This paper investigates the effects of the pipe-wall viscoelasticity on water-hammer pressures. A large-scale pipeline apparatus made of polyvinyl chloride (PVC) at Deltares, Delft, The Netherlands, has been used to carry out waterhammer experiments. Tests have been conducted in a reservoir-pipe-valve system with a 275.2 m long DN250 PVC pipeline. Rapid closure of a manually operated ball valve at the downstream end generated water hammer. Computed results are compared with experimental runs. Calibrated creep functions have been obtained using optimization in conjunction with an inverse hydraulic transient solver and these are used in the simulations. It is shown that the incorporation of both unsteady skin friction and viscoelastic pipe wall mechanical behaviour in the hydraulic transient model contributes to a favourable fitting between numerical results and observed data.
|Title of host publication||Proceedings of the 4th IAHR International Meeting on Cavitation and Dynamic Problems in Hydraulic Machinery and Systems (Belgrade, Serbia, October 2011)|
|Editors||A. Gajic, M. Benisek, M. Nedeljkovic|
|Publication status||Published - 2011|