AI 中文总结
研究壁面湍流中长条纹再生等问题，通过实验和模拟发现长条纹初始增长与平均剪切力和长横向流速有关，特定模拟中湍流在部分阻尼下能持续且恢复，给出相关模拟及能量平衡解释，支持新的壁面湍流模型。
AI 中文摘要
对原本已衰减的长条纹再生的流动实验表明，其初始增长是由于平均剪切力与即使条纹衰减仍存在的长横向流速（滚轴）相互作用。更令人惊讶的是，在仅阻尼长滚轴而长条纹仍保留的模拟中，湍流也持续存在，且去除阻尼时这些流动也能恢复。最后给出了条纹和滚轴长度大于$\lambda_x^+ \approx 600$都被阻尼的模拟。它们能存活并再生，还提供了基于能量平衡的解释。与包含无限长结构的经典最小通道相反，这些新流动不包含长于阻尼波长的特征，并支持壁面湍流仅取决于几何长宽比为单位量级过程的模型。
英文摘要
Experiments on the regeneration of long streaks in flows in which they had originally been damped show that their initial growth is due to the interaction of the mean shear with long cross-flow velocities (rollers) that remain even when the streaks are damped. More surprisingly, turbulence also persists in simulations in which only the long rollers are damped while long streaks remain, and these flows are also able to recover when the damping is removed. Finally, simulations are presented in which both streaks and rollers longer than $λ_x^+ \approx 600$ are damped. They survive and regenerate, and an interpretation in terms of their energy balance is provided. In contraposition to the classical minimal channels, which include infinitely long structures, these new flows do not contain features longer than the damping wavelength, and support a model in which wall turbulence only depends on processes for which the geometric aspect ratio is of order unity.
