A companion paper by Hecht et al. (2020, https://doi.org/10.1002/2014JD021833) describes high‐resolution observations in the hydroxyl (OH) airglow layer of interactions among adjacent Kelvin‐Helmholtz instabilities (KHI). The interactions in this case were apparently induced by gravity waves propagating nearly orthogonally to the KHI orientations, became strong as Kelvin‐Helmholtz (KH) billows achieved large amplitudes, and included features named “tubes” and “knots” in early laboratory KHI studies. A numerical modeling study approximating the KHI environment and revealing the dynamics of knots and tubes is described here. These features arise where KH billows are misaligned along their axes or where two billows must merge with one. They bear a close resemblance to the observed instability dynamics and suggest that they are likely to occur wherever KHI formation is modulated by variable wind shears, stability, or larger‐scale motions. Small‐scale features typical of those in turbulence develop in association with the formation of the knots and tubes earlier and more rapidly than those accompanying individual billows, supporting an earlier conjecture that tubes and knots are commonly major sources of intense turbulent dissipation accompanying KHI events in the atmosphere.

中文翻译：

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安第斯激光雷达天文台的中层开尔文-亥姆霍兹巨浪相互作用和不稳定性：2.建模和解释

Hecht等人的伴随论文。（2020，https://doi.org/10.1002/2014JD021833）描述了在相邻开尔文-亥姆霍兹不稳定性（KHI）之间相互作用的羟基（OH）气辉层中的高分辨率观测结果。这种情况下的相互作用显然是由几乎垂直于KHI方向传播的重力波引起的，随着开尔文-亥姆霍兹（KH）的波涛达到大幅度而变得很强，并且在早期的实验室KHI研究中包括名为“管”和“结”的特征。这里描述了一个近似KHI环境并揭示结和管动力学的数值模型研究。这些特征出现在KH波浪沿其轴未对齐或两个波浪必须与一个合并的情况下。它们与观察到的不稳定性动力学非常相似，并表明它们很可能发生在由可变风切变，稳定性或较大尺度运动调节的KHI形成的任何地方。湍流中典型的小尺度特征与结节和管的形成有关，比伴随单个涛动的结节更早，更迅速地发展，这支持了更早的推测，即管结通常是伴随KHI事件而强烈湍流消散的主要来源。气氛。