Influence of initial bed temperature on bed performance of an adsorption refrigeration system

摘要

The study deals with the complete dynamic analysis (numerical and practical) of an existing adsorption refrigeration system. The adsorption refrigeration setup is available at Indian School of Mines (Dhanbad, India), Mechanical engineering department. The system operates with activated carbon (as an adsorbent) and methanol (as refrigerant).Numerical model is established base on energy equation of the heat transfer fluid (water) and transient heat and mass transfer equations of the adsorbent bed. The input temperature of heat source is 90°C, which is very low compared to other low-grade energy input refrigeration system. The thermo-physical properties of an adsorptive cooling system (using activated carbon–methanol pair) are considered in this model. In this analysis influence of initial bed temperature (T1) on the bed performances are analysed mathematically and experimentally. The simulation and practical results of this system show that the cycle time decreases with increase in initial bed temperature and the minimum cycle time is 10.74 hours (884 minutes for practical cycle) for initial bed temperature of 40°C. Maximum system COP and specific cooling capacity are 0.436 and 94.63 kJ/kg of adsorbent under a condenser and evaporator temperatures of 35°C and 5°C, respectively. This analysis will help to make a comparison between simulated and experimental results of a granular bed adsorption refrigeration system and also to meet positive cooling needs in off-grid electricity regions.