Unsteady flow of gas at high pressure into a closed volume filled with liquid

Abstract

Within the framework of 2D (two-dimensional, axisymmetric) and 3D (three-dimensional) formulations of the problem, this article presents a numerical simulation of the process of gas outflow under pressure into a closed container partially filled with liquid. The authors have performed the numerical modeling using the open platform OpenFOAM with the help of a solver based on the method of liquid volumes (VOF method) with a standard k-e turbulence model. A comparison is made with the one-dimensional (1D) asymptotic model, in which the oscillations of the fluid as a whole are determined by the enthalpy balance. A numerical study of the evolution of pressure during gas outflow is carried out. The results show that the physical properties of the fluid used affect the amplitude and frequency of the pulsations. The modeling has shown that gas flows into water in the form of a jet, and a projectile forms in liquid lead near the hole through which it flows out. The significant influence of three-dimensional effects on the evolution of gas outflow into liquid is demonstrated. Satisfactory agreement was obtained for both two-dimensional and three-dimensional calculations and the results obtained using the asymptotic model. For the “gas — water” system, the results of calculations by the asymptotic model give a significant difference from the results of numerical calculations.