1. water and air are separated by a plane wall. it is proposed to increase the heat transfer rate by adding adding straight rectangular fins to the wall. the fins have 1.27 mm thickness and 3.0 cm length. the fins are spaced 1.27 cm apart from each other. the air-side and water-side heat transfer coefficients are assumed constant and have the values 11.4 w/(m2 k) and 256 w/(m2 k), respectively. the thermal conductivity of the fins is 42.9 w/(m k). you may assume the steel wall is so thin that any resistance to conduction it produces is negligible. determine the percent change in total heat transfer when the fins are placed on (i) the water side, (ii) the air side, and (iii) both sides. briefly explain why it is more effective to have the fins on the air side.
