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在湍流强迫对流换热系数经验计算公式基础上,结合矿井瓦斯爆炸实际情况以及前人所进行的管道瓦斯爆炸所测得的实验数据,进行了矿井瓦斯爆炸情况下影响火焰波和围岩对流换热系数的相关因素的分析和计算,确定出了这些影响因子的取值范围。对不同情形下的瓦斯爆炸后的巷道对流换热系数进行了计算,得出:对流换热系数在l/D≤28范围内逐渐增加,在28≤l/D≤52范围内变化幅度很小,52≤l/D≤70范围内迅速并在l/D=70处达到最大值,然后随着火焰波的传播距离增加缓慢减小,直至对流换热现象结束。同时可以看出,对流换热系数随着巷道当量直径的减小而增大。对流换热系数最大值在112.3～158.3W/(m2·K)之间,最小值在13.6～21.6W/(m2·K)之间。
Based on the empirical formula of forced convection heat transfer coefficient of turbulent flow and the experimental data measured by gas explosion in the mine and previous gas explosion, the paper analyzes the influence of the flame wave and the surrounding rock convection The analysis and calculation of the related factors of the thermal coefficient have determined the range of the values of these influencing factors. The calculation of the convective heat transfer coefficient of roadway after gas explosion in different situations shows that the convective heat transfer coefficient increases gradually in the range of l / D≤28 and the variation range is small in the range of 28≤l / D≤52 , 52≤l / D≤70 and reach the maximum at l / D = 70, then decrease slowly as the flame propagation distance increases until the convection heat transfer is completed. At the same time, it can be seen that the convective heat transfer coefficient increases as the equivalent diameter of the roadway decreases. The maximum convective heat transfer coefficient is between 112.3 ~ 158.3W / (m2 · K) and the minimum value is between 13.6 ~ 21.6W / (m2 · K).