Experimental Investigations on Latent Heat Storage Unit using Paraffin Wax as Phase Change Material

TLDR

The study examines a shell‑and‑tube latent heat storage unit that uses paraffin wax (58–60 °C melting point) as the phase change material. The study experimentally evaluates the thermal performance of the latent heat storage unit. The authors measured temperature evolution in the paraffin and varied the heat‑transfer‑fluid mass flow rate (0.0167–0.0833 kg s⁻¹) and inlet temperature (75–85 °C) to assess their effects on melting and solidification heat fractions. Results show that lower mass flow rates and inlet temperatures lengthen the melting time, and that inlet temperature has a greater impact on heat fraction than flow rate during melting.

Abstract

Thermal performance of a latent heat storage unit is evaluated experimentally. The latent heat thermal energy storage system analyzed in this work is a shell-and-tube type of heat exchanger using paraffin wax (melting point between 58°C and 60°C) as the phase change material. The temperature distribution in the phase change material is measured with time. The influence of mass flow rate and inlet temperature of the heat transfer fluid on heat fraction is examined for both the melting and solidification processes. The mass flow rate of heat transfer fluid (water) is varied in the range of 0.0167 kg/s to 0.0833 kg/s (1 kg/min to 5 kg/min), and the fluid inlet temperature is varied between 75°C and 85°C. The experimental results indicate that the total melting time of the phase change material increases as the mass flow rate and inlet temperature of heat transfer fluid decrease. The fluid inlet temperature influences the heat fraction considerably as compared to the mass flow rate of heat transfer fluid during the melting process of the phase change material.