Release:
2024. Vol. 10. № 3 (39)About the authors:
Pavel I. Tomchik, Postgraduate Student, Department of Fundamental Mathematics and Mechanics, School of Computer Sciences, University of Tyumen, Tyumen, Russia; p.i.tomchik@utmn.ru, https://orcid.org/0000-0001-6960-4097Abstract:
Studying the stability of natural convection remains relevant in many areas of modern science: astrophysics, meteorology, thermal physics, nuclear power engineering, and machine learning, among others. One of such research areas is numerical modeling of convection during the changes in the flow regime of a liquid or gas. The article presents a detailed modeling of single- and double-vortex flow regimes of an incompressible fluid in a square region divided by a computational grid with an even and odd number of nodes. Transitions between these flow regimes are modeled when a disturbance is introduced into certain grid nodes. At start, the fluid is at rest; over time, during the heat transfer from the hot side of the square region, natural convection of the fluid begins, which forms under of one or more vortices of a laminar flow under certain conditions. The study has shown that as for the mechanical stability, the effect of the transition from a double-vortex to a single-vortex flow was observed when a disturbance source in the form of a multiple increase in temperature was introduced at the start. The authors have used a mathematical model of natural convection in the Boussinesq approximation; the calculations were performed until a steady-state flow regime was reached. The modeling results obtained for computational grids 20 × 20 and 21 × 21 control volumes are presented on graphs as pressure and temperature fields, velocity projections on coordinate axes, and streamline images.Keywords:
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