{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T02:50:42Z","timestamp":1768272642380,"version":"3.49.0"},"reference-count":40,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2023,10,2]],"date-time":"2023-10-02T00:00:00Z","timestamp":1696204800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior\u2014Brasil (CAPES)","award":["001"],"award-info":[{"award-number":["001"]}]},{"name":"Pipeline Simulation Interest Group (PSIG)","award":["001"],"award-info":[{"award-number":["001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Water"],"abstract":"<jats:p>Air valves are protective devices often used in pressurised water pipelines, ideally admitting air to limit sub-atmospheric pressures and controlling the release of entrapped air. This work summarises a comprehensive sensitivity analysis of the transient behaviour in a rising water pipeline with an air valve following a pump trip. The paper examines the water hammer stages associated with a pump trip, namely, the initial depressurisation, followed by air admission, then air expulsion, and finally the creation of a secondary pressure wave. For each air valve location and specific set of design conditions, the relationship between the transient magnitude and air valve outflow capacity is found to be non-linear, but to roughly follow the shape of a logistic curve having a lower left plateau for attenuated (type 1) behaviour and transitioning through type 2 behaviour to a higher right plateau for water-hammer-dominated (type 3) behaviour. Through an extensive set of simulations covering a wide range of conditions, the study identifies the size of the critical outflow orifices associated with both type 1 and type 3 responses and assesses the influence of the location of the air valve on the transient magnitude and on the timing of air pocket collapse. Furthermore, the paper highlights that a non-slam air valve is capable of effectively mitigating transient magnitudes provided that its design parameters are judiciously chosen and account for both the system\u2019s attributes and the characteristics of the transient event.<\/jats:p>","DOI":"10.3390\/w15193476","type":"journal-article","created":{"date-parts":[[2023,10,2]],"date-time":"2023-10-02T11:56:49Z","timestamp":1696247809000},"page":"3476","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Exploring the Sensitivity of the Transient Response following Power Failure to Air Valve and Pipeline Characteristics"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6197-9329","authenticated-orcid":false,"given":"Elias","family":"Tasca","sequence":"first","affiliation":[{"name":"School of Civil Engineering, Architecture and Urban Design, State University of Campinas, Campinas 13083-889, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5222-0679","authenticated-orcid":false,"given":"Mohsen","family":"Besharat","sequence":"additional","affiliation":[{"name":"School of Civil Engineering, University of Leeds, Leeds LS2 9JT, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9028-9711","authenticated-orcid":false,"given":"Helena M.","family":"Ramos","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, Architecture and Georesources, CERIS, Instituto Superior T\u00e9cnico, University of Lisbon, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4606-4996","authenticated-orcid":false,"suffix":"Jr.","given":"Edevar","family":"Luvizotto","sequence":"additional","affiliation":[{"name":"School of Civil Engineering, Architecture and Urban Design, State University of Campinas, Campinas 13083-889, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9154-8722","authenticated-orcid":false,"given":"Bryan","family":"Karney","sequence":"additional","affiliation":[{"name":"Department of Civil and Mineral Engineering, University of Toronto, Toronto, ON M5S 1A4, Canada"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Tasca, E., Besharat, M., Ramos, H.M., Luvizotto, E., and Karney, B. (2023). Contribution of air management to the energy efficiency of water pipelines. Sustainability, 15.","DOI":"10.3390\/su15053875"},{"key":"ref_2","unstructured":"Martins, S.C. (2013). Din\u00e2mica da Pressuriza\u00e7\u00e3o de Sistemas Hidr\u00e1ulicos Com Ar Aprisionado. [Ph.D. Thesis, Instituto Superior T\u00e9cnico, Universidade T\u00e9cnica de Lisboa]."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"04020047","DOI":"10.1061\/(ASCE)HY.1943-7900.0001773","article-title":"Expulsion of entrapped air in a rapidly filling horizontal pipe","volume":"146","author":"Zhou","year":"2020","journal-title":"J. Hydraul. Eng."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1002\/j.1551-8833.2005.tb10892.x","article-title":"Hydraulic transient guidelines for protecting water distribution systems","volume":"97","author":"Boulos","year":"2005","journal-title":"J. Am. Water Work. Assoc."},{"key":"ref_5","unstructured":"American Water Works Association (AWWA) (2016). Manual of Water Supply Practices M51\u2013Air Valves: Air-Release, Air\/Vacuum and Combination, AWWA. [2nd ed.]