吹吸式地铁轨间区域清扫流场的数值分析

为提高清扫车的清扫效率,采用计算流体力学方法对吹吸式清扫流场进行计算,结合气固两相流模型分析结构参数对清扫效果的影响规律,并采取基于权矩阵分析的多目标正交试验方法,进行位置参数的优化. 研究结果表明:吹嘴宽度在不大于吸嘴宽度的0.93倍之内增大有利于提高清扫效率；吹嘴高度不小于吸嘴高度的0.92倍时,增大吹嘴高度可提高清扫效率,但降低了近地面平均速度和吹嘴出口速度,不利于尘粒的起动；吸嘴倾角为20°、吹嘴倾角为20°、吹嘴和吸嘴之间的距离为700 mm、吹吸嘴离地高度为20 mm时,吹吸式清扫方式的清扫性能最优；吹吸式清扫流场的近地面气流速度大,气流从吹嘴向吸嘴方向运动且紧贴地面,不存在气流外泄造成的二次污染. 吸嘴倾角和吹嘴倾角对吹吸式清扫流场的清扫性能影响最大,其次是吹嘴和吸嘴之间的距离,吹吸嘴距离地高度对清扫性能的影响最小.

Numerical analysis on blowing-suction cleaning flow field between subway rails

To improve the dust collection efficiency of sweepers, the computational fluid dynamics method was applied to simulate the blowing-suction cleaning flow field. Influence of structural parameters on cleaning effect was analyzed combined with the gas-solid two-phase flow model. The multi-objective orthogonal test method based on weight matrix analysis was used to optimize the position parameters. Results show that when the width of the blow mouth was less than 0.93 of the width of the suction mouth, it is beneficial for improving cleaning efficiency with the increase of the width of the blow mouth. When the height of the blow mouth was more than 0.92 of the height of the suction mouth, the cleaning efficiency was improved with the increase of the height of the blow mouth, but the mean velocity near the ground and the outlet velocity of the blow mouth were reduced, which was not conducive to blowing up the dust. When the inclination of the blow mouth was 20°, the inclination of the suction mouth was 20°, the distance between the blow mouth and the suction mouth was 700 mm, and the height from the two mouths to the ground was 20 mm, the cleaning performance of the blowing-suction cleaning method was optimal. The airflow velocity was high near the ground in the blowing-suction cleaning flow field, where the airflow moved from the blow mouth to the suction mouth and the direction was close to the ground. There was no secondary pollution caused by the leakage of the airflow. The inclination of the blow mouth and the inclination of the suction mouth had the greatest influence on the cleaning performance, followed by the distance between the blow mouth and the suction mouth, and the height from the two mouths to the ground had the least effect.