Investigation of Hydraulic Transients of Two Entrapped Air Pockets in a Water Pipeline
Publication: Journal of Hydraulic Engineering
Volume 139, Issue 9
Abstract
Transient pressure associated with a rapidly filling pipeline containing two entrapped air pockets is investigated experimentally and numerically. A multiple-air-pocket elastic-water model considering multiple moving boundaries of water columns is developed by neglecting inertia and head loss of a short water column near air–water interfaces. The proposed model is validated by experimental data. Results show that when two air pockets in length are much different, the maximum pressure always arises in the smaller air pocket regardless of the blocking column’s length. The case of the upstream air pocket with a similar length to the downstream is the most complicated and dangerous because (1) the maximum pressure may alternately arise in two air pockets as the blocking column increases, and (2) interaction of two air pockets could cause a huge pressure surge, which is likely much higher than with only one air pocket. The existing single-air-pocket model cannot effectively simulate pressure surge of the two air pockets.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China (Grant No. 50979029 and No. 51209073), Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20120094120002), and the China Scholar Council (CSC), File No. 2009671024.
References
Abreu, J., Cabrera, E., García-Serra, J., Iglesias, P., and Izquierdo, J. (1992). “Influence of trapped air pockets in pumping systems.” 4th Int. Conf. Hydraul. Eng. Software Hydrosoft, Computational Mechanics Publications, Boston, MA.
Cabrera, E., Abreu, J., Perez, R., and Vela, A. (1992). “Influence of liquid length variation in hydraulic transients.” J. Hydraul. Eng., 118(12), 1639–1650.
Chaudhry, M. H., and Reddy, H. P. (2011). “Mathematical modeling of lake tap flows.” J. Hydraul. Eng., 137(5), 611–614.
De Martino, G., Fontana, N., and Giugni, M. (2008). “Transient flow caused by air expulsion through an orifice.” J. Hydraul. Eng., 134(9), 1395–1399.
Fuertes, V. S., Arregui, F., Cabrera, E., and Iglesias, P. L. (2000). “Experimental setup of entrapped air pockets model validation.” 8th Int. Conf. Pressure Surges-Safe Design and Operation of Industrial Pipe Systems, Professional Engineering Publishing Limited, London, UK, 133–145.
Fuertes, V. S., Cabrera, E., Izquierdo, J., and Iglesias, P. L. (1999). “Peak pressure evaluation in pipelines with entrapped air pockets.” Proc., 3rd ASME/JSME Joint Fluids Eng. Conf., American Society of Mechanical Engineers, New York.
Graze, H. R. (1996). “Thermodynamic behavior of entrapped air in an air chamber.” 7th Int. Conf. Pressure Surges, BHR Group, Bedfordshire, UK, 549–560.
Izquierdo, J., Fuertes, V. S., Cabrera, E., Iglesias, P. L., and Garcia-Serra, J. (1999). “Pipeline start-up with entrapped air.” J. Hydraul. Res., 37(5), 579–590.
Lee, N. H., and Martin, C. S. (1999). “Experimental and analytical investigation of entrapped air in a horizontal pipe.” Proc., 3rd ASME/JSME Joint Fluids Eng. Conf., American Society of Mechanical Engineers (ASME), New York, 1–8.
Liu, D. Y., Zhou, L., Karney, B., Zhang, Q. F., and Ou, C. Q. (2011). “Rigid-plug elastic-water model for transient pipe flow with entrapped air pocket.” J. Hydraul. Res., 49(6), 799–803.
Martin, C. S. (1976). “Entrapped air in pipelines.” Proc., 2nd Int. Conf. Pressure Surges, British Hydromechanics Research Association (BHRA) Fluid Engineering, Cranfield, Bedford, England, 15–27.
Ruus, E., and Karney, B. W. (1997). Applied hydraulic transients, Ruus Consulting, Kelowna, BC, Canada.
Thorley, A. R. D. (2004). Fluid transients in pipeline systems, Professional Engineering Publishing, London.
Wylie, E. B., and Streeter, V. L. (1993). Fluid transients in systems, Prentice Hall, New York.
Zhou, F., Hicks, F. E., and Steffler, P. M. (2002). “Transient flow in a rapidly filling horizontal pipe containing trapped air.” J. Hydraul. Eng., 128(6), 625–634.
Zhou, L., Liu, D., Karney, B., and Zhang, Q. (2011a). “Influence of entrapped air pockets on hydraulic transients in water pipelines.” J. Hydraul. Eng., 137(12), 1686–1692.
Zhou, L., Liu, D., Karney, B., and Zhang, Q. (2013). “Closure to ‘influence of entrapped air pockets on hydraulic transients in water pipelines’.” J. Hydraul. Eng., 139(1), 107–108.
Zhou, L., Liu, D. Y., and Ou, C. Q. (2011b). “Simulation of flow transients in a water filling pipe containing entrapped air pocket with VOF model.” Eng. Appl. Comput. Fluid Mech., 5(1), 127–140.
Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 139 • Issue 9 • September 2013
Pages: 949 - 959
Copyright
© 2013 American Society of Civil Engineers.
History
Received: May 10, 2012
Accepted: Feb 21, 2013
Published online: Feb 23, 2013
Discussion open until: Jul 23, 2013
Published in print: Sep 1, 2013
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.