We have performed three-dimensional numerical simulations of accretion discs in a close binary system using the Smoothed Particle Hydrodynamics ( SPH ) method .
Our results show that , contrary to previous claims , 3D discs do exist even when the specific heat ratio of the gas is as large as \gamma = 1.2 .
Although the disc is clearly more spread in the z -direction in this case than it is for the quasi-isothermal one , the disc height is compatible with the hydrostatic balance equation .

Our numerical simulations with \gamma = 1.2 also demonstrate that spiral shocks exist in 3D discs .
These results therefore confirm previous 2D simulations .