Abstract Mixing in a coaxial jet mixer was investigated at variable initial conditions simultaneously using PIV and PLIF methods. Velocity and concentration fields were measured at two spatial resolutions: across the mixer and in a small area at its axis resolving Kolmogorov's scale. Jet exit conditions were modeled by varying flow rate (3⋅103 ≤ Red ≤ 1.78⋅104) and by applying vortex generators (tabs) at the jet exit. The study was executed within a transition flow region. Nevertheless, it is possible to claim that in the self-similarity flow region mean flow parameters do not depend on the initial conditions but turbulence does. The influence of the initial conditions is manifested in turbulent characteristics measured at a high spatial resolution and in the size of fine structures of the studied flows.

中文翻译：

---

射流出口条件对流动精细结构混合统计的影响

摘要 使用 PIV 和 PLIF 方法同时在可变初始条件下研究了同轴喷射混合器中的混合。速度场和浓度场以两种空间分辨率测量：穿过混合器和在其轴上解析 Kolmogorov 尺度的小区域。射流出口条件通过改变流速（3·103 ≤ Red ≤ 1.78·104）和在射流出口处应用涡流发生器（选项卡）来建模。该研究是在过渡流动区域内进行的。然而，可以声称在自相似流动区域中，平均流动参数不取决于初始条件，但湍流会。初始条件的影响体现在以高空间分辨率测量的湍流特性和所研究流动的精细结构的大小上。