A theoretical study is presented in this paper to investigate the conjugate heat transfer across a vertical ®nite wall separating two forced and free convection ̄ows at different temperatures. It is assumed that the heat conduction in the wall is only in the transversal direction. We also assume that countercurrent boundary layers are formed on the both sides of the wall. The governing equation...

In this paper a transient free convection flow around a sphere with variable surface temperature and embedded in a porous medium has been considered. The temperature of the sphere is suddenly raised and subsequently maintained at values that varies with position on surface. The method of asymptotic expansions is applied for small Rayleigh numbers and then a finite-difference scheme is used to s...