“U＋L”型通风综采面合理挡风帘长度确定

Determination on reasonable length of wind curtain for ‘U + L' type ventilation in fully mechanized face

合理长度的挡风帘可以有效减少工作面漏风量,避免瓦斯超限、爆炸等事故发生,保证工作面安全生产。模拟了有无挡风帘时和不同挡风帘长度时"U+L"型通风综采面采空区流场、瓦斯分布及上隅角等地瓦斯情况,验证了数学模型和参数的适用性,分析了挡风帘对采空区压力分布及瓦斯分布的影响,确定了"U+L"型通风综采面合理挡风帘长度。研究表明:挡风帘对采空区压力及瓦斯分布都有重要影响,挡风帘可以使采空区内特别是挡风帘遮挡区域采空区压力下降、瓦斯浓度升高;随着挡风帘长度的增加,上隅角瓦斯浓度变化不大,采煤机机尾瓦斯浓度逐渐降低,滞后横川瓦斯浓度呈增大趋势;综合分析确定该采面合理挡风帘长度为120 m。

The wind curtain with reasonable length can effectively reduce the air leakage of working face,avoid the occurrence of gas accumulation,gas explosion and other accidents,and ensure the safe production of working face. The flow field in goaf,gas distribution and gas situation in upper corner and other places of ‘U ＋ L＇type ventilation in fully mechanized mining face under the conditions of with or without wind curtain and different length of wind curtain were simulated. The applicability of mathematical model and parameters was verified. The influence of wind curtain on pressure and gas distribution in goaf was analyzed,and the reasonable length of wind curtain for‘U ＋ L＇type ventilation in fully mechanized face was determined. It showed that the wind curtain has an important influence on the pressure and gas distribution in goaf,and it can make the pressure drop and the gas concentration rise,especially for the occlusion region by wind curtain in goaf. With the increase of wind curtain length,the gas concentration in upper corner has little change,the gas concentration in tail of shearer decreases gradually,and the gas concentration in lag crossheading increases. Through comprehensive analysis,the reasonable length of wind curtain in the mining face was determined to be 120 m.