Modeling of Natural Thermogravitational Convection in Horizontal Channels with an Irregularly Shaped Cross Section

Results of a numerical investigation of the natural thermogravitational convection of air in horizontal channels with a shaped cross section are presented. Twodimensional unsteady equations of convection in the Boussinesq approximation, which are written in the velocity vortex–current function–excess temperature variables, are employed as a mathematical model. In investigating, the range of Rayleigh numbers was bounded above by the value 10⁶, which corresponds to the range of applicability of the Boussinesq approximation to air in the problem posed. The boundaryvalue problem was solved numerically by the finiteelement method of Galerkin (weak formulation). The distinctive features of the temperature and flow fields were revealed on the basis of calculations and the intensity of heat exchange was evaluated.