Characteristic Analysis Of Small Size Steam Ejector Applied To Refrigeration System

As people pay more attention to energy and environmental problems reducing energy consumption of air conditioning system,which can make the air conditioning system further energy-saving become the main research direction with many domestic and foreign experts. While the biggest advantages of the ejector used in refrigeration system is improving the pressure of fluid without Consuming mechanical energy.It is the ideal substitute, Nowadays the ejector has a wide range of applications including vacuum pumps, aircraft thrust augmentation, heat pumps for refrigeration and air-conditioning system and solid powder transportation。But the efficiency ejector used in refrigeration system is low and how to improve its efficiency is the crucial question.so firstly We must solve the design problems, Scholars of inside and outside have studied the jet refrigeration a lot,having gained much important results. it is important to re-think the method that marks out the design of conventional supersonic jet ejector, especially microl ejector. Because of the development of computer technology and numerical theoretical. It has been widely used in more and more fields.But also to promote the progress of ejector design theory. Through CFD simulation can clearly see complicated supersonic mixing process, as well as the shock wave, boundary layer interaction inside the injector. The introduction of CFD as ejector design tool provide much more help on the overall design of the system, and how to improve the ejector performance.But there has a great difference between the present for the micro ejector design theory and the traditional one-dimensional isobaric design theory.At the same time it is difficult to obtain accurate experimental data because the actual experimental conditions, it is even hard to machining of micro size injector, so from the perspective of numerical simulation of micro ejector design optimization, it is very practical and guiding significance.According to the One-dimensional isobaric design theory. After finished the calculation of geometric size,I iterative calculate the the system of ejector characteristic curve with R134refrigerant. Through the ejector characteristic curve qualitative judgment the efficient working range of the ejector. Although analysis the nozzle spacing, the mixing chamber diameter and other important structural parameters influence the injector performance and the CFD numerical simulation.Through the experimental data to verify the accuracy of the model, I examines the structural parameters and working parameters injector to the affect of inner flow field, and the injection coefficient. On the injector design calculation correction work, the jet ejector coefficient as a function of their structure parameters, but also summarizes the shock wave occurrence position and size on the structure parameters of; by changing the boundary conditions, simulation of the injector in the variable condition performance changes, as well as on system, looking for the simulation of optimum operating point.