."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Ramos, H.M., Fuertes-Miquel, V.S., Tasca, E., Coronado-Hern\u00e1ndez, O.E., Besharat, M., Zhou, L., and Karney, B. (2022). Concerning dynamic effects in pipe systems with two-phase flows: Pressure surges, cavitation, and ventilation. Water, 14.","DOI":"10.3390\/w14152376"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Garc\u00eda-Todol\u00ed, S., Iglesias-Rey, P.L., Mora-Meli\u00e1, D., Mart\u00ednez-Solano, F.J., and Fuertes-Miquel, V.S. (2018). Computational determination of air valves capacity using CFD techniques. Water, 10.","DOI":"10.3390\/w10101433"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Paternina-Verona, D.A., Coronado-Hern\u00e1ndez, O.E., Espinoza-Rom\u00e1n, H.G., Fuertes-Miquel, V.S., and Ramos, H.M. (2023). Rapid filling analysis with an entrapped air pocket in water pipelines using a 3D CFD model. Water, 15.","DOI":"10.3390\/w15050834"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"04023019","DOI":"10.1061\/JHEND8.HYENG-13420","article-title":"Improved air valve selection through better device characterization and modeling","volume":"149","author":"Tasca","year":"2023","journal-title":"J. Hydraul. Eng."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"04016083","DOI":"10.1061\/(ASCE)HY.1943-7900.0001235","article-title":"Water column separation and cavity collapse for pipelines protected with air vacuum valves: Understanding the essential wave processes","volume":"143","author":"Ramezani","year":"2017","journal-title":"J. Hydraul. Eng."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Tasca, E., Karney, B., Fuertes-Miquel, V.S., Dalfr\u00e9 Filho, J.G., and Luvizotto, E. (2022). The crucial importance of air valve characterization to the transient response of pipeline systems. Water, 14.","DOI":"10.3390\/w14172590"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"769","DOI":"10.1080\/1573062X.2018.1540711","article-title":"Backflow air and pressure analysis in emptying a pipeline containing an entrapped air pocket","volume":"15","author":"Besharat","year":"2018","journal-title":"Urban Water J."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"299","DOI":"10.1080\/1573062X.2019.1669188","article-title":"Hydraulic modeling during filling and emptying processes in pressurized pipelines: A literature review","volume":"16","year":"2019","journal-title":"Urban Water J."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"04021036","DOI":"10.1061\/(ASCE)HY.1943-7900.0001914","article-title":"Performance similarity between different-sized air exchange valves","volume":"147","author":"Tasca","year":"2021","journal-title":"J. Hydraul. Eng."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"04022022","DOI":"10.1061\/(ASCE)PS.1949-1204.0000660","article-title":"Influence of traditional and antislam air valve characteristics on transient pressure control","volume":"13","author":"Li","year":"2022","journal-title":"J. Pipeline Syst. Eng. Pract."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Apollonio, C., Balacco, G., Fontana, N., Giugni, M., Marini, G., and Piccinni, A.F. (2016). Hydraulic transients caused by air expulsion during rapid filling of undulating pipelines. Water, 8.","DOI":"10.3390\/w8010025"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"949","DOI":"10.1061\/(ASCE)HY.1943-7900.0000750","article-title":"Investigation of hydraulic transients of two entrapped air pockets in a water pipeline","volume":"139","author":"Zhou","year":"2013","journal-title":"J. Hydraul. Eng."},{"key":"ref_18","first-page":"949","article-title":"Study on the factors influencing air valve protection against water hammer with column separation and rejoinder","volume":"71","author":"Li","year":"2022","journal-title":"AQUA-Infrastruct. Ecosyst. Soc."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"20210339","DOI":"10.1098\/rspa.2021.0339","article-title":"Numerical validation of novel scaling laws for air entrainment in water","volume":"477","author":"Catucci","year":"2021","journal-title":"Proc. R. Soc. A"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"225","DOI":"10.5545\/sv-jme.2011.032","article-title":"Dynamic behaviour of air valves in a large-scale pipeline apparatus","volume":"58","author":"Bergant","year":"2012","journal-title":"Stroj. Vestn.-Mech. Eng."},{"key":"ref_21","first-page":"1444","article-title":"Three-dimensional CFD analysis of liquid slug acceleration and impact in a voided pipeline with end orifice","volume":"16","author":"He","year":"2022","journal-title":"Eng. Appl. Comput. Fluid Mech."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"120","DOI":"10.1080\/00221686.2022.2132309","article-title":"Energy dissipation in a rapid filling vertical pipe with trapped air","volume":"61","author":"Zhou","year":"2023","journal-title":"J. Hydraul. Res."