Numerical Analysis Of Performance Of Shrinking Gas Collecting Tube Type Vortex Tube Separator

There are more sandstorms in the northern regions of our country,especially in spring and autumn.The continuous sandstorm not only affects people’s lives,but also has a greater impact on the diesel engines of locomotives.When the sand enters the engine,part of it will be adsorbed on the surface of the parts.Under the mechanical and chemical action,a large number of parts will be damaged.If it is not handled in time,the accumulation of excessive sand will also cause the blockage of the pipeline in the diesel engine.In the past,we used steel mesh filter and cyclone separator as the intake protection device of diesel engine,but in areas with more wind and sand,the filtering capacity of these two types of separators is not very good,so more efficient separator design is imminent.In this article,a shrinking gas collecting tube type vortex tube separator is researched,using CFD method,based on the theoretical basis of gas-solid two-phase flow,and its internal flow field is numerically simulated and analyzed.From the structural parameters of the separator,the influence of different structural parameters on the flow field and performance of the separator is studied;Use regression design method to optimize the structure parameters of the separator to obtain a structure with high separation efficiency and low total pressure loss;the influence of the optimized separator working conditions on the performance of the separator is studied.The main contents of the research are as follows:The results of the research on the influence of structural parameters on the separator are:as the diameter of the gas collector increases,the main flow outlet of the separator increases,the total pressure loss decreases,and the separation efficiency also decreases;the overall length of the gas collector increases,the separator’s total pressure loss and separation efficiency are slightly increased;the increase in the length of the spiral blade will reduce the pressure loss and separation efficiency.Combining parameter optimization software and the simulation data of the influence of structural parameters on the separator,the regression design method is used to optimize the structural parameters of the separator.After regression equations and significance analysis,the optimal structural parameters of the separator are obtained.The diameter of the port is6 mm,the length of the blade is 17 mm,and the total length of the collecting pipe is 22.5mm.At this time,the total pressure loss is 91.15 Pa,and the separation efficiency is 95.7%;the size of the influence of structural parameters on the total pressure loss and separation efficiency is that the diameter of the gas collector is larger than the spiral blade The length is greater than the total length of the gas collecting pipe.The results of the research on the effect of different working conditions on the performance of the separator on the optimized structure model are: with the increase of particle diameter,the separation efficiency shows an upward trend in the range of 0.2 to 7μm,and the separation efficiency reaches 100% at 7μm;In the interval of 7 to 20μm,the separation efficiency is maintained at 100%;in the interval from 20 to 200μm,the separation efficiency is slowly decreasing;as the particle density increases,the separation efficiency gradually increases;If the back pressure of the dust removal port increases,it will increase the total pressure loss,the separation efficiency will be improved at the same time.Compared with the traditional vortex tube separator,the shrinking gas collecting tube type vortex tube separator has better separation performance.