Chapter 2. Hydrodynamic Approach Available to Purchase

In Chapter 1, we established the Boltzmann equation, which is at the heart of kinetic theory. Such a kinetic description is indeed of great precision in the sense that it introduces the notion of distribution and, in doing so, makes it possible to describe the differences (of velocity or energy) between the different particles that constitute the system. We can say that it is a mesoscopic description, that is, intermediate between a microscopic description (i.e. based on the individual equations of motion of each particle) and a macroscopic description. This chapter presents, precisely, such a macroscopic approach, called hydrodynamic or fluid.