The Influence Of Vortex Finder Parameter On Short-Circuit Flow In Double-Inlet Cyclone Separator

Cyclone separator is a device that uses centrifugal force to achieve gas-solid separation,and short-circuit flow is an important factor affecting separation performance.But the research on short-circuit flow is not enough.In this paper,the PV-type cyclone separator was taken as the research object,and the pure gas flow fields of the single-inlet and double-inlet cyclone separators were simulated and analyzed by means of numerical simulation.The influences of parameters such as vortex finder diameter and inlet area ratio on the flow field,especially the short-circuit flow,were investigated,and the flow fields of the double-inlet cyclone separator with different inlet area ratios were calculated.The main research results of the paper are as follows:(1)According to the change curve of the N value with the axial position of the inlet,three kinds of gas flow,namely short-circuit flow,transition flow and full-path flow,were quantitatively defined.The inlet areas corresponding to the three airflows were defined as the short-circuit flow area,the transitional flow area,and the full-path flow area,which clarified the source areas of each gas flow.(2)Based on the setting of uniform incidence of gas flow at the inlet of the cyclone separator,the calculation of the short-circuit flow rate is transformed into the problem of determining the area of the inlet short-circuit flow.The method based on the position of the boundary between the inlet short-circuit flow area and the non-short-circuit flow area was innovatively proposed.(3)For the single-inlet cyclone separator,with the diameter of the vortex finder increases,the proportion of short-circuit flow increases;For the double-inlet cyclone separator,with the diameter of the vortex finder increases,the short-circuit flow first decreases,but when the diameter of the vortex finder increases to a certain extent,the short-circuit flow does not change.(4)The inlet form has a significant impact on the flow field in the separator.When (?)=0.317、0.4、0.467,the short-circuit flow of a double-inlet cyclone is higher than that of single-inlet cyclone.But when (?)=0.5,the short-circuit flow of a double-inlet cyclone is lower than that of a single-inlet cyclone.(5)The change of the proportion of short-circuit flow is the result of the threedimensional velocity and symmetry.With the improvement of flow field symmetry and the decrease of three-dimensional velocity,the proportion of short-circuit flow increases.(6)K_A has a significant effect on the redistribution of inlet partitions.When K_A changes from 8.8 to 10.8,it mainly causes the redistribution of short-circuit flow area and transition flow area.When K_A changes from 10.8 to 15,it mainly causes the redistribution of the transition flow area and the full-circle flow area.