综放面多尘源粉尘分布规律数值模拟及实测

为解决综放工作面粉尘浓度高的问题,掌握各作业工序粉尘浓度空间分布规律,有效指导粉尘控制工作,依据气固两相流理论,运用Fluent软件对综放工作面割煤、移架、放顶煤、转载各工序单独及同时作业时的粉尘分布规律进行数值模拟,并与现场实测数据进行对比分析.结果表明:割煤作业粉尘沿采煤机机道扩散的同时向人行道空间扩散,需在滚筒尘源处控尘,并在采煤机外侧采取水幕帘除尘措施;移架作业时人行道粉尘浓度高于机道粉尘浓度,需在机道空间和人行道空间均设置架间喷雾;放煤作业粉尘沿人行道空间分布较大,需在放煤口采取隔尘措施;转载点局部风速大,粉尘影响范围较广,应采取密封等措施.还应在放煤和割煤作业之间增加全断面喷雾降尘装置.

Numerical simulation and field measurement of dust distribution for multi-source dust at fully mechanized caving face

To lower dust concentration at fully mechanized caving faces, master spatial distribution rules of dust in various operation processes, and effectively direct dust control, the thesis, on the basis of gas-solid two-phase flow theory, carried out the numerical simulations with Fluent software to trail the dust distribution rules of coal cutting, support moving, sub-level caving, and transshipping at fully mechanized caving faces in single and multiple processes, and the results of which were made comparison with the site data. The findings were as follows. Coal-cutting dust spreads not only along the chute of shearer, but to footway, thus dust control near the drum and water curtain for dust reduction are necessary. Dust concentration of footway is higher than that of chute when moving supports, therefore, mist spray between supports should be equipped both in footway and chute. Considering the higher dust concentration of sub-level caving at the footway, dust separation should be done in the drawing opening. Higher air velocity at partial area of transpersite and a widespread effect of dust require the measures like sealing be adopted. In addition, full-section spraying devices should be installed between processes of sub-level caving and coal cutting.