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基于计算流体动力学基本理论,利用Fluent软件,采用控制容积法对描述流体流动的控制方程进行离散,用SIMPLEC(协调一致的压力耦合方程组的半隐式方法)算法来解算流场,使用标准k-ε壁面函数法解决近壁面的流动,在湍流充分发展区使用标准双方程湍流模型,对倾斜巷道两帮煤壁涌出瓦斯情况下的瓦斯分布与积聚进行数值模拟,研究了风速和倾角不同时风流方向对巷道中瓦斯分布的影响规律。结果表明:倾斜巷道两帮煤壁涌出瓦斯情况下巷道两帮煤壁附近及其上部的两个角上容易积聚高浓度瓦斯,且同一个横断面上部的瓦斯浓度比下部高;风速越大、巷道倾角越大,高浓度瓦斯与空气的交换距离越短,瓦斯与空气充分混合需要的距离越短;下行通风且风速较小时,巷道顶板出现明显的瓦斯逆流现象,逆流区瓦斯浓度远大于瓦斯涌出点下风流一侧的瓦斯浓度,随着风速增大,瓦斯逆流长度逐渐变短。
Based on the basic theory of Computational Fluid Dynamics (CFD), Fluent software was used to discretize the governing equations describing the fluid flow using the control volume method. The flow field was solved using SIMPLEC (a semi-implicit method of coordinated pressure-coupled equations) The standard k-ε wall function method is used to solve the flow near the wall. The standard two-equation turbulence model is used in the turbulent full-scale development zone to simulate the gas distribution and accumulation under the gas outflow of two coal gangue walls. Influence of Wind Direction on Gas Distribution in Roadways with Different Inclination. The results show that high gas concentration tends to accumulate in the two corners near the two coal gangways and the upper part of the coal roadway with two coal gangments gushed out and the methane concentration in the upper part of the same cross section is higher than that in the lower part. , The greater the inclination angle of the roadway is, the shorter the exchange distance of the high-concentration gas and air is and the shorter the distance required between the gas and the air is fully mixed. When the downwind ventilation and the wind speed are small, the obvious gas countercurrent occurs in the roof of the roadway, The gas concentration on the windward side of the gas emission point decreases as the wind speed increases.