Theoery And Experiment Research Of An Ammonia-Water Absorption Refrigeration Cycle

Focusing on ammonia-water absorption refrigeration cycle, this paperstudies the theory and experiments of the cycle. In the paper, the operationtemperatures, pressures and the changes of concentration were analyzed.The target to energy conversion of heat pump and the irreversiblecharacteristics were discussed. According to the analysis of T-S diagrams,the coupling relationship between the heat-pump subcycle and theheat-engine subcycle was proposed. Furthermore, the influences ofheat-source temperature to system performance were evaluated. With software Aspen Plus, the characteristics of rectifier, absorber andwhole process were simulated. The influences of condensation-temperature,evaporation temperature, generation temperature and circular ratio to thecoefficient of performance were studied. The relationship betweengeneration temperature and circular ratio was analyzed. And therelationship between reflux ratio and separation effect was analyzed. Theinfluence of cooling water temperature at absorber entrance tocondensation load was discussed. The influence of weak solution IV北京化工大学硕士研究生毕业论文concentration to heat transfer and mass transfer were discussed too. After have analyzed former experiment result, the experimental deviceconfiguration was rebuilt. And the process stability was improved. By theimprovements for operation conditions and procedures, the COP reached0.278 when the temperature at rectifier bottom is 71.8℃. Pilot studyprovesthat the experimental device possess refrigeration performance. It comes tothe conclusion that the efficient-packing is helpful to improve theseparation effect of rectifier, moreover, the plate heat-exchanger andfalling-film absorber are appropriate, respectively. Based on researches on the utilization of renewable energy and thematching of heat source temperatures of heat pump, this work proposes anammonia absorption cycle system for refrigeration and heat-supply, whichis a the heat pump combined heat sources. While combing solar energy andgeothermal heat and based on the operation parameters proposed in thework, the system achieves COPR of 0.583 at refrigeration condition andCOPHP of 1.509 at heat-supply condition, that are higher than conventionalsystem by 12.0% and 16.2%, respectively. It shows that is reasonable toadopt the heat pump combined heat sources.