{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T20:40:56Z","timestamp":1775076056077,"version":"3.50.1"},"reference-count":62,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,7,31]],"date-time":"2022-07-31T00:00:00Z","timestamp":1659225600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","award":["SFRH\/BD\/39502\/2007"],"award-info":[{"award-number":["SFRH\/BD\/39502\/2007"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","award":["001"],"award-info":[{"award-number":["001"]}]},{"name":"Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior\u2014Brasil (CAPES)","award":["SFRH\/BD\/39502\/2007"],"award-info":[{"award-number":["SFRH\/BD\/39502\/2007"]}]},{"name":"Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior\u2014Brasil (CAPES)","award":["001"],"award-info":[{"award-number":["001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Water"],"abstract":"<jats:p>The risks associated with unsteady two-phase flows in pressurized pipe systems must be considered both in system design and operation. To this end, this paper summarizes experimental tests and numerical analyses that highlight key aspects of unsteady two-phase flows in water pipelines. The essential dynamics of air\u2013water interactions in unvented lines are first considered, followed by a summary of how system dynamics change when air venting is provided. System behaviour during unsteady two-phase flows is shown to be counter-intuitive, surprising, and complex. The role of air valves as protection devices is considered as is the reasonableness of the usual assumptions regarding air valve behaviour. The paper then numerically clarifies the relevance of cavitation and air valve performance to both the predicted air exchanges through any installed air valves and their role in modifying system behaviour during unsteady flows.<\/jats:p>","DOI":"10.3390\/w14152376","type":"journal-article","created":{"date-parts":[[2022,8,1]],"date-time":"2022-08-01T23:49:27Z","timestamp":1659397767000},"page":"2376","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Concerning Dynamic Effects in Pipe Systems with Two-Phase Flows: Pressure Surges, Cavitation, and Ventilation"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9028-9711","authenticated-orcid":false,"given":"Helena M.","family":"Ramos","sequence":"first","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\/0000-0003-3524-2555","authenticated-orcid":false,"given":"Vicente S.","family":"Fuertes-Miquel","sequence":"additional","affiliation":[{"name":"Department of Hydraulic and Environmental Engineering, Universitat Polit\u00e8cnica de Val\u00e8ncia, 46022 Valencia, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6197-9329","authenticated-orcid":false,"given":"Elias","family":"Tasca","sequence":"additional","affiliation":[{"name":"School of Civil Engineering, Architecture and Urban Design, State University of Campinas, Campinas 13083-889, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6574-0857","authenticated-orcid":false,"given":"Oscar E.","family":"Coronado-Hern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda, Universidad Tecnol\u00f3gica de Bol\u00edvar, Cartagena 131001, Colombia"}]},{"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\/0000-0002-1750-6126","authenticated-orcid":false,"given":"Ling","family":"Zhou","sequence":"additional","affiliation":[{"name":"College of Water Conservancy and Hydropower Engineering, Hohai University, 1 Xikang Rd., Nanjing 210098, China"}]},{"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":[[2022,7,31]]},"reference":[{"key":"ref_1","unstructured":"Lauchlan, C.S., Escarameia, M., May, R.W.P., Burrows, R., and Gahan, C. 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