Experimental study on heat transfer and friction in pin fin channel flow

Experimental work is conducted to examine the effect of porosity, originated from the theory of the porous medium flow, on both the heat transfer rate and friction behavior for flow through a pin fin channel. Four units of the pin fin matrix having different porosities are used in the flow test. The heat transfer rates are obtained using the LMTD method. It is found that the hear transfer rate is higher for flow through a high porosity pin fin matrix, which possesses a higher heating surface area. For a relatively large Reynolds number flow, the friction factors are found to depend only on the flow porosity due to the presence of the roughness-like pin fin protruding through the viscous sublayer. Average friction factors are then suggested for every pin fin channel.