The investigation of the velocity slip and the temperature jump effect on the heat transfer characteristics in a microchannel

Abstract

This paper presents a study of the influence of various factors on heat transfer in microchannels associated with the use of the velocity slip (including thermal creep) and temperature jump boundary conditions on the walls. These factors can affect heat transfer both individually and together, but their effect on heat transfer in the microchannel has still not been practically studied. An attempt to eliminate this lack was made in this paper. It was shown that as the slip length increases the value of the heat flux density increases by about 40% and the average heat transfer coefficient increases by about 50% compare to no-slip conditions. Wherein, the pressure drop significantly decreased, that is, two positive effects took place simultaneously. The presence of thermal creep also reduced the pressure drop in the channel and increased the average heat transfer coefficient, but this effect was significantly less than the effect of the slip length. On the other hand, the taking into account of a temperature jump on the wall led to a certain increase in the pressure drop, but the heat transfer coefficient increased.

Keywords

• Slip conditions
• Slip length
• Thermal creep
• Temperature jump
• CFD