NATURAL-CONVECTION HEAT-TRANSFER IN STAGGERED VERTICAL CHANNELS

Numerical solutions are obtained for both discrete plate array and par allel plate arrays by solving mass, momentum and energy equations, to determine whether a staggered array of discrete vertical plates yields an enhancement in heat transfer as compared to an array of continuous parallel vertical plates in natural convection. The comparison is mad e for an equal heat transfer surface area in both cases. It is found t hat the use of discrete plates gives rise to enhancement in heat trans fer when the parameter (D(h)/H)Ra > 600; it is also found that the ext ent of enhancement is increased at high heat fluxes, larger transverse spacings and for numerous shorter plates. It is also found that the e nhancement is restricted to only low system heights, vertical channels giving higher heat transfer rates at larger heights. For the paramete r ranges investigated, the heat transfer, relative to the parallel pla te array is enhanced by a factor of 3.