Experiment System Of A Small Steam Ejector And The Investigation Of Its Performance

With more and more attentions on the energy shortage and environmental issues, the steam ejector experimental study by using of the industrial waste heat and solar energy has very important significance. Although the steam jet refrigeration system has many advantages, but traditional compression refrigeration system continues to dominate the refrigeration market. The main reason is the steam ejector work efficiency is low, which is the core of the steam ejector refrigeration system. In order to promote its widespread application, enhance the performance of the ejector has become the key point to the prograss of steam jet refrigeration system. In recent years, Because of many advantages of CFD, numerical analysis of ejector has been paid more attention to, there is a lot of numerical simulation of jet has been taken in flow field, and the influence of operating parameters and structural parameters on jet pump performance. But experimental data from the literature is very limited and difficult to get confirmation of the applicability of theoretical models and reliability of numerical methods of the jet, which has restricted the application of numerical simulation results. In order to in-depth research and accurately knowledge of the performance of the ejector, and to provide experimental data support for the numerical simulation, it is necessary to design and build the steam injection system experimental platform and to do more experimental study on the performance of the jet pump.The main research studies contained in this paper are as follows:(1)To improve the small steam injection experiment system. by designing voltage stabilization system which included a single-seat pressur. regulating valve, PID, pressure transmitter, stainless steel tank etc, in order to obtain the stable working steam pressure(2) Based on the experiment system, by changing the operating parameters of the ejector (pressure of working steam pressure, evaporator evaporation and spray for export back pressure), obtained the experimental results under different operation parameters of ejector steam mass flow rate and spray ejector coefficient curve, the critical pressure, etc. And the error analyze the experimental results.(3)The models based on the main injector of the experimental system, using computational fluid dynamics (CFD) method, based on ANSYS FLUENT 14.0 computing platform, to simulate the internal flow field of ejector, obtained the experimental results in the center of pressure distribution under different operation parameters, ejector coefficient curve and location of the shock wave and critical pressure, etc. Compare the experimental data and numerical simulation results, and discussion of the accuracy of numerical simulation. At the same time, using the simulated results put forward proposals for improving the injector.This study shows that, in a certain area, as the pressure of working steam rising, ejector steam flow will also increase, when working steam pressure reaches a certain value, the ejector steam flow rate decrease with the increase of working steam pressure, with the rise of working steam pressure, the ejector critical back pressure would also rising, while the entrainment ratio would decreases when it's in congestion state, with the rise of entrainment steam pressure, the entrainment ratio of ejector showed a tendency to increase, when working steam pressure is high, by using the ideal gas model assumes that the numerical simulation results have better consistency with the experimental data, but when the working steam pressure is lower, this assumption is not necessarily reasonable, so it is need to consider using wet steam model to analyze.