Numerical Investigation for the Cooling Performance of Circular and Rectangular Ground-Coupled Heat Exchangers with Different Geometrical Layouts

Numerical Investigation for the Cooling Performance of Circular and Rectangular Ground-Coupled Heat Exchangers with Different Geometrical Layouts | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Numerical Investigation for the Cooling Performance of Circular and Rectangular Ground-Coupled Heat Exchangers with Different Geometrical Layouts Sudhir Kumar, Narendra Gajbhiye This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9106831/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract Ground-coupled heat exchangers use geothermal energy storage to provide a sustainable solution for heating, ventilation, and air conditioning. In this study, the performance of circular- and rectangular-cross-section ground-coupled heat exchangers with four layouts (simple horizontal, U-shaped, helical, and slinky) is numerically simulated. It has been found that the rectangular GCHE maintains a more stable air temperature and achieves the maximum temperature drop at a shorter length across all layouts. The temperature at the exit of a circular GCHE with horizontal, U-shaped, helical, and slinky layouts is found to be 302.159 K, 301.586 K, 300.647 K, and 300.20 K, respectively, while the same temperatures are achieved in rectangular GCHEs with corresponding layouts at sections of 18.82 m, 17.46 m, 16.09 m, and 15.43 m, respectively. The length of the slinky layout with a circular cross-section GCHE is reduced by 17%, 13%, and 6% relative to the horizontal, U-shaped, and helical layouts, respectively. In comparison, reductions of 23%, 19%, and 8% are observed for the rectangular cross-section in the corresponding layouts. The inlet velocity significantly impacts the thermal performance of the GCHE, with the maximum temperature reduction occurring at a flow rate of 1 m/s. The average cooling capacity of rectangular cross-sectional GCHE is more than 40% higher than that of circular GCHE for all the layouts studied. The maximum cooling capacity is observed at a higher inlet air temperature of 323 K for a rectangular GCHE with a slinky layout. The friction factor and pressure drop are found to increase with the increase in the Reynolds number. The rectangular GCHEs provides 19.8% – 40.34% higher cooling capacity compared to circular GCHEs at air velocity increases from 1 m/s to 5 m/s. GCHE Thermal performance Friction factor Air temperature Reynolds number Effectiveness Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 18 May, 2026 Reviews received at journal 08 Apr, 2026 Reviewers agreed at journal 05 Apr, 2026 Reviewers invited by journal 05 Apr, 2026 Editor assigned by journal 14 Mar, 2026 Submission checks completed at journal 14 Mar, 2026 First submitted to journal 12 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9106831","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":619523845,"identity":"d86944c6-9d0e-4293-9be6-c95caeb269e0","order_by":0,"name":"Sudhir Kumar","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA0ElEQVRIiWNgGAWjYLAC3gYJBgn2BiDLwIIULTwHQFokiNbCwCAhkQBiEqHFXPr4M4m3OyzyJWc+v7rhR4EEA397dwJeLZZ9OWaSc89IWM6Wzim72QN0mMSZsxvwajE4w8MmzdsmYSAnnZN2gweoxUAil5AW9mcQLZJn0m7+IU4LgxlYi7QE+7HbRNli2cNjbDkXqEWyJ4fttoyBBA9Bv5jzsD+88batzkDi+PFnN9/8sZHjb+8l4DAEkwfM5sGrHE0L+wOCqkfBKBgFo2BkAgBXrj/Vtxp6ngAAAABJRU5ErkJggg==","orcid":"","institution":"Maulana Azad National Institute of Technology","correspondingAuthor":true,"prefix":"","firstName":"Sudhir","middleName":"","lastName":"Kumar","suffix":""},{"id":619523846,"identity":"50dba366-c3fb-4596-bd25-6452afacb233","order_by":1,"name":"Narendra Gajbhiye","email":"","orcid":"","institution":"Maulana Azad National Institute of Technology","correspondingAuthor":false,"prefix":"","firstName":"Narendra","middleName":"","lastName":"Gajbhiye","suffix":""}],"badges":[],"createdAt":"2026-03-12 16:09:09","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9106831/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9106831/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":106959646,"identity":"28770636-bd24-4dbc-afd9-6cca7fd4a470","added_by":"auto","created_at":"2026-04-15 09:12:49","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":898447,"visible":true,"origin":"","legend":"","description":"","filename":"FinalPapermarch2026.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9106831/v1_covered_2cbd92af-b412-4422-bd10-76783a2913ca.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eNumerical Investigation for the Cooling Performance of Circular and Rectangular Ground-Coupled Heat Exchangers with Different Geometrical Layouts\u003c/strong\u003e\u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"iranian-journal-of-science-and-technology-transactions-of-mechanical-engineering","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"istm","sideBox":"Learn more about [Iranian Journal of Science and Technology, Transactions of Mechanical Engineering](https://link.springer.com/journal/40997)","snPcode":"40997","submissionUrl":"https://submission.springernature.com/new-submission/40997/3","title":"Iranian Journal of Science and Technology, Transactions of Mechanical Engineering","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"GCHE, Thermal performance, Friction factor, Air temperature, Reynolds number, Effectiveness","lastPublishedDoi":"10.21203/rs.3.rs-9106831/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9106831/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eGround-coupled heat exchangers use geothermal energy storage to provide a sustainable solution for heating, ventilation, and air conditioning. 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