道路吸尘清扫车吸嘴的颗粒去除性能的数值模拟研究

道路吸尘清扫车吸嘴的颗粒去除性能的数值模拟研究(中文9000字,英文6000字)
摘要：本文的目的是探讨道路吸尘清扫车吸嘴的颗粒去除性能数值。基于粒子吸气过程的计算流体力学软件(CFD)，构建了一个集成的三维数值模型。气流通过吸嘴被视为连续时，颗粒仍作为分散的模型。选择雷诺兹应力模型（RSM）和离散颗粒模型（DPM）以准确预测空气和颗粒流。数值模拟结果表明，清扫车的行驶速度和吸嘴的压降对颗粒去除性能产生很大的影响。去除效率在清扫车行驶速度较低或更高的压力降时会增加，小尺寸颗粒比大尺寸颗粒，在相同的操作条件下相比，具有更高的去除效率。此外，去除颗粒的质量流率会随着清扫车的行驶速度增加而增加。因此，我们应该选择在除效率高，能耗低，和高去除质量流率之间找到一个平衡。通过数值模拟，对街道吸尘清扫车的道路表面除去颗粒的有效性进行评估，并获得最佳操作条件。此外，获取更多的信息以便更好地了解吸嘴颗粒的抽吸过程。
 

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.