An analysis for heat transfer in micro-annular channel with unsymmetrically heated walls in slip flow regime

摘要

A theoretical analysis is processed for flow and heat transfer in micro-annular channel under unsymmetrical wall heat flux in slip flow regime. The momentum and energy equations with the boundary conditions of slip velocity and temperature jump are solved for the fully developed laminar flow and heat transfer of incompressible gas in this microchannel. It was found that the average drag friction coefficient and both the Nusselt number ratios for two unsymmetrically heated walls decrease with the Kn number increasing. Besides, the ratio of inner diameter to outer diameter, r{sup}*, has little influence on the average drag friction coefficient ratio, and has a contrast influence on the Nusselt number ratio for inner wall or for outer wall at a fixed heat flux ratio. Similarly, the heat flux ratio also has a contrast influence on these Nusselt number ratios at the same r{sup}*.