Experiments on chimney-enhanced free convection

Experimental results are presented for thermal systems consisting of a vertical, parallel-plate, isothermal heat sink and a chimney. A ridge of maximum total hear transfer is observed with respect ro 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.