Study on combustion and flame merging characteristics of two n-heptane line fires under wind speed, spacing, and groove width

Abstract

This paper studied the effects of wind speed, spacing and groove width on the combustion and flame merging characteristics of two n-heptane line fires. The experimental results show that the range of intermittent merging stage will increase with groove width; the greater the wind speed, the greater the probability of merging. At the non-merging stage, the influence of wind speed on the flame merging probability can be ignored. Under the influence of wind speed, mass loss rate per unit area, ??, of the downstream pool fire is greater than that of the upstream pool fire, at the stages of fully merging and intermittent merging. While when the flame spacing increases to the non-merging stage, ?? of the upstream pool fire begins to be gradually greater than that of the downstream pool fire. On the other hand, the downstream flame ?? increases firstly and then decreases, while the upstream flame ?? shows an increasing trend, with spacing distance. The smaller the groove width, the greater the value of ?". When the spacing is 0, ?? is the smallest. It is found that with the increase of spacing, the flame length under all tested conditions increases firstly and then decreases, and the flame inclination angle decreases firstly and then increases.