Comparative effect of viscous dissipation on heat transfer in mixed convection flow: UWT and UHF cases

The effect of viscous dissipation on mixed convection flow about a rotating sphere with a prescribed uniform surface heat flux (UHF) has been investigated analytically. Merk's type of series expansions is used to obtain the heat transfer rate and the skin-friction coefficients. The results are presented for Pr=1;B=0, 1; ^*0, 0.5, 1 and various values of the dissipation parameter Ec^* at various angular positions. As in the case of uniform wall temperature (UWT), the heat transfer rate decreases with viscous dissipation. It is also observed that for an equivalence viscous dissipation effect, heating by UHF yields larger Nusselt number than heating by UWT.