Water Hammer in Viscoelastic pipes - The effect of junctions - First Results

Fluid-structure interaction is an important topic for modeling water hammer pressure surges in piping systems. Even if recently, in technical literature there are many interesting contributes on water hammer propagation in viscoelastic pipes, little attention has been devoted so far to the modellization of transmission and reflection of pressure surges at junctions of pipes as well as on the effect of bound condition of the pipe. In order to investigate such effects a test facility was built in the Laboratorio di Ingegneria delle Acque (LIA) of University of Cassino. The model has a scheme comparable to irrigation systems and it is made with HDPE pipes. Moreover bound conditions of the pipes can be changed using a movable anchors system and simultaneous measurements of pressure and flow are available at different times. In the paper first experimental results are reported and a analysis of them is presented.