U型和U+L型通风采空区流场数值模拟研究

摘要

Numerical simulation was carried out on the flow field in the gob with U-type and U+L type ventilation modes by using Fluent software, and contrast analysis was made on the distribution of the gas concentration and the dangerous spontaneous combustion zone in the gob under two kinds of ventilation modes. The results showed that the gas concentration in the gob with U+L ventilation mode overall reduced as compared to that with U-type ventilation mode; the gas explosion scope moved to the deep part of the gob, but the width of gas explosion area became small. The gas concentration in the middle part of the gob rapidly increased along the gob strike under two ventilation modes. The dangerous spontaneous combustion zone under U+L-type ventilation mode moved to the deeper part of the gob as compared to that with U-type ventilation mode, and the width of the dangerous spontaneous combustion zone in the gob increased obviously.%利用Fluent软件，对U型和U+L型通风下的采空区流场进行了数值模拟，对比分析了两种通风方式下的采空区瓦斯浓度分布规律和采空区自燃危险区分布情况。结果表明：U+L型通风较U型通风采空区内瓦斯浓度整体降低；采空区瓦斯爆炸范围往采空区深部移动，但是瓦斯爆炸区域宽度变小。沿采空区走向方向，两种通风方式下的采空区中部瓦斯浓度上升较快。 U+L型通风较U型通风采空区内自燃危险区域往采空区深部移动，并且采空区自燃危险区域的宽度也明显增加。