复件 道路清扫车的改进外文文献及翻译内容.doc

复件 道路清扫车的改进外文文献及翻译内容 附录Ⅱ Numerical study on particle removal performance of pickup head for a street vacuum sweeper Bofu Wu Jinlai Men Jie Chen School of Mechanical English Shanghai Jiao TongUniversityShanghai200240China ABSTRACT The purpose of this paper is to investigate the particle removal performance of pickup head for a street vacuum sweeper numerically An integrated 3D numerical model was constructed based on particle suction process in computational fluid dynamics CFD software The airflow through the pickup head was treated as a continuum while particles were modeled as dispersed phase The Reynolds stress model RSM and discrete particle model DPM were chosen in order to predict the air and particles flow accurately The numerical simulation results show that the sweeper-traveling speed and the pressure drop across the pickup head have great effects on the particle removal performance The removal efficiency of particles increases with the lower sweeper-traveling speed or the higher pressure drop and small size particles have higher grade efficiency than that of large size particles under the same operating conditions Moreover the removal mass flow rate of particles increases with the higher sweeper-traveling speed Therefore a trade-off should be considered among high removal efficiency low energy consumption and high removal mass flow rate Through the numerical simulation the effectiveness of street vacuum sweeper for removing particles from road surface is evaluated and an optimal operating condition is obtained Besides more information is generated to better understand the particle suction process of the pickup head Keywords Pickup head Particle removal performance CFD Sweeper-traveling speed Pressure drop 1Introduction Currently there is a widespread concern over the pollution of particle matter Dust and silt are the major sources of particle matter pollution the removal of which therefore attracts considerable attention [1]