Because of technological restrictions, it is actually impossible to fabricate smooth microchannels. Therefore, exploring the roughness effects on the flow characteristics at microscale is of great importance for scientific communities.Thepresentinvestigationdealswiththeeffectsofcorrugatedroughnessonthefullydevelopedslipflow forced convection in micropipes. The governing equations subject to first-order slip boundary conditions are solved by means of the straightforward perturbation method. Closed-form expressions are obtained for the dimensionless velocity and temperature distributions, for the friction coefficient and pressure drop, and finally for the Nusselt number. The results demonstrate that the corrugated roughness increases both the pressure drop and the heat transfer rate, with the amount of the increase in the pressure drop being a little more. Despite increasing the heat transfer rate, the effect of roughness is found to be unfavorable as it leads to smaller values of the channel performance, defined as the ratio of the heat transfer rate to the pressure drop. In other words, for a given heat transfer rate some increase in pumping power requirements is incurred.
