标题： 关于墙壁如何影响耗散的间歇性 显示英文标题

标题： On how walls shape dissipation intermittency

摘要： 能量耗散的间歇性长期以来通过均匀各向同性湍流中的高阶矩进行研究，但当边界效应被明确包含时则研究较少。 在这里，我们推导了壁面受限流动中耗散矩的两个基本雷诺数标度表达式——一个在边界效应较弱的外区，另一个在边界效应较强的壁面附近——并通过直接数值模拟支持这些表达式。 外区的耗散矩遵循与速度结构函数异常标度相关的通用幂律。 相反，壁面附近的矩遵循有界缺陷定律，导致没有间歇性的有限渐近极限。 对于非常大的雷诺数，外区的预测表明相对于壁面的耗散而言耗散趋于消失，突显了固体边界在生成翁萨格型奇异性中的必要性。 显示英文摘要

摘要： Intermittency of energy dissipation has long been studied via high-order moments in homogeneous and isotropic turbulence, but not much where the boundary effects are explicitly included. Here, we derive two fundamental Reynolds number scaling expressions for dissipation moments in wall-bounded flows -- one in the outer region where the boundary effects are weak and the other close to the walls where those effects are strong -- and support these expressions by direct numerical simulations. Dissipation moments in the outer region follow universal power laws with exponents linked to anomalous scaling of velocity structure functions. In contrast, moments near the wall follow a bounded defect law, leading to a finite asymptotic limit without intermittency. For very large Reynolds numbers, the outer proposal predicts vanishing dissipation compared to that on the wall, highlighting the need for solid boundaries in generating Onsager-type singularities.