Parametric study of flat plate solar collectors

Abstract An analytical program, suitable for use on a digital computer is developed for the purpose of studying the hourly behavior of a flat plate solar collector. The influence of a large variety of collector parameters over the period of a year are shown in the plotted results. The solar energy that arrives at the collector is based on average conditions for the State of Rhode Island. Weather Bureau records and Eppley Laboratory data for the past ten years were studied to determine the ambient temperature, average diffuse radiation on clear days, average cloudiness, and influence of cloudiness on total radiation. These quantities were then put in the form of empirical equations so that they would predict the proper input for a computer program. The results indicate that the energy absorbed by a collector and its daily efficiency are strongly dependent on collector temperature and cloudiness. One must be very careful not to report a collector efficiency without giving the conditions under which a collector operates and the collector geometry. The results presented in this paper show the influence of cloudiness, collector temperature, number of covers, wind velocity, air space heat transfer coefficient, coolant heat transfer coefficient, tube spacing, azimuth angle and slope of surface, and plate absorptivity on collector performance.