高温高湿巷道内不稳定换热系数影响因素分析及模型建立

Analysis on influencing factors of unstable heat transfer coefficient in high temperature and high humidity roadway and model establishment

为研究高温高湿巷道不稳定换热系数的变化规律,采用Fluent软件对高温高湿巷道内的热湿交换进行数值模拟,通过单因素和正交模拟实验探讨风流温度、风流速度、岩石导热系数、原岩温度以及巷道当量直径对高温高湿巷道不稳定换热系数的影响。研究结果表明:高温高湿巷道不稳定换热系数随时间的变化规律与普通巷道一致,均与通风时间呈负相关,但通风时间为1 a的高温高湿巷道不稳定换热系数较普通巷道增加了12.5%。通过单因素分析得到风流速度、岩石导热系数和当量直径与不稳定换热系数呈正相关。通过极差分析得到各因素对不稳定换热系数的影响程度为:岩石导热系数>当量直径>风流速度>风流温度>原岩温度。利用SPSS软件对正交实验数据进行拟合,建立不稳定换热系数的计算模型,拟为高温高湿巷道内热负荷计算及井下风温预测提供参考。

In order to study the variation law of unstable heat transfer coefficient in high temperature and high humidity roadway,the heat and moisture exchange in high temperature and high humidity roadway was numerically simulated by FLUENT software.Through the single factor and orthogonal simulation experiments,the influence of air flow temperature,air flow velocity,rock thermal conductivity,raw rock temperature and roadway equivalent diameter on the unstable heat transfer coefficient in high temperature and high humidity roadway was discussed.The results showed that the variation law of unstable heat transfer coefficient in high temperature and high humidity roadway with time was consistent with that in ordinary roadway,both of which were negatively correlated with the ventilation time,but the unstable heat transfer coefficient in high temperature and high humidity roadways with the ventilation time of one year was 12.5%higher than that in ordinary roadway.Through the single factor analysis,it was found that the air flow velocity,thermal conductivity of surrounding rock and equivalent diameter were positively correlated with the unstable heat transfer coefficient.Through the range analysis,the influence degree of each factor on the unstable heat transfer coefficient was as follows:rock thermal conductivity>equivalent diameter>air flow velocity>air flow temperature>raw rock temperature.The orthogonal experimental data were fitted by SPSS software,and a calculation model of unstable heat transfer coefficient was established,which provides reference for the calculation of heat load in high temperature and high humidity roadway and the prediction of underground air temperature.