Constructal flow orientation in conjugate cooling channels with internal heat generation

摘要

This paper presents the development of the three-dimensional flow architecture of conjugate coolingchannels in forced convection with internal heat generation within the solid for an array of circular coolingchannels with different flow orientation. Three flow orientations were studied: array of channels withparallel flow; array of channels in which the flow in every second row is in a counter direction with itsneighbours, and flows in all the arrays of channels are in counter flow relative to each other. The geometricconfigurations were determined in such a way that the peak temperature was minimised subject tothe constraint of fixed global volume of solid material. The degrees of freedom of the design were hydraulicdiameter and channel to channel spacing. A gradient-based optimisation algorithm was applied tosearch for the best optimal geometric configurations that improve thermal performance by minimisingthermal resistance for a wide range of dimensionless pressure differences. The effect of porosities, appliedpressure difference, flow orientation and heat generation rate on the optimal hydraulic diameter andchannel to channel spacing is reported. The results show that the effects of dimensionless pressure dropon minimum thermal resistance were consistent with those obtained in the open literature.