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为研究围岩温度场变化规律,研制了巷道风流非稳态传热试验系统,并进行了不同进风温度和进风速度下5组试验.基于平板非稳态导热问题,提出了适合判断巷道非稳态传热正规状况阶段新方法.结果表明,巷道非稳态传热存在正规状况阶段,所需无量纲时间即傅里叶数Fo=1.2,对预测温度演变及简化计算有重要意义.将试验数据无量纲化后回归分析,当进风温度在15~25℃时,巷道壁面无量纲温度θ最终稳定在0.4左右.θ与Fo可拟合成线性多项式形式,当次数为4时即有很高精确性;θ与无量纲半径φ可通过对数公式拟合,在正规状况阶段拟合精度高;当风速低于3 m/s时,相对改变进风流温度来说,风速对围岩温度场的影响更大.高温矿井应根据实际情况选择合适的降温方案,以提高方案的经济性和实用性.
In order to study the variation law of surrounding rock temperature field, a series of unsteady heat transfer test system of roadway airflow was developed, and five groups of tests were conducted under different inlet air temperature and inlet air velocity.Based on unsteady heat conduction of flat plate, The results show that the non-steady state heat transfer of the roadway exists in the normal condition stage, and the dimensionless time required, ie Fo = 1.2, is significant for predicting temperature evolution and simplifying the calculation. When the inlet air temperature is in the range of 15 ~ 25 ℃, the dimensionless temperature θ of the wall of the roadway finally stabilizes at about 0.4, θ and Fo can be fitted into linear polynomial form, when the number of times is 4 With high accuracy; θ and the dimensionless radius φ can be fitted by the logarithm formula, the fitting accuracy is high in the normal condition stage; when the wind speed is lower than 3 m / s, relative to change the inlet air temperature, Rock temperature field has a greater impact.High temperature mine should be based on the actual situation to choose the appropriate cooling program to improve the program economy and practicality.