Effect of nozzle geometries on the propagation of twin jet issuing from nozzles with circle-circle, circle-ellipse, circle-triangle, circle-square, circle-hexagon and circle-star geometrical combinations was investigated for Mach numbers 0.2, 0.4, 0.6 and 0.8. In all the cases, both jets in the twin jet had the same Mach number. All the twin jets of this study are free jets, discharged into stagnant ambient atmosphere. The result of the twin jets issuing from circle-circle nozzle is kept as the reference in this study. For all the twin jet nozzles, the inter nozzle spacing; the distance between the nozzle axes (S) was 20 mm and all the nozzles had an equivalent area of 78.5 mm². Thus for all the cases of the present study, S/D ratio is 2. The results show that the mixing of the combined jet, after the merging point is strongly influenced by the combined effect of the nozzle geometry and jet Mach number. Among the six different twin jet nozzle configuration studied, circle-square combination is found to be the most superior mixing promoter.

中文翻译：

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喷嘴几何形状对双射流特性的影响

研究了马赫数为0.2、0.4、0.6和0.6的马赫数时，喷嘴几何形状对从具有圆形，圆形，椭圆形，圆形三角形，圆形正方形，圆形六角形和圆形星形的喷嘴的双喷流传播的影响。 0.8。在所有情况下，双发喷气机中的两个喷气机都具有相同的马赫数。这项研究的所有双射流都是自由射流，排放到停滞的大气中。本研究以圆喷嘴喷出的双股射流的结果作为参考。对于所有双喷嘴，喷嘴间的间距；喷嘴轴（S）之间的距离为20 mm，所有喷嘴的等效面积为78.5 mm ²。因此，对于本研究的所有情况，S / D比均为2。结果表明，在合并点之后，组合喷嘴的混合受喷嘴几何形状和喷嘴马赫数的组合影响强烈。在研究的六个不同的双喷嘴配置中，发现圆角正方形组合是最优异的混合促进剂。