Heat transfer in a twin-blow narrow channel with two opposite walls roughened by skewed ribs arranged in staggered manner

Abstract

This experimental study performs the detailed heat transfer measurements over a skewed-rib roughened surface in a rectangular narrow channel with two equal-area flow entrances located on two adjacent edges of a channel-corner. This flow configuration allows for increasing the coolant-flow fed into the narrow channel without increasing the height of assembly in order to enhance the capacity of cooling duty for electronic chipsets. At a specified total coolant mass flow rate, four test scenarios, namely the single-blow from the side or upper entrance and the twin-blow with the coolant mass flow ratio of 1 : 1 or 2 : 1 between the side and upper blows are performed. A selection of full-field heat transfer distributions over the rib-roughened surface illustrates the manner by which the flow entry condition and the Reynolds number affect the local and spatially averaged heat transfers. With fixed total coolant consumptions, the twin-blow with the coolant mass flow ratio of 2 : 1 between the side and upper blows elevates the spatially averaged heat transfers to the levels of 150–180% of the single-blow references. A regression-type analysis is subsequently performed to develop the correlation of spatially-averaged Nusselt numbers over rib-roughened surface, which permits the effect of Reynolds number on heat transfer to be determined for four test scenarios.