This paper experimentally and numerically investigates the water hammer phenomenon in serially connected steel HDPE pipes with different diameters. The aim of laboratory tests was to obtain time history pressure head at downstream end pipeline system. Transient were conducted on seven system configurations. experimental results show that despite significantly smaller diameter pipe compared pipe...

A new type of pulsed water jet, which uses principles of self-resonance to create pressure fluctuations, is now being developed. The advantages of pulsing to improve the erosive action of a jet—by interrupting the flow, hence using the water hammer impact stress created by each individual slug—have long been appreciated by the users of water jets for cutting and cleaning applications. Of severa...

A hammer-string interaction for bass notes is investigated and the problem what can cause the hammer to rebound is clarified. For a linear elastic hammer interacting with a long flexible string the exact solution of the equation describing the hammer motion is derived. It was shown that in some cases no reflected wave is needed to assist the hammer for going away from the string. The numerical ...

This paper focuses on the formulation and assessment of a second-order accurate Finite Volume (FV) shock-capturing scheme for simulating two-phase water hammer flows. The two-phase flow model is based on the single-equivalent fluid concept. The accuracy and numerical efficiency of the proposed scheme is compared to the fixedgrid MOC scheme with space-line interpolation. The results show that th...

Vertebrobasilar dolichoectasia is a clinical entity associated rarely with obstructive hydrocephalus. We present a 48-year old male with a profound dilatation of the ventricular system due to a dolichoectatic basilar artery, as appeared in imaging studies. The patient suffered from longstanding hydrocephalus and presenile dementia. The underlying mechanism for obstructive hydrocephalus due to v...