Water Hammer

Water Hammer with Column Separation:

Column separation refers to the breaking of liquid columns in fully filled pipelines. This may occur in a water hammer event when the pressure drops to the vapor pressure at specific locations such as closed ends, high points or knees (changes in pipe slope). A vapor cavity, driven by the inertia of the parting liquid columns, will start to grow. The cavity acts as a vacuum, a low-pressure poin...

Multiple Scales Analysis of Water Hammer Attenuation

A multiple scales analysis is used to construct a uniformly accurate approximation to water hammer pressure wave attenuation that is initiated by a sudden valve opening. The method of analysis is well suited to the study of a water hammer that possesses several time scales and is applied to a mild generalization of the classical equations. It should prove useful for finding attenuation curves w...

Water hammer dissipation in pneumatic slug tests

Godunov-type Solutions for Two-phase Water Hammer Flows

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 Induced Hydrocephalus: the Water-Hammer Effect

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...