Waste Heat Driven Multi-Bed Adsorption Chiller: Heat Exchangers Overall Thermal Conductance on Chiller Performance

Abstract

The results of an analytic investigation on the influence of the thermal conductance of a sorption element (adsorber/desorber), evaporator, and condenser on the performance of a three-bed silica-gel-water adsorption chiller are presented with consideration given to the thermal capacitance ratio of the adsorbent and metal of the adsorber/desorber heat exchanger. The analysis was performed by using a cycle-simulation model developed by the authors. The chiller is driven by exploiting waste heat at a temperature 60 and 95°C with a cooling source at 30°C for air conditioning purpose. The results show that the cycle performance is strongly affected by the thermal capacitance ratio and sorption element thermal conductance due to several sensible heating/cooling requirements resulting from batched cycle operation. The model is somewhat sensitive to the thermal conductance of the evaporator, and the thermal conductance of the condenser is the least sensitive parameter.