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基于Fluent软件模拟了柱型、扇型、锥型和混合型喷嘴真空喷射射流雾化过程,研究了喷嘴结构对动压力转换、射流速度和喷嘴出口湍动能的影响。结果表明,锥型喷嘴动压力较大,可提高静压能转换效率;扇型和锥型喷嘴喷射束宽度较大,利于大面积喷射成膜;扇型喷嘴易形成空化,出口湍动能较大,有助于液滴初次雾化破碎,而混合型喷嘴的空化层厚度最小,湍流区域最大。通过分析雾化锥角与喷嘴流量系数,发现扇形和锥直形喷嘴具有较大雾化锥角,但流量系数较小喷嘴压力损失较大;喷嘴直线段会提高锥型喷嘴雾化锥角和喷嘴出口湍动能,并使扇型喷嘴的流量系数增大,但射流雾化锥角减小。最后,本文尝试构建了真空喷射射流雾化数学模型。
Based on the Fluent software, the vacuum jet jet atomization process of the column, the fan, the cone and the mixed nozzle was simulated and the influence of the nozzle structure on the dynamic pressure conversion, jet velocity and the turbulent kinetic energy at the nozzle exit was studied. The results show that the dynamic pressure of cone nozzle can increase the conversion efficiency of static pressure energy. The width of the spray beam in fan-shaped and cone-shaped nozzles is larger, which is good for large area spray film formation. Large, helps the initial droplet atomization broken, while the mixed nozzle minimum cavitation layer thickness, maximum turbulence area. By analyzing the atomizer cone angle and the nozzle flow coefficient, it is found that the fan-shaped and the cone-shaped nozzle have a larger atomization cone angle, but the smaller the flow coefficient is, the nozzle pressure loss is larger; the nozzle straight line segment will increase the cone nozzle cone angle and The jet outlet turbulent kinetic energy, and fan-shaped nozzle flow coefficient increases, but the jet atomization cone angle decreases. Finally, this paper attempts to build a mathematical model of jet vacuum atomization.