Experimental results are presented for thermal systems consisting of a vertical, parallel-plate, isothermal heat sink and a chimney. A ridge of maximum total heat transfer is observed with respect to the plate spacing and heat-sink height. The magnitude of heat transfer and the location of optima confirm prior theoretical predictions by Fisher et al (1997) to within 11 percent. Averaged velocity measurements closely match theoretical predictions of mean velocity. Cold inflow at the chimney exit is quantified and shown to decrease overall heat transfer by approximately four percent.

Issue Section:
Natural and Mixed Convection
Keywords:
Channel, Enhancement, Heat Transfer, Natural Convection
Topics:
Heat transfer, Natural convection, Heat sinks, Inflow, Thermal systems, Velocity measurement
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