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1189","DOI":"10.1139\/L10-066","article-title":"Effects of water\u2013air mixtures on hydraulic transients","volume":"37","author":"Pozos","year":"2010","journal-title":"Can. J. Civ. Eng."},{"key":"ref_24","unstructured":"Ramezani, L. (2015). An Exploration of Transient Protection of Pressurized Pipelines using Air Valves. [Ph.D. Thesis, University of Toronto]."},{"key":"ref_25","unstructured":"Coronado-Hern\u00e1ndez, O.E., Fuertes-Miquel, V.S., Besharat, M., and Ramos, H.M. (2018, January 14\u201316). A parametric sensitivity analysis of numerically modelled piston-type filling and emptying of an inclined pipeline with an air valve. Proceedings of the 13th International Conference on Pressure Surges, Bordeaux, France."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"04018045","DOI":"10.1061\/(ASCE)HY.1943-7900.0001491","article-title":"Dynamic behavior of entrapped air pocket in a water filling pipeline","volume":"144","author":"Zhou","year":"2018","journal-title":"J. Hydraul. Eng."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Chaudhry, M.H. (2014). Applied Hydraulic Transients, Springer. [3rd ed.].","DOI":"10.1007\/978-1-4614-8538-4"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Abdeldayem, O.M., Ferr\u00e0s, D., van der Zwan, S., and Kennedy, M. (2021). Analysis of unsteady friction models used in engineering software for water hammer analysis: Implementation case in WANDA. Water, 13.","DOI":"10.3390\/w13040495"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/j.jfluidstructs.2005.08.008","article-title":"Water hammer with column separation: A historical review","volume":"22","author":"Bergant","year":"2006","journal-title":"J. Fluids Struct."},{"key":"ref_30","unstructured":"Wylie, E.B., and Streeter, V.L. (1983). Fluid Transients, FEB Press."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1052","DOI":"10.1139\/cjce-2016-0209","article-title":"Numerical modelling of pipeline with air pockets and air valves","volume":"43","year":"2016","journal-title":"Can. J. Civ. Eng."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Zhang, X., Fan, C., Yu, X., Zhang, J., Lv, J., and Xu, T. (2019). Study on the mathematical model of vacuum breaker valve for large air mass conditions. Water, 11.","DOI":"10.3390\/w11071358"},{"key":"ref_33","unstructured":"Agostinho, M., Fernandes, C., and Jung, B. (2018, January 23\u201325). Assessment of hydraulic transient indicators in water supply network. Proceedings of the 1st International WDSA\/CCWI Joint Conference, Kingston, ON, Canada."},{"key":"ref_34","unstructured":"Jung, B., and Karney, B. (2011, January 23\u201324). Application of fluid transients on pipeline optimization: Worst-case scenario search and systematic protection. Proceedings of the Conference on Probabilistic Methodologies in Water and Wastewater Engineering, Toronto, ON, Canada."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"88","DOI":"10.1002\/j.1551-8833.2004.tb10652.x","article-title":"Pressure surges in pipeline systems resulting from air releases","volume":"96","author":"Lingireddy","year":"2004","journal-title":"J. Am. Water Work. Assoc."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Ostfeld, A. (2012). Water Supply System Analysis\u2013Selected Topics, InTech.","DOI":"10.5772\/2882"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"625","DOI":"10.1061\/(ASCE)0733-9429(2002)128:6(625)","article-title":"Transient flow in a rapidly filling horizontal pipe containing trapped air","volume":"128","author":"Zhou","year":"2002","journal-title":"J. Hydraul. Eng."},{"key":"ref_38","unstructured":"Lee, N.H. (2005). Effect of Pressurization and Expulsion of Entrapped Air in Pipelines. [Ph.D. Thesis, Georgia Institute of Technology]."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"307","DOI":"10.1080\/00221686.2018.1475427","article-title":"Rapid air expulsion through an orifice in a vertical water pipe","volume":"57","author":"Zhou","year":"2019","journal-title":"J. Hydraul. Res."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"04016082","DOI":"10.1061\/(ASCE)HY.1943-7900.0001245","article-title":"Pressure transients caused by air-valve closure while filling pipelines","volume":"143","author":"Tran","year":"2017","journal-title":"J. Hydraul. Eng."}],"container-title":["Water"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4441\/15\/19\/3476\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T21:04:09Z","timestamp":1760130249000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4441\/15\/19\/3476"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,10,2]]},"references-count":40,"journal-issue":{"issue":"19","published-online":{"date-parts":[[2023,10]]}},"alternative-id":["w15193476"],"URL":"https:\/\/doi.org\/10.3390\/w15193476","relation":{},"ISSN":["2073-4441"],"issn-type":[{"value":"2073-4441","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,10,2]]}}}