  Results of numerical simulations of the impact of a common envelope on the
matter flow pattern near the outflowing component in a semidetached binary
system are presented. Three-dimensional modeling of the matter transfer gas
dynamics in a low-mass X-ray binary X1822-371 enable investigation of the
structure of flows in the vicinity of the inner Lagrange point L1. Taking into
account the common envelope of the system substantially changes the flow
pattern near the Roche surface of the outflowing component. In a stationary
regime, accretion of common envelope gas is observed over a significant
fraction of the donor star's surface, which inhibits the flow of gas along the
Roche surface to L1. The change in the flow pattern is particularly significant
near L1, where the stream of common envelope gas strips matter off the stellar
surface. This, in turn, significantly increases (by an order of magnitude) the
gas flow from the donor surface in comparison with the estimates of standard
models.
