Rocket Propellant Line Waterhammer Transients In a Variable-G Environment
Trey Walters, P.E., Applied Flow Technology - Presented at the Winter Annual Meeting of the American Society of Mechanical Engineers, Dallas, TX, November 1990
Waterhammer pressure transients are generated in liquid-filled pipes when the velocity of the liquid is increased or decreased. Rapid velocity changes (such as an instantaneous valve closure) can lead to very high pipe pressures that may damage the piping system. The fundamental equations of waterhammer can be found in standard references (1, 2. ~. and their solution by the method of characteristics has become a straightforward process when performed on a digital computer.
To simplify the solution, the equations are generally written in terms of piezometric head, which assumes a constant acceleration due to gravity. An application of the equations to waterhammer occurring in a rocket propellant line required that the equations be formulated so as to include varying system acceleration levels. This formulation was incorporated into a computer program, and comparisons with flight data show good agreement.
Edited by: Paul H. Rothe, Creare,Inc.
(Note: this paper was written by an AFT professional prior to the organization of Applied Flow Technology as a company.)