Coupled Analysis of Fluid Transients and Structural Dynamic Responses in Pipelines by MOC-FDM

Water hammer is a type of transient flow in pipelines which may in general be produced due to valve
closure or sudden shut down of pumps. Transient flow creates sudden variation in the velocity and
pressure of fluid flow in the pipelines which in effect may induce some dynamic vibrations in the
structure of pipe. Furthermore, such structural vibrations can affect the fluid flow. Taking into account
them is necessary for modeling of fluid-structure interaction. In this paper the fluid-structural
interaction (FSI) of water hammer in pipeline systems are investigated. Two sets of hydraulic and
structural equations with common variables have been numerically analyzed through MOC-FDM
simultaneous solving process which has been prepared by a computer-assisted program. Some
examples have been solved by this method, with satisfactory results. This indicates that fluid-structure
interaction can have critical effect on the value of fluid pressure.