Experimental investigation of laminar water hammer in helical pipe considering pipe wall viscoelasticity

The water hammer phenomenon is of great interest in many applications, mainly because of its devastating impacts on the hydraulic systems. In this study, the water hammer phenomenon in helical pipes with the rigid and viscoelastic wall behavior is studied through an experimental investigation. To this end, a setup consisting of a pressurized tank, copper and polyethylene tubes, pressure transmitter, and solenoid valve is built to investigate the effect both in tubes with rigid and viscoelastic wall behavior. The flow in the system is controlled in a way that it remains within the laminar range of the flow in coiled pipes. According to the results obtained from tests in copper pipe, pressure wave attenuation is more significant in this system which the underlying reason for this situation is the combination of coiling effect and losses caused by small pipe diameter. This attenuation becomes further significant in PE pipes as a result of the pipe-wall viscoelasticity.

Keywords:

Water hammer , Helical pipe , Experimental study , Transient flow , Pipe-wall viscoelasticity