Heat Storage Characteristics Analysis and Structural Parameter Optimization of Phase Change Heat Storage Unit Based on Sine Function Pipe

Abstract

The phase-change heat storage unit filled with paraffin is used as the research object. Aiming at the low thermal conductivity of phase change materials, we propose a structured pipeline based on sine function to improve the melting performance of the latent heat storage system. We used a heat storage performance test system and a numerical simulation method to simulate the phase change heat transfer process. We studied the effect of the sine function structure and Reynolds number on the enhanced heat transfer characteristics of the unit without the design of the fins.The results show that the combined action mechanism of sinusoidal pipe structure and local heat transfer of phase change material can significantly shorten the heat charge time, and the melting rate increases first and then decreases. Reducing the wavy period and adjusting the peak height can shorten the heat charging time, but reduce the heat storage; Based on the analysis of heat charging time, heat storage and average heat flux density, we found that the pipelines with the best influence on the comprehensive performance of convective heat transfer of sinusoidal pipelines are those with ripple period between 100mm-150mm and wave peak height around 15mm through single factor optimization.