Experimental evaluation of a simulation model for wrap-around heat exchanger, solar storage tanks

摘要

The thermal performance of a commercially available 80 gallon, solar storage tank with an integral wrap-around heat exchanger is characterized experimentally an indoor test stand. The experimental results are used to evaluated the accuracy of a previously developed simulation model. Heat input on the collector side of the heat exchanger is held constant causing the heat transfer to reach a quasi-steady state. Temperatures in the heat exchanger and tank increase with time, however, the temperature differences across the heat exchanger remain nearly constant. Several combinations of heat input and collector loop flow are investigated. The development of the tank temperature profiles over time and the overall heat transfer performance predicted by the model are compared with experimental results. The influence of an electric auxiliary heater located in the top of the solar storage tank on the heat exchanger performance is investigated. Experimental normalization of the model is considered and modifications to the model and experiments are recommended.