ABSTRACT
This paper presents experimental investigation of the effect of number of layers as
well as the flow arrangement on the performance of a microchannel heat sink system
(MCHS). The effect of flow rate on pressure drop, temperature uniformity, and outlet
temperature in single and double layers MCHS under the effect of uniform heat flux
condition was investigated. The MCHS used had micro channels with rectangular
cross section. The heat flux applied during the experiments was varied from 5.0 to
13.68 W/cm2. The results of single layer MCHS were compared with theoretical
predictions in order to validate the results of the present test rig. From the obtained
results it was observable that the outlet temperature was highly dependent on the
mass flow rate until a certain value after which change in the outlet temperature was
minor. On the other hand, the pressure drop increased almost linearly with the
increase in mass flow rate due to laminar nature of the flow. When multilayer
systems were tested, the main observation was a significant reduction in the
pressure drop compared to the single layer case for the same mass flow rate.
Moreover, flow arrangement was found to have an impact on pressure drop which
was smaller in the case of counter flow arrangement compared to parallel flow
arrangement case. Flow configuration (parallel, counter, or cross-flow) had a
significant effect on temperature uniformity over the heat sink area with counter-flow
arrangement giving best temperature uniformity followed by the cross-flow
arrangement. Change in the outlet temperature in the case of multilayer and single
layer systems was not significate which may be due to the fact that the same mass
flow rate was applied to all tested cases.