MAE5026 海外专家讲学
Lectures from Oversea Experts
课程学分/学时
Course Credit/Hours
The course is meant to introduce students to open problems to understand basic properties of
turbulent flows for both Eulerian and Lagrangian descriptions, with focus on large- and small-scale
statistics, deviations from Gaussian behavior, direct and inverse cascades. Finally, we shortly present
a couple of applications to Helical and Rotating flows in finite or infinite volumes.
本课程旨在向学生介绍欧拉和拉格朗日描述的湍流中的开放性问题,重点是不同尺度的统计特
性,直接和反向级联。最后,我们简要介绍有限或无限体积中的螺旋和旋转流动的几个应用。
Introduction to statistical description of Turbulent flows: real space,
Fourier space and scale-filtered representation.
Introduction to statistical description of Turbulent flows: ergodicity,
definitions of spectra, flux and high order statistics (Flatness, Skewness)
Multi-scale statistics: non-Gaussian statistics, intermittency, sub-grid
energy flux, multifractal phenomenology (Eulerian)
Lagrangian turbulence: tracers, inertial particles, self-propelling particles.
Preferential concentration and temporal statistical properties.
Homogeneous and Isotropic flows: state of the art in 3d. Direct energy
cascade. K41 Theory and corrections to it.
Homogeneous and Isotropic flows: state of the art in 2d. Inverse energy
cascade and direct enstrophy cascade. Kraichnan-Batchelor theory.
Helical properties in 3d flows. Eulerian and Lagrangian (helicoids).
Effects of Rotation: transition from direct to split energy cascades.