Easy turbulence

This is an introductory course on fully developed turbulence. It discusses: in Lecture 1: the Navier Stokes equations, existence of solutions, statistical description, energy balance and cascade picture; in Lecture 2: the Kolmogorov theory of three-dimensional turbulence versus intermittency, the Kraichnan-Batchelor theory of two-dimensional turbulence; in Lecture 3: the Richardson dispersion law and the breakdown of the Lagrangian flow; in Lecture 4: direct and inverse cascades and intermittency in the Kraichnan model of passive advection.