Computational analysis of the flow of pseudoplastic power-law fluids in a microchannel plate

Abstract

Abstract The flow of pseudoplastic power-law fluids with different flow indexes at a microchannel plate was studied using computational fluid dynamic simulation. The velocity distribution along the microchannel plate and especially in the microchannel slits, flow pattern along the outlet arc and the pressure drop through the whole of microchannel plate were investigated at different power-law flow indexes. The results showed that the velocity profile in the microchannel slits for low flow index fluids was similar to the plug flow and had uniform pattern. Also the power-law fluids with lower flow indexes had lower stagnation zones near the outlet of the microchannel plate. The pressure drop through the microchannel plate showed huge differences between the fluids. The most interesting result was that the pressure drops for power-law fluids were very smaller than that of Newtonian fluids. In addition, the heat transfer of the fluids through the microchannel with different channel numbers in a wide range of Reynolds number was investigated. For power-law fluid with flow index ( n = 0.4), the Nusselt number increases continuously as the number of channels increases. The results highlight the potential use of using pseudoplastic fluids in the microheat exchangers which can lower the pressure drop and increase the heat transfer efficiency.