Heat Transfer Enhancement of a Low-Profile Block in a Channel Flow at Low Air-Velocity (original) (raw)

Abstract

investigation was preformed to enhance the heat transfer from a low-profile block placed in a channel flow at low duct Reynolds number of below 1000. The inflowing air to the heated block was accelerated due to the contraction effect by setting a barrier on the ceiling of the channel. The input electric-power to the cooling fan was kept constant, i.e., the flow rate decreases with increasing the pressure loss. The heat transfer from the heated block was dramatically increased in the conditions for which the flow reattachment on the top face of the block occurred as a result of the flow acceleration at the gap of the barrier. This method is particularly effective when the fan is operating at low loading conditions. If heated blocks are placed locally in a channel, the method using a barrier, which accelerates the flow directly around the blocks without increasing the flow rate, results in the less use of the fan power (pumping power) to achieve the heat transfer enhancement.

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Last updatedMarch 30, 2026