Release:
2018, Vol. 4. №1About the authors:
Roman E. Volkov, Postgraduate Student, Department Algebra and Mathematical Logic, University of Tyumen; email@romanvolkov.ruAbstract:
This paper, using numerical experiments, aims to establish the nature of the changes in the speed and energy characteristics of the swirling air flow that forms when it leaves the stationary mode, and with a sudden step-like decrease in the vertical blowing speed.
The authors use the complete system of Navier-Stokes equations to describe complex non-stationary three-dimensional flows of a compressible viscous heat-conducting gas. This system of nonlinear equations is a differential form of recording the basic laws of conservation of mass, momentum, and energy. In addition, it takes into account the laws of thermodynamics and the action of gravity and Coriolis.
In the case of constant values of the coefficients of viscosity and thermal conductivity, functions that determine the exact solution of the complete system of Navier-Stokes equations are taken as initial conditions for describing the corresponding flows of a compressible viscous heat-conducting gas.
For the density on all six faces of the calculated parallelepiped, the condition of continuity of the flow is stated. The boundary conditions for the components of the gas velocity vector correspond to the non-flow conditions for the normal component of the velocity vector, and the symmetry conditions for the other two components of the velocity vector. For the temperature on all six faces, the conditions for thermal insulation are specified.
The numerical solution of the complete system of Navier-Stokes equations made it possible to establish the nature of the change in the velocity and energy characteristics of the ascending swirling airflow initiated by a vertical blow through a pipe 5 meters in diameter when it leaves the stationary regime. The results of numerical simulation of a smooth transition to a stationary mode of a lower energy level are given with a stepwise decrease in the velocity of a vertical purge as well as a complete stoppage of the vortex flow.
The results of the calculations allow us to give meaningful recommendations for a large-scale full-scale experiment on creating an artificial tornado.
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