Abstract:

In this paper,the diffused combustion flame linearly moving in different conditions was analyzed by experimentsand was numerically simulated and compared using the software of Fluent.The results show that themovement of fire greatly influences the combustion flame. For example,at a wind speed of 0m/s,the flame movesto the contrary direction of the fire source movement,with a deflection angle increasing with the fire speed.At thefire speed of 0. 36,0. 44 and 0. 55m/s,the flame deflection angle respectively reaches 36°,47°and 60°.Underthe action of wind and car movement with the same relative speed,the flames deflect to the same direction but exhibitdifferent shapes,and the cobbustion flame in a absolute rest condition is of a lower combustion temperaturebecause it dissipates more heat energy.Moreover,it is found that,as compared with the combustion flame in absoluterest condition,the flame in relative rest condition has a shape deviation to the contrary movement direction ofthe fire source and a higher combustion temperature.According to the above-mentioned statements,it is concludedthat the diffusion combustion flame with mobile source cannot be simply analyzed with the concept of relative motiondue to the great difference in the intrinsic influence and the flame shape.

Key words: mobile fire source, diffusion combustion, flame shape, relative rest, numerical simulation