Experimental Study on the Properties of Phase-Change Solar Thermal Stores

A study of the function performance of paraffin material in phase change thermal storing was presented. An experimental device was set up for the performance tests of the concentric tube-type phase-change heat store and for the investigation of the phase transition temperature field changing over time under constant temperature condition. Comparisons were carried out between the effects of changing the inlet temperature and flow rate of heat transfer fluid on the storing time, and between the changes of temperature at different points under the same thermal and fluid conditions inside the store. Furthermore, the design of the experimental bench was enlarged, according to the similar criteria theory, for application to the split solar water heating systems. The results showed that the effect of the inlet temperature of heat transfer fluid on the storing time was greater than that of the flow rate, and that the solar hot water systems with phase change thermal storage can enhance the shower capacity from 13 people to 17 people.