Performance and life cycle assessment of pillow plate heat exchanger utilizing microencapsulated phase change material slurry

Abstract

The pillow plate heat exchanger is a promising and relatively new heat exchanger design that enhances heat transfer by augmenting flow turbulence. This study focuses on further enhancing the heat exchanger’s performance by utilizing Microencapsulated Phase Change Material (MPCM) slurry which increases the heat capacity of the working fluid. So, the heat transfer characteristics, flow performance, and life cycle assessment of the pillow plate heat exchanger when employing MPCM slurry with varying particle concentrations are evaluated. The investigation takes into account the intricate phenomenon of conjugate heat transfer between channels, enabling a comprehensive analysis of the system's behaviour. To avoid modelling errors, a lab-scale heat exchanger is simulated instead of using periodic boundary conditions to capture the effects of both developing and fully developed regions. The results showed that temperature distribution in the heat exchanger is highly affected by developing regions in both inner and outer channels. Meanwhile, by adding MPCM, a better cooling performance with a lower temperature variation in cold temperatures is provided at the cost of a higher pressure drop. However, 6.2% enhancement in the heat transfer rate is achieved by using a 15% MPCM concentration which is a considerable amount in thermal management systems in industries requiring efficient heat dissipation, such as electronics cooling. The Life Cycle Assessment indicated that although there is a slight increment in emissions as the concentration of MPCM increases, the overall impact is minimal on the environment.