ABSTRACT
The periodic natural convection in an inclined square enclosure is studied numerically. One of the cavity sides is maintained at a constant temperature, and the temperature of the opposite wall is varied by the sine law. The mean value of this temperature in a period was lower than the given constant temperature. The other two walls of the enclosure were adiabatic. The system of Navier–Stokes Equations in Boussinesq approximation is solved numerically by the control-volume method with the SIMPLER algorithm. Solutions are obtained for Grashof number equal to 5 × 105 and Prandtl number equal to unity in a wide range of oscillation frequency variation. The heat transfer dependency on oscillation frequency is studied for different values of inclination angle. It is found that there is a possibility of heat transferring from the colder wall to the hotter one in the whole range of problem parameters. The possible causes of such a phenomenon are analyzed.
A preliminary version of this article was presented at CHT-04: An ICHMT International Symposium on Advances in Computational Heat Transfer, April 2004, G. de Vahl Davis and E. Leonardi (eds.), CD-ROM Proceedings, ISBN 1-5670-174-2, Begell House, New York, 2004.