TABLE OF CONTENTS Fluid mechanics is a fundamental branch of civil, chemical, and mechanical engineering which deals with the behavior of liquids and gases, particularly while flowing. This chapter provides a brief review of the vocabulary and fundamental equations of fluid mechanics, and reminds the HVAC designer of the scientific principles underlying much of the day-to-day applied science calculations. See Ref. 1 or a fluid mechanics text for additional detail.
Many words are used in fluid mechanics which carry over into thermodynamics and heat transfer. A few of the fundamental terms are defined here for review.
Fluid: A liquid or a gas, a material without defined form which adapts to the shape of its container. Liquids are essentially incompressible fluids. Gases are compressible. Newtonian fluids are those which deform with a constant rate of shear. Water and air are newtonian fluids. Nonnewtonian fluids are those which deform at one rate of shear to a point and then deform at a different rate. Blood and catsup are nonnewtonian fluids.
Density ?: Mass per unit volume, lbm/ft 3.
Viscosity : Resistance to shear, force time/(length) 2.
Pressure P: Force per unit area.
Velocity V: Distance per unit time, ft/min, ft/s.
Laminar flow: Particles slide smoothly along lines parallel to the wall. Resistance to flow is proportional to the square of the velocity.
Turbulent flow: There are random local disturbances in the fluid flow pattern about a mean...
