摘要
以核设施退役现场反铲挖掘机挖斗卸料过程中产生的粉尘流为研究对象,依据气固两相流理论,运用Fluent软件对粉尘流运移扩散规律进行了数值模拟,研究了多个基准风速下粉尘流的运移形态,并进行了对比分析。结果表明,特定的基准风速条件下,粉尘流会形成特定的运移形态,且当基准风速从1.5 m/s增大到4 m/s时,粉尘流下部两条质量浓度最大值区域会逐渐发生并拢并最终合并,这种变化的直接动力是粉尘流周围的总压差,粉尘扩散范围也会逐渐增大。
This article would like to explore the free-falling dust be- havior in the open space under the impact of the horizontal wind in hoping to identify the actual characteristic features of the wind in the different velocities based on the simulation platform--Fluent. For this purpose, we have first of all built up a 150 m × 80 m × 50 m cubic computational model with a 0.94 m × 0. 1 m rectangular discharge opening to simulate the decommission field of the nuclear facilities. The bottom of the computational model can be placed on the ground with its roughness being 0.1 m. And, next, the discharge opening can be designed in a height of 6 m above the ground with the horizon- tal wind speed in accordance with the logarithmic distribution law. With everything ready as is mentioned above, we have made a careful simulated comparison between the different diffusion forms of the dust flow under the six kinds of reference horizontal wind speed with each other in the article. The simulation results show that the dust flow tends to reveal a special diffusion form while the simulated is set up at 2 m/s. At the same time, on the horizontal plane in an area of 2 m2 and the part below it, the mass concentration of the dust flow edge should be laid out higher than that of the dust flow central area whereas the horizontal plane of 4 m and those above it, the mass con- centration in the central area is higher than that in the edge area. What is more, when the reference wind speed increases from 1.5 m/s to 4 m/s, the two areas which have the largest mass concentration in the lower-part of the dust flow draw close to each other gradually and finally come to join. The direct momentum that has enacted the change is the total-pressure difference around the dust current so that the diffusion scope of the dust flow can be extended more freely. Therefore, when it comes to consider the management and technical measures for the dust suppression and elimination, it is necessary to take different measures to control the lower-part and the upper
出处
《安全与环境学报》
CAS
CSCD
北大核心
2015年第2期266-271,共6页
Journal of Safety and Environment
基金
湖南省重大专项(2012FJ1007)
关键词
环境工程学
核设施退役
开放空间
自由下落
粉尘治理
environmental engineering
nuclear facilities decommis-sion
open space
free-falling
dust control
