{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:53:45Z","timestamp":1760147625937,"version":"build-2065373602"},"reference-count":50,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,2,21]],"date-time":"2023-02-21T00:00:00Z","timestamp":1676937600000},"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","award":["001"],"award-info":[{"award-number":["001"]}]},{"name":"Pipeline Simulation Interest Group","award":["001"],"award-info":[{"award-number":["001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sustainability"],"abstract":"<jats:p>Water conveyance systems are notorious for incurring considerable energy expenditures, either as losses of gravitational potential energy or as increased electricity consumption. Entrapped air pockets, originating from ineffective or nonexistent air management schemes, are common and often significant contributors to these energy costs. This work summarizes the detrimental influence of entrapped air on the energetics and conveyance capacity of pressurized pipelines and identifies those conditions that typically result in temporary or persistent air accumulations. Gravity and pumped lines are considered and gravity lines are shown to be more prone to the negative effects of entrapped air. In addition, initially robust air management strategies can gradually degrade if poorly adjusted to evolving circumstances. The paper critically assesses two common air management strategies: through employing air valves or by air removal by hydraulic means\u2014that is, by considering a line\u2019s configuration along with an attempt to predict the necessary flow conditions for the hydraulic removal of entrapped air.<\/jats:p>","DOI":"10.3390\/su15053875","type":"journal-article","created":{"date-parts":[[2023,2,21]],"date-time":"2023-02-21T02:07:44Z","timestamp":1676945264000},"page":"3875","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Contribution of Air Management to the Energy Efficiency of Water Pipelines"],"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":[[2023,2,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"284","DOI":"10.1126\/science.289.5477.284","article-title":"Global water resources: Vulnerability from climate change and population growth","volume":"289","author":"Green","year":"2000","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"04021044","DOI":"10.1061\/(ASCE)WR.1943-5452.0001376","article-title":"Water\u2013energy nexus\u2013based economic optimization of water supply projects","volume":"147","author":"Hamzekhani","year":"2021","journal-title":"J. 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