Study On The Heat Storage And Heat Release By Paraffin Phase Change Outside The Pipe

Energy, environment and energy saving have already been the world's urgent and important work. New and renewable energy should be used to reduce conventional energy's consumption. The short-term or long-term energy stored technique would be suitable method to supply and reuse energy. Due to the merits of high-density energy storage, easy to match and easy to control, the research and application of Phase Change Thermal Energy Storage (PCTES) technique has drawn more attention. This paper will research the heat transfer process of paraffin phase change in theoretical and experimental aspects.The mathematical models and methods of phase change heat transfer were studied. And a simplified heat transfer mathematical model of pipe outside phase change was researched in this paper.Experimental study on paraffin melting process's law of phase change outside pipe was carried out in different locations and the impact of natural convection to melting process was analysed. The optimal melting time and paraffin thickness have been gained. Different impacts caused by different water temperature and flow to paraffin melting were researched. Contrast on different impacts to paraffin melting process between one heat source and two heat sources.In heat release experiment, the paraffin solidification law of phase change outside pipe was carried out in different locations and the impact of natural convection to solidification was analysed. By contrasting on the impacts of different water temperature, a critical temperature different activating natural convection has been gained. Comparing with one cold source, two cold sources would cause different effects to solidification.