NUMERICAL AND EXPERIMENTAL INVESTIGATION OF TRANSIENT PIPE-FLOW

Two mathematical formulations for the computation of transient flow in piping systems are compared with experimental data. The formulations are: a four-equations fluid structure interaction model (FSI) that inc ludes Poisson coupling, and a two-equations model for the fluid. Both models are solved numericaly using the method of characteristics. A pa rtial-closure of a valve located at an intermediate point in a pipelin e is used to create transient flow. The two-equations model computed t he maximum pressure peak satisfactorily but the FSI model gave an over all better simulation. An unsteady-friction model, added to the FSI mo del, did not influence the final results significantly. The experiment al procedures followed to obtain the valve characteristics and the pre ssure history along the pipeline are explained in detail. Excellent nu merical results at the valve are obtained when experimental data is us ed to simulate the time-dependent boundary condition.