Analytical and experimental study of a forced-convection type nocturnal radiator

An analytical model is developed to predict the nocturnal thermal performance of a forced-convection type nonselective radiator: its validity is examined by comparison of the predictions with the results of several outdoor experiments. In the experiments, the Reynolds number of a working fluid, which is water in the present study, is varied, while the inlet fluid temperature is kept constant. The presented model predicts time variations in the exit fluid temperature of the radiator accurately.