Performance investigation of multi-stage hydrogen-based sorption heat pump

Abstract

Metal hydrides are broadly investigated, for more than three decades, towards its application for cooling and heating applications. As a continuation of those works, in the present study, authors have investigated the performance of a multi-stage sorption heat pump for multiple cooling and heating outputs. The metal hydrides selected for the present study are Ti0.98Zr0.02V0.43Fe0.09Cr0.05Mn1.5, MmNi4.7Al0.3, LaNi4.8Al0.2 and Zr0.9Ti0.1 Cr0.9Fe1.1, with the operating temperature range as 20°C for cooling output, 45°C for heating output and 140°C for heat supply. The system produces three cooling and four heating outputs with only one heat input. The performance of the system is investigated, via finite volume approach, in terms of hydrogen interaction within the coupled beds, bed temperature variations and heat interactions during hydrogen transfer processes. The minimum temperature observed during the cooling process is 0.5°C, whereas the maximum temperature observed during the heating process is 60°C, which shows that the obtained temperature is capable of space air-conditioning. On the other hand, the maximum cooling and heating outputs, at a particular instant of time, are estimated at 361 W and 402 W, respectively with a heat supply of 23 W.