Combined Free and Forced Convection in Inclined Pipes with Buoyancy-aided and-opposed Flows

摘要

Combined free and forced laminar convection flow at Pe = 71 in the thermal entrance region have been studied numerically for isothermally heated and cooled inclined pipes. Numerical solutions including effects of inclination angle are obtained for velocity and temperature profiles, distributions of wall shear stress and the Nusselt number. The velocity and temperature profiles are distorted by combined effect of axial and cross-stream buoyancy. The circumferential average Nusselt number reaches the maximum at an inclination angle between 25° and 45° in the heating case but the maximum appears at 0° in the cooling case.