The conditions for merging two liquid sheets in a coaxial pressure-swirl external mixing injector were assessed experimentally and numerically. Fast imaging was employed based on the backlighting technique to experimentally investigate the behavior of the exit liquid sheet. The simulation was also carried out using a volume of fluid model considering two-dimensional axisymmetric swirl conditions. Performance characteristics including discharge coefficient, sheet angle, and sheet pattern at different injection pressures were assessed experimentally and by simulation for separate and simultaneous spraying conditions. To study the merging condition, the gas phase pressure field just downstream of the injector exit was numerically investigated separate and simultaneous results show that the lowest gas pressure occurs in the region inside the liquid cone produced. The larger the diameter of the injector outlet, the greater the volume of the hollow cone and the smaller the amount of this vacuum. When the internal and external injectors worked simultaneously, three areas were distinguished: the inner space of the internal injector, the space between the two liquid sheets, and the outer space of the external injector. The largest pressure gradients in the gas pressure occurred in the space between the two liquid sheets. By increasing the injection pressure of the external injector, the static pressure between the two sheets decreased and reached the pressure required to merge the two sheets, thus, the two liquid sheets can merge.

中文翻译：

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合并来自同轴压力旋流喷射器的锥形液体板

通过实验和数值评估了在同轴压力旋流外部混合注射器中合并两个液体层的条件。采用基于背光技术的快速成像来实验研究出口液层的行为。还使用考虑二维轴对称涡流条件的流体体积模型进行了模拟。通过实验和模拟单独和同时喷涂条件来评估不同喷射压力下的性能特征，包括流量系数、片材角度和片材图案。为了研究合并条件，对喷射器出口下游的气相压力场进行了单独和同步的数值研究，结果表明最低气压出现在所产生的液锥内部的区域。喷射器出口直径越大，空心锥体的体积就越大，这种真空量就越小。当内、外喷射器同时工作时，分为三个区域：内喷射器的内部空间、两液片之间的空间和外喷射器的外部空间。气体压力中最大的压力梯度出现在两个液体层之间的空间中。通过增加外部注射器的注射压力，两片材之间的静压降低并达到合并两片材所需的压力，因此，