西安建筑科技大学学报(自然科学版)

工业颗粒体输送系统如煤粉、铝粉、水泥等输运过程存在大量的粉尘逸散问题,成为了工作场所的空气环境污染源头.溜槽是工业颗粒体输送系统的关键部件之一,溜槽通道的形状大多呈“Z”型,它是产生污染、治理粉尘污染的出发点.首先通过试验数据验证了Discrete Phase Model的正确性,之后利用Fluent软件对溜槽内颗粒粒径为300～500 μm,密度为700～2 800 kg/m3及质量流量为0.05～0.2 kg/s的不同工况进行了数值计算.结果表明,随着颗粒质量流量增大卷吸空气速度明显增大; 随着颗粒密度和粒径减小,颗粒越容易从料流核心区向外扩散; 颗粒密度对其速度有较大影响,随着颗粒密度增大颗粒加速阶段持续时间越长.研究结果为工业颗粒体输送系统的粉尘逸散过程通风系统的设计提供了理论依据.

There is a large amount of dust escape problem in the transportation process of industrial particulate transportation systems such as coal powder, aluminum powder and cement, which has become the source of air pollution in the workplace.Transfer chute is one of the key components of the industrial particle delivery system.Most of the chute channel is “Z” type, which causes pollution and therefore is also the starting point of the dust pollution control.In this paper, the discrete phase model in Fluent software was used to simulate the particles of different mass flow(0.05～0.2 kg/s), diameter(300～500 μm)and density(700～2 800 kg/m3), obtaining the entrained air velocity distribution, particle concentration distribution and particle velocity in the course of a horizontal projectile motion under different working conditions.Results show that the entrained air velocity increases significantly with the increase of the particle mass flow rate. As the particle density and diameter decrease, the particles are more likely to diffuse outward from the material flow core region.The density has a greater influence on particle velocity.As the particle density increases, the duration of the particle acceleration phase increases.Research results provide a theoretical basis for the design of the ventilation system of the dust escape process in the industrial particulate transport system.

引言
1 气固两相流数值模型
2 物理模型及验证
3 结果及讨论
4 结论

图1 物理模型
Fig.1 Physical model

表1 模型部件及尺寸<br/>Tab.1 Model parts and size

表1 模型部件及尺寸
Tab.1 Model parts and size

表2 边界条件
Tab.2 Boundary conditions

图2 颗粒竖直方向速度对比(400 μm、1 400 kg/m3)<br/>Fig.2 Comparison of particle vertical (400 μm、1 400 kg/m3)

图2 颗粒竖直方向速度对比(400 μm、1 400 kg/m3)
Fig.2 Comparison of particle vertical (400 μm、1 400 kg/m3)

图3 颗粒竖直方向速度对比(500 μm、2 800 kg/m3)<br/>Fig.3 Comparison of particle vertical velocity (500 μm、2 800 kg/m3)

图3 颗粒竖直方向速度对比(500 μm、2 800 kg/m3)
Fig.3 Comparison of particle vertical velocity (500 μm、2 800 kg/m3)

图4 不同断面卷吸空气速度随颗粒质量流量变化<br/>Fig.4 The entrained air velocity varies with the particles mass flow at different cross sections

图4 不同断面卷吸空气速度随颗粒质量流量变化
Fig.4 The entrained air velocity varies with the particles mass flow at different cross sections

图5 不同断面卷吸空气速度随颗粒粒径变化<br/>Fig.5 The entrained air velocity varies with the particles diameter at different cross sections

图5 不同断面卷吸空气速度随颗粒粒径变化
Fig.5 The entrained air velocity varies with the particles diameter at different cross sections

图6 不同断面卷吸空气速度随颗粒物密度变化<br/>Fig.6 The entrained air velocity varies with the particles density at different cross sections

图6 不同断面卷吸空气速度随颗粒物密度变化
Fig.6 The entrained air velocity varies with the particles density at different cross sections

图7 不同断面颗粒物浓度随质量流量变化<br/>Fig.7 The particulate concentration varies with the particles mass flow at different cross sections

图7 不同断面颗粒物浓度随质量流量变化
Fig.7 The particulate concentration varies with the particles mass flow at different cross sections

图8 不同断面颗粒物浓度随颗粒粒径变化<br/>Fig.8 The particulate concentration varies with the particles diameter at different cross sections

图8 不同断面颗粒物浓度随颗粒粒径变化
Fig.8 The particulate concentration varies with the particles diameter at different cross sections

图9 高度方向不同断面颗粒物浓度随颗粒物密度变化<br/>Fig.9 The particulate concentration varies with the particles density at different cross sections

图9 高度方向不同断面颗粒物浓度随颗粒物密度变化
Fig.9 The particulate concentration varies with the particles density at different cross sections

图10 颗粒物性对颗粒速度影响<br/>Fig.10 Effect of particle properties on particle velocity

图10 颗粒物性对颗粒速度影响
Fig.10 Effect of particle properties on particle velocity

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备注

引言

1 气固两相流数值模型

2 物理模型及验证

3 结果及讨论

4 结论

期刊信息