机掘工作面旋转射流屏蔽通风最佳送风角度的确定

Determination of the best air-supply angle of the rotational jet shield ventilation at tunneling working face

为了确定最佳的送风角度,采用数值模拟和模型试验,对不同送风角度下机掘工作面旋转射流屏蔽通风流场和粉尘质量浓度分布进行研究。研究结果表明:在其他设计参数确定的情况下,工作面风流流场和粉尘质量浓度分布与送风角度密切相关;当送风角度θ为75°时,旋转射流屏蔽通风流场能在工作面形成完整的屏蔽风幕,且组合风口前方吸气速度和负压沿轴向衰减较其他送风角度吸气速度和负压沿轴向衰减缓慢,组合风口控尘效果最佳,组合风口后方粉尘质量浓度降至24 mg/m3,旋转风幕隔尘效率高达85.9%。

To determine the best air-supply angle, the flow field and dust mass concentration distribution of the rotational jet shield ventilation under different air-supply angles were investigated by numerical simulation and model experiments. The results show that the flow field and dust mass concentration distribution are closely related to air-supply angle with the other design parameters fixed. When the air-supply angle isθ=75°, a complete air curtain can be formed at the tunneling working face, and the suction velocity and negative pressure in front of the combined tuyere in the axial direction are lower than those of other air-supply angles. The best dust control effect is obtained, the dust mass concentration falls to 24 mg/m3, and the dust-isolating efficiency of rotational jet reaches up to 85.9%.