Calculation of the speed descrioptions of the upward swirling gas flow in conditions of lateral wind action

Abstract

The paper presents the results of numerical simulation of lateral wind impact on three-dimensional non-stationary air flows in ascending vortex flow of artificially created tornado in the stationary operating mode. The mathematical model represents a complete system of Navier-Stokes equations taking into account the viscosity and thermal conductivity of the moving gas, as well as the effects of gravity and Coriolis. Using the explicit difference scheme and the corresponding choice of initial and boundary conditions, the solutions of the complete system of Navier-Stokes equations in the computational domain representing a rectangular parallelepiped are numerically obtained. All components of gas flow speed are calculated at fixed time points and instantaneous current lines are built taking into account the constant horizontal wind speed. The calculations showed that the result of the wind action on the ascending vortex flow is an unsymmetrical change in the circumferential velocity, its uneven deformation at opposite sections, and the total displacement of the vortex in the wind direction. Besides, the displacement and the curvature of the vertical vortex part in wind direction are established, the “separation” of some instantaneous current lines from vertical rotating part and the area in the vortex center increasing in diameter, free from current lines is fixed. In the studied time change range, the wind resistance of the air vortex and stable operation of the used computational scheme are observed.