ABSTRACT
Th e equations of change are the result of applying three physical laws to an open system. Th e laws are the law of conversation of mass, Newton’s second law of motion, and the fi rst law of thermodynamics. Th e resulting partial diff erential equations are referred to as the continuity equation, the equations of motion or the Navier-Stokes equations, and the general energy equation. Th e conservation laws are applied to an open system, a fi nite control volume fi xed in space with material fl owing through it is used, or they are applied to an arbitrary control volume moving with the mass average velocity of the fl uid. Unless specifi cally stated to the contrary, all of the fl ows described in this chapter are assumed to be laminar. Th e treatment of turbulent fl ow is described in Chapters 4 and 5.
