Performance Analysis And Simulation Of Thermodynamic Model In Steam Ejector Refrigeration System

With the improvement of living standards, the use of air conditioning increasedwidespread. Now, energy consumption and environmental pollution problems have becomemore severe caused by the use of mechanical compression refrigeration system, based onenergy-saving and environmentally-friendly, steam jet refrigeration system is becoming hotspots. This is because the cooling system use the ejector to take the place of traditionalcompressor, what is more, the ejector has a simple structure, no moving parts, the costs ofoperation and maintenance is low, last but not least, the jet refrigeration system enables to usethe low-grade renewable energyEjector enables to achieve the exchange of energy and final output medium pressuremixed fluid in the way of mixed two streams together, but due to the complexity of internalphysical state and flow field in ejector, making the design and selection of the ejector is nouniform criteria. There is a lot of research about ejector refrigeration at home and abroad,mainly concentrated in the designing of ejector structure, studying of refrigerants and settingof operating parameters et al, and has made some progress. However, many researchers buildmodels is limited to a single ejector thermodynamic model, the research about thethermodynamic model of the condenser and evaporator is less. In order to reflect the processof energy transformation in the cooling system, only through establish the thermodynamicmodel of ejector, condenser and evaporator, then, we can determine state parameters andstructural parameters.In this paper, the thermodynamic model of ejector, condenser and evaporator wereestablished based on the conservation of energy and heat transfer theory in the cylinder wall,then combine with the experimental data in existing literature, the model was validated. Inaddition, the best range of operating parameters was got based on this new model.Then, taking into account the advantage of numerical simulation (high flexibility, lowcost and repeatability), with help of fluid dynamics analysis software FLUENT to simulatethe process of two-dimensional flow field. Under certain preconditions, to constantly adjustthe size of the ejector, In order to arrive at the effect of ejector performance with the changeof size in ejector. The simulation results show that the rational selection of the structuraldimensions of the ejector can greatly improve the cooling efficiency.