Pressure swirl atomizers are widely used in gas turbine combustor; this paper is aimed at researching the effect of low ambient pressure (0.1 MPa to 0.01 MPa, lower than an atmosphere) on the spray cone angle of pressure swirl atomizer. The spray angle is captured by high-speed photography; then, an image post program is used to process the spray angle magnitude. A mathematical model of a single droplet’s movement and trajectory based on force analysis is proposed to validate the spray angle variation. The maximum variation of the spray cone angle, which is observed when fuel supply pressure drop through the atomizer is 1 MPa as the ambient pressure decreases from 0.1 MPa to 0.01 MPa, is found to be 23.9%. The experimental results show that the spray cone angle is expected to increase with the ambient pressure decrease; meanwhile, mathematical results agree well with this trend.

中文翻译：

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低环境压力对压力旋流雾化器喷雾锥角的影响

压力旋流雾化器广泛应用于燃气轮机燃烧室；本文旨在研究低环境压力（0.1 MPa至0.01 MPa，低于一个大气压）对压力旋流雾化器喷雾锥角的影响。喷雾角度由高速摄影捕捉；然后，使用图像后期程序来处理喷雾角度大小。提出了基于力分析的单个液滴运动和轨迹的数学模型来验证喷雾角度变化。当环境压力从 0.1 MPa 降低到 0.01 MPa 时，通过雾化器的燃料供应压力下降为 1 MPa 时观察到的喷雾锥角的最大变化为 23.9%。实验结果表明，随着环境压力的降低，喷雾锥角有望增加；同时，