受限空间内甲醇喷雾液滴形成及其爆炸特性

In order to improve the standard testing method of droplet explosion, the droplet formation process and explosion characteristics of methanol were experimentally studied in the 20 L spherical spray testing system, under different ambient pressures, injection pressures and concentrations. The results show that the increasing of injection pressure is more likely to cause the methanol to break into tiny droplets, leading the explosion limit range of methanol droplets broadened. The increasing of ambient pressure would change the explosion limit range of methanol droplet, and can effectively inhibit the explosion accident caused by methanol leakage. When the ambient pressure is 0.1 MPa, and the injection pressure is 2.1 MPa, with the spray concentration of methanol is 356.4 g/m³, the droplet size of the methanol is 2.5 μm. The maximum explosive pressure, the maximum explosion pressure rising rate and the laminar burning rate are the highest at this inflection point. Small droplets (1-15 μm) are more easily ignited by external energy, and the transient physical and chemical reactions are more rapid and violent during explosion. Larger droplets (more than 22 μm) will cause ignition difficult. However, after the ignition is successful, the explosion characteristics increase with the increasing of methanol droplet concentration, showing an approximate linear rule. At this time, the influence of droplet size of methanol on the above explosion characteristics can be neglected. The results could be helpful to understand the law of droplet explosion, improve the testing method and safety design.