Research On Particle Removal Performance Of Vacuum Dust Suction Mouth

Abstract:Rubbish on the subway ballast bed always has bad effects not only on performance of the electrical equipment but also on cleanness of the outside surfaces of subway train. In China, the subway ballast bed is always cleaned by manpower at midnight, which is inefficient, labor-intensive and expensive in labor costs. Therefore, it is very important to improve the cleaning effect and the efficiency during the development process of subway. Based on3D modeling and dynamic mesh, the flow model of single phase and multiphase were adopted to simulate the flow field of vacuum dust suction mouth combining with the facilities on the subway ballast bed. Guidance for designing the vacuum dust suction mouth that used on subway ballast bed was proposed.The main research works are as follows:(1) Based on the parametric analysis of the expanding zone of the vacuum dust suction mouth, the effects of the expanding zone parameters on flow simulation were analyzed. The results show that the calculation accuracy depends on the threshold values of geometric parameters of the expanding zone. The influences can be neglected when its geometric parameters are larger than the threshold values. The computation model of the expanding zone without corner can be used to improve computational efficiency if the demand of calculation accuracy isn’t very high.(2) Based on the threshold values of the expanding zone parametric of the vacuum dust suction mouth, the effect of the distance between the vacuum dust suction mouth and the facilities of the subway ballast bed on performance of the vacuum dust suction mouth moving at a certain velocity was researched. The results show that when the gutter or the cable is far away from the vacuum dust suction mouth, the cleaning effect will not be affected. Once the distance is less than its threshold values, the cleaning effect will be reduced. The cleaning effect of the vacuum dust suction mouth will not change at any distance between the vacuum dust suction mouth and the transponder.(3) Based on the threshold values of the expanding zone parametric of the vacuum dust suction mouth, the structural parameters of the vacuum dust suction mouth were analyzed to get their relations with cleaning effect. The results show that with the increase in the width of dust suction mouth, the vacuum in the exhaust pipe is reduced, which makes against sucking dust. When the exhaust pipe diameter is less than1/3of the length of dust suction mouth, it is beneficial for a progressive increase in dust suction performance with the increase in exhaust pipe diameter. When the oblique angle of exhaust pipe with backboard does is less than110°, the vacuum effect gets better with the increase in their oblique angle. Finally, a new improved dust suction mouth was put forward. This improved dust suction mouth was certified no turbulence and energy-efficient by computing the flow model of single phase and multiphase.