Simulation Of Chemical Adsorption Refrigeration System Driven By Engine Exhausted Gas

ABSTRACT:Engine exhausted gas is a high-temperature waste heat can be fully utilized, the heat contained in exhaust gas equivalent to30%of the fuel heat of combustion, and its heat recovery has great socio-economic significance. Adsorption refrigeration is an environmentally friendly, low-grade energy available green refrigeration technology, suit to vehicle’s engine exhaust heat recycling very much. In this paper, adsorption cooling method was used in engine exhaust heat recovery, the numerical simulation methods for adsorption refrigeration system operating characteristic analysis.Firstly, according to the characteristics of adsorbents and absorption refrigeration system to determine the appropriate use of the engine exhaust heat absorption working pair (calcium chloride-ammonia) and the way of cycling (three-bed cycles), and the introduction of improve the efficiency of the system heat and mass recovery measures was proposed.Secondly, based on equilibrium adsorption theory, thermodynamics method was used to analysis three-bed adsorption cooling system ideal cycle energy of each process, and based on calcium chloride-ammonia adsorption characteristics, cycle performance characteristics at different temperature ranges, different evaporation temperature, condensation temperature and the introduction of heat and mass recovery process were analyzed.Again, based on non-equilibrium adsorption theory, a mathematical model of heat and mass transfer in adsorption bed was established, and use fluent software to solve them, and discussion of the temperature distribution and variation of temperature during operation of the adsorbent bed, and the relationship between the parameters and the amount of adsorption in the bed was analyzed.Finally, the dynamic characteristics of the calcium chloride-ammonia chemical adsorption refrigeration system driven by engine exhausted gas was studied. Thermal dynamic model was established to simulate the performance of bed temperature, evaporation temperature, condensation temperature, evaporator and condenser outlet temperature in the running system, and the article summarizes the varieties of system performance parameters in the different evaporation temperature and condensation temperature. And preliminary analysis the system performance after introducing the heat and mass recovery processes.Conclusions of this paper can provide a reference for future research on various components of the chemical adsorption refrigeration system matching and optimizing the performance of system.