摘要
研究自走式秸秆制粒机扬尘的动态扩散过程对抑制扬尘的形成和扩散具有重要作用。将欧拉混合多相流模型与动态网格模型相结合,运用瞬态数值模拟方法计算不同行驶速度和环境风速下的扬尘动态扩散过程,分析自走式秸秆制粒机在行驶过程中灰尘颗粒的动态分布、浓度随时间的变化规律、空间位置与浓度的影响关系以及行驶速度对空气的扰动情况。结果表明:行驶速度能够增强流动区域气流扰动,提高空气的流动速度,扩大灰尘影响范围;当制粒机以5km∙h^(-1)行驶时,灰尘影响范围1.97m;当制粒机以10km∙h^(-1)行驶时,灰尘影响范围3.88m;随着环境风速等级增大,灰尘颗粒吹拂距离增大,在风速方向上扩散距离增长,灰尘对环境影响范围扩大;当风速10m∙s^(-1)时,起始点最高浓度24.2kg∙m^(-3),掉落地面最远距离3.67m;风速静止和轻风时,起始点最低浓度18.7kg∙m^(-3),掉落地面距离1.14~1.23m之间。灰尘颗粒在风道中心区域浓度较高,通过储料笼缝隙向四周扩散,距离储料笼越远,颗粒浓度越低。研究结果对揭示扬尘形成机理和抑制扬尘扩散具有指导意义。
The dynamic diffusion process of dust about the mobile straw briquetting machine was a great significance to the formation and diffusion of the dust emission.In this paper,the dynamic response of dust under different driving speeds and ambient wind speeds was calculated by using the transient numerical simulation method,which combines the Euler mixed multiphase flow model with the dynamic grid model.The dynamic distribution of the dust particles,the variation of the dust concentration with time,the relationship between the space position and the dust concentration,and the disturbance of the traveling speed to the air were analyzed.The results showed that the driving speed can enhance the air flow disturbance in the flowing area,increase the air flow speed and expand the dust influence range.When the vehicle is 5km∙h^(-1) the influence range of dust is 1.97m,and when the vehicle is 10km∙h^(-1),the influence range of dust is 3.88m.The distance of dust blowing is increased with the increase of the ambient wind speed,and the influence range is increased.When the wind speed is 10m∙s^(-1),the maximum concentration is 24.2kg∙m^(-3) and the maximum distance to the ground is 3.67m.When the wind is still and light the minimum concentration is 18.7kg∙m^(-3) and the distance to the ground is between 1.14 and 1.23m.The concentration of dust is higher in the central area of the air duct,and is diffused around through the gap of the dense material storage cage.The results showed that the analysis of the dynamic process of dust is an effective way to understand and master the formation of dust,and plays an important role in further controlling the dispersion of dust.In order to control the formation and diffusion of dust,it is possible to reduce the vehicle speed in a windless or less windy weather.
作者
王国峰
任德志
金钊
白雪卫
宫元娟
WANG Guo-feng;REN De-zhi;JIN Zhao;BAI Xue-wei;GONG Yuan-juan(College of Engineering,Shenyang Agricultural University,Shenyang 110161,China)
出处
《沈阳农业大学学报》
CAS
CSCD
北大核心
2021年第2期189-196,共8页
Journal of Shenyang Agricultural University
基金
国家自然科学基金项目(51405311)
辽宁省重点研发指导计划项目(2019JH8/10200019)。
关键词
自走式秸秆制粒机
扬尘
动网格
瞬态模拟
运移扩散
mobile straw briquetting machine
dust
dynamic mesh
transient simulation
migration diffusion
