Physical Understanding of Sudden Pressurization of Pipe Systems with Entrapped Air: Energy Auditing Approach
@article{Malekpour2016PhysicalUO, title={Physical Understanding of Sudden Pressurization of Pipe Systems with Entrapped Air: Energy Auditing Approach}, author={Ahmad Reza Malekpour and Bryan W Karney and Johnathan Nault}, journal={Journal of Hydraulic Engineering}, year={2016}, volume={142}, pages={04015044} }
AbstractA global energy-auditing approach is used to describe the complex transient flow associated with sudden pressurization of a confined pipe system containing entrapped air pockets. The key concept is that the greatest pressures following pressurization are directly related to the amount of energy absorbed by the air pockets. The energy approach leads to an insightful understanding of the transient pressurization event, one that clarifies the underlying physics and that better explains…
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References
SHOWING 1-10 OF 21 REFERENCES
Understanding of the Risks of High Pressures Following Rapid Pressurization in Pipelines Containing Entrapped Air Pockets: A Novel Energy Auditing Approach
- Engineering
- 2014
Rapid pressurization of liquid pipelines containing entrapped air may result in extreme overpressures. Both experimental and numerical studies have shown that the magnitude of the induced pressure…
Influence of entrapped air pockets on hydraulic transients in water pipelines
- Engineering, Physics
- 2011
The pressure variations associated with a filling undulating pipeline containing an entrapped air pocket are investigated both experimentally and numerically. The influence of entrapped air on…
Models for Analysis of Water Hammer in Piping With Entrapped Air
- Physics, Engineering
- 2002
Water hammer transients in a pipe line with an entrapped air pocket are analyzed with three one-dimensional models of varying complexity. The most simple model neglects the influence of gas-liquid…
Influence of Liquid Length Variation in Hydraulic Transients
- Engineering, Physics
- 1992
When a problem of hydraulic transients with entrapped air in pipelines and/or with water‐column separation is tackled, the variation of the length of the liquid column is not usually taken into…
Pressure Surges Following Sudden Air Pocket Entrapment in Storm-Water Tunnels
- Engineering
- 2012
AbstractDeep storm-water storage tunnels may undergo pressurization during intense rain events. In the process, air pockets may become entrapped and pressurized, causing significant flow changes.…
Simulation of Flow Transients in a Water Filling Pipe Containing Entrapped Air Pocket with VOF Model
- Engineering, Physics
- 2011
Abstract: he pressure within an entrapped air pocket in a filling pipeline without air release is investigated both experimentally and numerically. Volume of Fluid (VOF) model is introduced to…
Rigid-plug elastic-water model for transient pipe flow with entrapped air pocket
- Engineering
- 2011
Pressure transients in a rapidly-filling pipe with an entrapped air pocket are investigated analytically. A rigid-plug elastic-water model is developed by applying elastic-water hammer to the…
Pressure Transients due to Compression of Trapped Air in Rapidly Filling Sewer Storage Tunnels
- Engineering
- 2012
Increasing numbers of lines of evidence indicate that entrapment of large pockets of air during the rapid filling of stormwater and combined sewer systems may …
Mathematical Modeling of Lake Tap Flows
- Engineering
- 2011
A lake tap is the submerged piercing of a tunnel at the intake to connect the reservoir to the tunnel system. It is referred to as a dry lake tap if the tunnel is dry before the blasting of the last…
Pipeline start-up with entrapped air
- Physics
- 1999
A mathematical model for the assessment of the pressure head maxima that air pockets within a pipeline can originate on start-up is presented. This model is based on a general model addressing the ...