Volume 13: Low Carbon Cities and Urban Energy Systems: Part II

Melting performance analysis of phase change material in latent heat storage unit with Y-shaped fins Zhan Liu, Zihui Liu, Xuqing Yang, Xiaohu Yang

Abstract

Latent heat storage (LHS) can improve the imbalance of energy supply and demand. However, the relatively low thermal conductivity of phase change materials (PCMs) may weaken the advantage of latent heat storage. In this paper, seven different fin combinations are designed for LHS device filling with paraffin wax RT56 as PCM. The fins are composed of straight and Y-shaped ones. For the same volume ratio of fins to PCMs, the width and height of fin are changed to study their effect on melting phase change. A 2D model is established and is solved numerically. Comparing of phase interface evolution verifies the established numerical model. Results show that the melting speed of PCM at the bottom of LHS device is slow, and the Y-shaped fin with longer part in the lower region for PCM can help heat penetrate into the interior of PCM, and promote the heat conduction inside the lower PCM, thus improving the overall melting performance. The PCM melting time of the unit with increasing fin height is shorter than that of the device with increasing fin width.

Keywords Latent heat storage; Phase change material; Y-shaped fin; Straight fin; Shell-and-tube heat exchanger