泡沫胶体三联发泡器的管流特性与优化

Pipe flow characteristics and optimization of foam colloid triplet foamer

泡沫胶体是矿井火灾防治的有效手段之一,泡沫胶体三联发泡器的设计合理与否直接影响到泡沫胶体的实际性能。采用VOF模型模拟了发泡器内部氮气与浆液的实际混合过程,分析了发泡器管流特性,对比了氮气入口管数量和位置等结构参数对发泡系统的混合效果,讨论了浆液流量、氮气流量和调节头位置等操作参数对发泡系统的混合效果,得出优化的发泡器结构参数和操作参数。模拟结果显示:氮气入口管数量和位置对发泡系统混合效果的影响较为复杂,且混合效果还与调节头位置有关;相比于不同分布下的6个入口管,氮气采用9个入口管输入时可将平均混合程度提升1.7%~10.4%,更利于泡沫胶体在发泡器中的混合与制备;此外,基于发泡器中浆液流量、氮气流量和调节头位置的三因素五水平正交试验分析发现浆液流量和氮气流量对发泡系统混合效果的影响显著性分别是调节头位置的4.04和3.68倍;泡沫胶体三联发泡器的最优工况为浆液流量20 m^(3)/h、氮气流量1200 m^(3)/h、调节头处于中后位置。

Foam colloid is one of the effective means of fire prevention and control in mine.Whether the design of foam colloid triplet foamer is reasonable or not directly affects the actual performance of foam colloid.By means of VOF model to simulate the internal nitrogen foam generator and slurry mixing process,we analyzed the characteristics of foam generator tube flow,compared the mixing effects of structural parameters such as the number and position of nitrogen inlet pipe on foaming system,discussed the mixing effects of operating parameters such as slurry flow rate,nitrogen flow rate and position of regulating head on foaming system,and obtained the optimized structural and operating parameters of bubbler.The simulation results show that the number and position of nitrogen inlet tubes have a complex effect on the mixing effect of the foaming system,and the mixing effect is also related to the position of regulating head.Compared with the 6 inlet tubes in different positions,the average mixing degree of nitrogen with 9 inlet tubes can be increased by 1.7%to 10.4%,which is more conducive to the mixing and preparation of foam colloid in the foamer.In addition,based on the three-factor and five-level orthogonal test of slurry flow,nitrogen flow and adjusting head position in the foamer,the significance of slurry flow and nitrogen flow on the mixing effect of foaming system is 4.04 and 3.68 times that of the adjusting head position,respectively.The optimal working conditions of the foam colloid triplet foamer for fire prevention are the slurry flow rate of 20 m^(3)/h,nitrogen flow rate of 1200 m^(3)/h,and the regulating head in the middle and rear position.