Use of baffles for heat transfer reduction from a cylinder in cross flow

The problem of cross-flow forced heat transfer from a horizontal cylinder w ith multiple equally spaced low conductivity baffles on its outer surface w as investigated numerically. The effect of several combinations of baffles and baffle heights on the average Nusselt number was studied over a wide ra nge of Reynolds numbers. The results showed that there was an optimal numbe r of baffles for a minimum Nusselt number for a given value of baffle heigh t and Reynolds number. Short baffles slightly increased the Nusselt number at small Reynolds number values.