MODELING OF NATURAL THERMOGRAVITATIONAL CONVECTION IN HORIZONTAL CHANNELS WITH AN IRREGULARLY SHAPED CROSS SECTIONI. A. Ermolaev, A. I. Zhbanov, and V. S. Koshelev UDC 536.24:532.54 Results of a numerical investigation of the natural thermogravitational convection of air in horizontal channels with a -shaped cross section are presented. Two-dimensional 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 boundary-value problem was solved numerically by the finite-element 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. N. G. Chernyshevskii Saratov State University, Saratov, Russia; email: ZhbanovAI@info.sgu.ru. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 76, No. 4, pp. 134-137, July-August, 2003. Original article submitted November 1, 2002.