Experimental and numerical study on the performance of a minichannel heat sink with different header geometries using nanofluids

Abstract

Inefficient distributor and collector header design in a minichannel heat sink causes flow maldistribution which can severely degrade the thermal and hydraulic performance of the heat sink. This paper presents an experimental and numerical investigation on the thermohydraulic performance of minichannel heat sinks with two different header geometries using nanofluids. A series of tests are conducted on a minichannel heat sink with optimized and conventional header geometries by using (Al2O3-H2O) nanofluids and distilled water as coolants. The effects of header geometry, nanoparticle concentration, and coolant flow rate on the overall heat transfer coefficient, heat transfer enhancement, thermal resistance, and base temperature are investigated. The experimental and numerical results exhibited good agreement, indicating that the thermohydraulic performance of the heat sink with the optimized header geometry is superior to that with the conventional header geometry. The minichannel heat sink with the optimized header geometry exhibited 17% higher overall heat transfer coefficient and 43% reduction in pressure drop while achieving lower values for base temperature and thermal resistance for each employed flow rate and volumetric concentration of nanoparticles. Furthermore, the performance evaluation criteria (PEC) indicated a 41% improvement in hydraulic performance while using minichannel heat sink with optimized header geometry compared to that with the conventional header geometry.