Most accidents involving hydrogen begins with its leakage and spreading in the air and spontaneous detonation. In this study, the simulation of propagation of helium in a confined space with different methods of injection and ventilation of helium, which is used as a safe replacement of hydrogen in experimental studies. Five experiments were simulated in the range from laminar to developed turbulent with different Froude number, which determines the regime of the outflow of the helium in the air. The analysis of applicability of various turbulence models was conducted, which are used to close the system of equations of momentum transport. Comparison of the results of computational studies with experimental data showed good agreement. In particular, for transition and turbulent regime error of numerical results lies in the range from 5 to 15% for all turbulence models considered. This indicates applicability of the methods considered for hydrogen safety problems.