Effect of radiator position and mass flux on the dryer room heat transfer rate

Abstract

A room radiator as usually used in cold countries, is actually able to be used as a heat source to dry goods, especially in the rainy season where the sun seldom shines due to much rain and cloud. Experiments to investigate effects of radiator position and mass flux on heat transfer rate were performed. This study is to determine the best position of the radiator and the optimum mass flux. The radiator used was a finned radiator made of copper pipes and aluminum fins with an overall dimension of 220mm×50mm×310mm. The prototype room was constructed using plywood and wood frame with an overall size of 1000mm×1000mm×1000mm. The working fluid was heated water flowing inside the radiator and air circulating naturally inside the prototype room. The nominal mass fluxes employed were 800, 900 and 1000kg/m2s. The water was kept at 80°C at the radiator entrance, while the initial air temperature inside the prototype room was 30°C. Three positions of the radiator were examined. The results show that the effect of the mass flux on the forced and free convection heat transfer rate is insignificant but the radiator position strongly affects the heat transfer rate for both forced and free convection.