N_(2)-阻化细水雾装置研发及运行参数试验研究

Experimental Study on the Development and Operating Parameters of N_(2)-inhibited Water Mist Device

N_(2)-阻化细水雾的雾化效果直接影响着其在火区的灭火降温效果。在N_(2)-阻化细水雾气液两相流雾化理论分析的基础上,研究分析了不同气压、液压以及添加阻化剂等正交试验条件下,细水雾的粒径分布情况和雾化装置的最佳运行工况条件。结果表明:(1)在水压与气压正交试验中,水压与气压的升高,细水雾粒径整体越来越小,但在相同流量条件下,水压的升高会导致雾化效果不理想,在水压为0.2 MPa~0.6 MPa、气压为0.8 MPa~1.25 MPa的条件,细水雾的粒度分布较小;(2)细水雾粒径D90和D50在不同的气液压力比条件下呈现出一致的变化趋势,但在某一临界值后变化速率较缓慢,在气压为1 MPa~1.25 MPa、气液压力比为3~4时,细水雾粒径为30μm~50μm;(3)在水压一定条件下,是否含有阻化剂的细水雾的粒径均随气压升高而逐渐减小,C1组复合阻化剂雾化效果较为理想,最佳工况条件为:气压为0.8 MPa~1.0 MPa;气液压力比为3~4;复合阻化剂是氯化镁∶磷酸二氢铵=3∶2,浓度为20%。

The atomization effect of N_(2)-inhibited water mist directly affects its extinguishing and cooling effect in the fire area. Based on the theoretical analysis of gas-liquid two-phase flow atomization of N_(2)-inhibited water mist, the particle size distribution and the optimal operating conditions of the water mist under different orthogonal test conditions such as air pressure, hydraulic pressure and addition of inhibitors were studied and analyzed. The results are concluded as follows. Firstly, in the orthogonal tests of water pressure and air pressure, with the increase of water pressure and air pressure, the overall particle size of the water mist is getting smaller and smaller, but under the same flow condition, the increase of water pressure will cause the atomization effect to be unsatisfactory. The particle size distribution is small under 0.2~0.6 MPa of water pressure and 0.8~1.25 MPa of air pressure. Secondly, the D90 and D50 particle sizes of water mist show a consistent change trend under different gas-liquid pressure ratio conditions, but the change rate becomes slow after a certain critical value. When the air pressure is 1~1.25 MPa and the gas-liquid pressure ratio is 3∶4, the particle size of the water mist is 30~50 μm. Thirdly, under a certain of water pressure, whether it contains inhibitors, the particle size of the water mist decreases gradually with the increase of air pressure. The atomization effect of the composite inhibitor of group C1 is ideal. The best working conditions are air pressure of 0.8~1.0 MPa, gas-liquid pressure ratio of 3∶4, composite inhibitor of magnesium chloride: ammonium dihydrogen phosphate=3∶2, and concentration of 20%.