NATURAL CONVECTION HEAT TRANSFER FROM STAGGERED DISCRETE THERMAL SOURCES: STATE-OF-THE-ART

ABSTRACT. The enhancement technique for natural convection systems based on staggering vertical thermal sources has been reviewed and discussed. The potential for the heat transfer enhancement of an array of staggered, discrete, vertical surfaces is ascribed to the systematic interruption of the boundary layer caused by the short length of the discrete sources. Considering a system of uniformly heated vertical surfaces as a reference, the use of staggered, discrete surfaces gives rise to higher average heat transfer coefficients. This enhancement strategy has been adopted to increase the natural convection heat transfer from vertical channels as well as from arrays of vertical surfaces. Main applications include the thermal control of electronic equipment, solar system devices and the design of heat sink and/or heat exchanger. The most significant results presented in relevant papers are discussed and compared for the purpose of drawing the guidelines for the optimal design of such advanced thermal systems.