Effect of protrusion on thermal transient behavior of chips in a liquid channel during loss of pumping power

Experiments are performed to study the single-phase transient heat transfer at different protrusion heights of the electronic chips during an accidental stoppage of coolant flow due to loss of pumping power. Water is the coolant media and the flow covers the wide range of laminar flow regime with Reynolds number, based on heat source length, from 800 to 2625 and the heat flux ranging from 1 W/cm2 to 7 W/cm2. The general impacts of heat source protrusions (B=1, 2 mm) on heat transfer behavior of four chips are investigated by comparing the results obtained from flush-mounted (B=0) heat sources. Finally the correlation equations are obtained by modifying the correlations of flush-mounted heater, employing the chipsʹ protrusion height (B) in the dimensionless (B/ℓ) form.