The study of hydraulic transients began with the investigation of the
propagation of sound waves in air, the propagation in shallow water and flow of blood
in arteries. However, none of these problems could solved rigorously until the
development of elasticity and calculus and the solution of parties' differential
equations.
In this chapter, a number of commonly used terms are defined, and a brief history of
the development of the knowledge of hydraulic transients is presented.
The basic water hammer equations for the change in pressure caused by an
instantaneous change in flow velocity are then derived. A description of the
propagation and reflection of waves produced by closing value at downstream and of
a single pipeline is presented. This is followed by a discussion of the classification
and causes of hydraulic transients.
Unsteady flow through closed conduits is described by the dynamic and continuity
equations. The derivation of these equations is presented and methods available for
their solution are discussed.
Methods for controlling transients flow using various devices available to reduce or
to eliminate the undesirable transients. Boundary conditions for these devices will be
developed, which are required for the analysis of a system by the method of
characteristics.
Keywords: Continuity equations, Controlling transients flow, Hydraulic transients,
Propagation and reflection of waves, Water hammer.
