastically changed and for $\gamma$=1.2 the accretion disk is not formed in the system. Numerical results show that for case of $\gamma$=1.2 the 2D and 3D solutions are different. We discuss the spiral-shaped shock waves obtained in numerical models. It is shown that these shocks are not intrinsic spirals and are caused by collisions of the gaseous flows in the system.