EFFECT OF TEMPERATURES ON FLAME PROPAGATION OF DIETHYL ETHER SPRAY EXPLOSION

Abstract

The study aims to identify the flame propagation characteristics in the diethyl ether (DEE) spray explosion. Different ambient and material temperatures' effect on flame propagation and structure was investigated in a 20-L explosion vessel. Greyscale histograms are obtained from the high-speed images to distinguish the combustion and explosion zones. With the ambient temperature increased, the combustion duration showed a trend of first decreasing, then increasing, and then decreasing again. The combustion zone first increased and then decreased. The explosion duration showed an overall decreasing trend. The explosion duration was longer than the combustion duration, ranging from 152.75 to 307 ms. When the ambient temperature was 308.15 K, the combustion duration reached its minimum value of 13.25 ms, and the equivalent radius of the combustion zone reached its maximum value of 52.89 mm. With the increase in material temperature, both the combustion and explosion durations showed a trend of first decreasing and then increasing, with combustion durations ranging from 12.42 to 16.25 ms and explosion durations ranging from 106 to 117.5 ms, respectively. The difference in the equivalent radius of the combustion zone under different material temperatures was slight, and the influence of material temperature on the development of the combustion zone was relatively small. When the material temperature was 308.15 K, th combustion zone expansion rate reached its maximum value of 10.20 m/s, and the explosion zone expansion rate reached its maximum value of 13.36 m/s. The flame instability and flame propagation velocity in the explosion zone were both greater than in the combustion zone.