局部通风掘进工作面换热系数分布研究

Study on Distribution of Heat-transfer Coefficient in Heading Face with Auxiliary Ventilation

运用计算流体力学软件FLUENT对局部通风掘进工作面的流场、巷道壁面和风流之间的热量交换进行模拟,获得了局部通风掘进工作面风流速度和温度的分布。根据牛顿冷却定律和换热量与壁面风流速度、摩擦速度以及壁面黏度系数之间的关系,提出了换热系数的计算方法。运用此方法得到了半圆拱形巷道掘进工作面无量纲换热系数的分布,并对不同风量和不同壁面温度情况下无量纲换热系数进行对比分析可知,无量纲换热系数不受巷道风量和壁面温度的影响,只与风筒位置和巷道形状有关。

The distribution of airflow velocity and temperature in a heading face with auxiliary ventilation was obtained by applying Fluent software to simulate the airflow field and the heat exchange between the roadway surface and airflow of the face. A method was put forward to derive the distribution of heat transfer coefficient on roadway surface on the basis of Newton's Cooling Law, the heat quantity transfer from roadway wall to airflow, the friction velocity and viscosity coefficient on wall surface. The distribution of dimensionless heat transfer coefficient was thus obtained with the established method on roadway surface of an semi-circular roadway with auxiliary ventilation. The distribution of dimensionless heat transfer coefficient with airflow quantity and wall surface temperature was analyzed. It was revealed that the distribution of dimensionless heat transfer coefficient has little ependence upon the airflow quantity and wall surface temperature, it only depends on the shape of the roadway and the location of the ventilation duct.