The hydrodynamics and local turbulent mixing of parallel multiple liquid jets, submerged in liquid, were investigated by means of experiments and computational fluid dynamics (CFD). A renormalization group (RNG) k-ε turbulence model was used to simulate the flow field. The model was validated experimentally by particle image velocimetry (PIV) measurements. In the converging region adjacent to the nozzle exits, the recirculation region disappears, and there is only ambient fluid entrainment. Different jet arrays were compared to evaluate the effects of the jet spatial arrangement on the hydrodynamics and mixing performance. A shorter mixing length in the merging region suggests that mixing is more efficient in the triple-jet system than in other jet systems. Compared with the jet Reynolds number, the jet spacing plays a more significant role in determining the critical mixing regions, while the linear relationship between them is more sensitive than that for multiple parallel plane jets.

中文翻译：

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水下平行液体射流的流体动力学和局部湍流混合：实验和CFD模拟

通过实验和计算流体动力学（CFD）研究了浸没在液体中的平行多个液体射流的流体动力学和局部湍流混合。重归一化组（RNG）k-ε湍流模型用于模拟流场。该模型已通过粒子图像测速（PIV）测量进行了实验验证。在与喷嘴出口相邻的会聚区域中，再循环区域消失了，仅夹带了周围的流体。比较了不同的射流阵列，以评估射流空间布置对流体力学和混合性能的影响。合并区域中较短的混合长度表明，三重喷射系统中的混合比其他喷射系统中的混合更有效。与射流雷诺数相比，射流间距在确定临界混合区域时起着更重要的作用，而它们之间的线性关系比多重平行平面射流更敏感。