PERFORMANCE OF COMPRESSOR DRIVEN METAL HYDRIDE COOLING SYSTEMS UNDER DIFFERENT OPERATING CONDITIONS

摘要

The performance of a compressor driven metal hydride cooling system is analyzed using a mathematical model which takes into account the transient nature of the compressor, conditioned space and the external fins in the reactor tubes. The design is first optimized to satisfy a given comfort and pulldown criterion at an ambient temperature of 32℃. Results are obtained to study the performance of the system at higher ambient temperatures. It is observed that the coefficient of performance of the system decreases with an increase in ambient temperature whereas the reverse trend is exhibited for average specific power. It is also noted that though reasonable comfort temperatures are obtained in the conditioned space with rise in ambient temperatures, there is a drastic rise in the operating pressures of the system. The study also predicts the effect of change in compressor speed, speed of the blowers and cycle time on the performance of the system under extreme operating temperatures. It is observed that controlling speed of the blowers is the most effective technique to enhance the performance.