ANALYSIS AND OPTIMIZATION OFF A NATURAL DRAFT HEAT SINK SYSTEM

An analytical solution for a system consisting of a vertical, parallel -plate, isothermal heat sink, and a chimney is presented, The result i s applied to problems in which the size of the overall system is const rained, A ridge of maximum total heat transfer is observed with respec t to the plate spacing and heat-sink height, The ridge suggests that h eat-sink height may be reduced without diminishing the thermal perform ance for natural draft cooling, The how characteristics of optimal sys tems reveal that systems with and without chimneys dissipate maximum h eat when the velocity profiles within the heat sink are fully develope d and developing, respectively.