升温型金属氢化物热泵性能分析

Performance Analysis to Metal Hydride Heat Pumps for Temperature Upgrading

考虑到金属氢化物床的传热和换热器间显热回收等实际因素,提出了升温型金属氢化物热泵性能系数计算公式,为合理选择金属氢化物对,以及调整热泵的各种工艺参数提供了理论依据.结果表明:强化金属氢化物床的传热、采用平台倾斜度小的金属氢化物、减小反应器材料的比热和质量,以及换热器间高效率的显热回收,是提高热泵性能系数的有效措施.金属氢化物热泵的性能系数随驱动热源温度的升高而增大,但温升幅度随驱动热源温度的升高而减小.

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.