Chapter 6

Viscous flow

The Navier-Stokes equations are derived from scratch in two pages, and various fluid themes are then touched on: material derivatives, boundary conditions (no slip, normal stress with surface tension, kinematic); vorticity, Reynolds number, instability and turbulence, lubrication theory, droplet dynamics, and their application to ice sheets (which are droplets with accumulation). The notes, and also some of the exercises, have further discussion, particularly on the no slip condition and surface tension.