Heat transfer in microtubes with viscous dissipation

Convective heat transfer for steady state, laminar, hydrodynamically develo ped flow in microtubes with uniform temperature and uniform heat nux bounda ry conditions are solved by the integral transform technique. Temperature j ump condition at the wall and viscous heating within the medium are include d. The solution method is verified for the cases where viscous heating is n eglected. For uniform temperature case, with a given Brinkman number, at sp ecified axial lengths, the viscous effects are presented for the developing range, reaching the fully developed Nusselt number. The effect of viscous heating is investigated for both of the cases where the fluid is being heat ed or cooled. Prandtl number analysis has shown that, as we increase the Pr andtl number the temperature jump effect diminishes which gives a rise to t he Nusselt number. (C) 2001 Published by Elsevier Science Ltd.