Fluid Mechanics for Chemical Engineers: with Microfluidics, CFD, and COMSOL Multiphysics 5

Chapter 6. Solution of Viscous-Flow Problems

6.1 Introduction

THE previous chapter contained derivations of the relationships for the conservation of mass and momentum—the equations of motion—in rectangular, cylindrical, and spherical coordinates. All the experimental evidence indicates that these are indeed the most fundamental equations of fluid mechanics and that in principle they govern any situation involving the flow of a Newtonian fluid. Unfortunately, because of their all-embracing quality, their solution in analytical terms is difficult or impossible except for relatively simple situations. However, it is important to be aware of these “Navier-Stokes equations” for the following reasons:

1. They lead to the analytical and exact solution ...