Performance analysis to metal hydride heat pumps for temperature upgrading

The formulae for calculating coefficients of performance (COP) of metal hydride heat pumps (MHHP) for temperature upgrading are proposed after considering practical factors such as heat transfer of metal hydride bed and sensible heat exchange, which provide a theoretical basis for reasonably selecting metal hydrides pair and adjusting diversified process parameters of MHHP. The simulation results show that the effective measures to improve COP of MHHP include enhancing heat transfer in metal hydride bed, adopting metal hydrides with a sufficiently flat plateau, reducing reactor heat capacities and its mass, and highly exchanging efficient sensible heat. The COP of MHHP rises with temperature increase of driving heat source, while the range of temperature upgrading reduces with the temperature increase of driving heat source.