摘要
针对综掘工作面掘进过程中粉尘污染问题,设计了一种新型高效的风幕控尘除尘系统,利用风幕风速衰减试验分析了风幕风速与距出口距离衰减的关系,当风幕末端风速达到2 m/s以上就能够有效控制呼吸性粉尘逃逸,另外,利用数值模拟的方法,对风幕控尘除尘系统工作原理进行了模拟,当风幕初速度为15 m/s、除尘风筒负压为-250 Pa时,风流到达巷道壁时的风速均达到了3 m/s以上,风幕控尘除尘系统起到了很好的控尘和除尘作用。并对压入式通风+湿式除尘机除尘的方式进行了数值模拟,压入式通风的风流大部分被除尘风筒吸入,掘进头和压入式风筒与除尘风筒重叠段形成了无风区,大部分粉尘颗粒和瓦斯不能够及时排出,给生产带来了极大的安全隐患。
In this paper,the author intends to introduce a new type of highly efficient dust-control and removal system with the wind-curtain in hoping to solve the headache problem of dust-pollution in the fully mechanized coal mine. To solve the long-lasting problem of dust-pollution,we have first of all made an exploration of the relation between the wind speed and the distance of wind curtain outlet,which is followed by an experiment with the wind curtain velocity attenuation. And,next,we have made a numerical simulation to simulate the working principle of the dust control and removal system via a software named Fluent CFD. In the simulation process,we have conducted a smog tracer experiment to prove that it is possible for the wind curtain to control effectively the respiretable dust emission when the wind end speed is above 2 m / s. For example,when the tunnel is 4. 5 m wide and 3 m high,the initial speed of the wind curtain should be 15 m / s. And,when the wind reaches the tunnel wall,its speed should be over 3 m / s. However,when the dedusting-oriented pressure is- 100 Pa,most of the dust particles are still likely to get escaped. And,even if the dedusting duct pressure is about-200 Pa,there is still some small amount of dust particles to escape.However,when the dedusting duct pressure is- 250 Pa,no dustparticle can get escaped all. Thus,it can be seen that the simulation results prove that,even when the final velocity of air curtain reaches3 m / s,there still exists a possibility that the entrainment effect of the air curtain still play a leading function when the dedusting conducive pressure is small. Therefore,it proves a failure to raise the airflow velocity of the wind curtain unilaterally. Instead,there is a real must for the dedust fan to supply ensure enough negative pressure that can help to have a good dust removal effect. Thus,it can be seen that our numerical simulation is in a position to simulate the dedusting method of successful positive pressure ventilation in combination with the negative pressure along the dededusting function.What is more,most of the airflow of positive pressure ventilation is sucked into the wet dedusting machine. Therefore,since the excavation face and the overlapping segments of the two duct functions are likely to result in a calm area,most of dust particles and gas can not be discharged in time,whereas,in contrast,the control and removal dust system with the wind curtain can be taken as a idealistic solution to the headache problem of dust-pollution in the fully mechanized coal mine.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2015年第4期33-37,共5页
Journal of Safety and Environment
基金
国家自然科学基金项目(U1261121)
关键词
安全工程
综掘工作面
通风除尘
数值模拟
safety engineering
fully mechanized excavation face
ventilation dedusting
numerical simulation
