Flow characteristics and heat transfer performance of half-corrugated microchannels

Abstract

The single-phase pressure drop and heat transfer performance of half-corrugated microchannels under a low Reynolds number (<900) are studied via three-dimensional numerical simulation and experiment. Comparative studies between half-corrugated and flat-bottom copper microchannels are analyzed to access the pressure drop and thermal performance enhancement. Compared with flat bottom microchannels, the half-corrugated mirochannels have a significant pressure drop diminution at a given Reynolds number. The wave length of the half-corrugated microchannels has a strong impact on the pressure drop, and the effect of wave amplitude can be neglected at a Reynolds number of 153–814 (flow speed of 0.2–1.2m/s). In addition, the heat transfer performance for half-corrugated microchannels is enhanced when the effective heat flux is beyond 150kWm−2. The flow behaviors of the microchannels with different half-corrugated structures are obtained from three-dimensional numerical simulations and are applied to explain the enhanced heat transfer and lower pressure drop. Moreover, a new parameter, the relative thermal-hydraulic performance index G, is defined to evaluate the overall performance of the half-corrugated microchannels. Compared with double sinusoidal corrugated microchannels, the half-corrugated microchannels possess excellent overall performance.