Experimental Validation of Thermal Performance of a Plate Heat Exchanger (PHX) with Phase Change Materials (PCM) for Thermal Energy Storage (TES)

Abstract

Thermal energy storage (TES) platforms can help to improve the energy efficiency of various types of thermal management systems by actively modulating the transient response of these integrated thermal systems. A novel strategy for TES platforms involve the integration of Phase Change Materials (PCM) into various types of heat exchangers (HX). High performance, compact, and low cost HX platforms for TES involving PCM are often desired for applications such as power plants, edifice thermal management, transportation technologies (e.g., aerospace and automotive vehicles), and high heat flux electronics cooling. These applications are often constrained by requirements for minimizing pressure loss, miniaturizing the form factors, and the need for easy scalability to large systems. This imposes steep challenges for design, fabrication, and operation of these HX platforms. This also severely restricts the available options and material choices for PCM. In this experimental study, the transient performance of a Plate Heat Exchanger (PHX) integrated with PCM were analyzed for realizing a Latent Heat Storage Unit (LHSU). This study enabled a detailed experimental characterization of the efficacy of the LHSU realized in a PHX (model: SWEP B5T). The inner volume of the PHX was filled up with PCM. The PCM considered was PureTemp 29 with a phase transition temperature of 29 °C. The temperature of the Heat Transfer Fluid (HTF) was varied from 32°C - 38°C for melting and 20°C - 26°C for solidification. The HTF used in this study was water. The volumetric flow-rate ranged from 5, 7.5 and 10 GPH. Experimental validation for the transient response of the LHSU (i.e. the charging and discharging time periods) were performed by parametrically varying the design and operational conditions, which include: flow rate, fluid inlet and exit temperatures, and the energy storage capacity.