Basic Research on the Latent Heat Thermal Energy Storage Utilizing the Contact Melting Phenomena

Abstract

A latent heat thermal energy storage capsule, having a horizontal heat transfer surface at the bottom and storing the energy by contact melting, is prepared. The time-dependency of the storage heat flux is measured, using n-octadecane as the phase change material. Next, the non-dimensional formula for the contact melting heat flux in the steady state is derived, based on the results of the previous papers. Using the above formula, the time-dependency of the heat flux in the storage process is analyzed generally and the approximate solution is shown to agree well with the experimental results. Then, the effects of the PCM properties and the capsule specifications on the average heat flux are summarized.