Study of Performance and Combustion in Ammonia-Fueled CI Engines via Diesel Simultaneous Injection

Study of Performance and Combustion in Ammonia-Fueled CI Engines via Diesel Simultaneous Injection | 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 Study of Performance and Combustion in Ammonia-Fueled CI Engines via Diesel Simultaneous Injection Anadi Kapoor, Dr. Jayashish Kumar Pandey, George Varghese This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9091700/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 18 You are reading this latest preprint version Abstract Ammonia is a promising carbon-free hydrogen-carrier with wide industrial availability, yet its low flame speed, high latent heat, and narrow flammability pose challenges for compression ignition engines. This study investigates ammonia–diesel dual-fuel operation at 50% and 80% loads, with diesel injection pressures varied from 200 to 340 bar, and ammonia energy shares (AES) ranging from 0% to 40% to observe the sustainability of ammonia fuel in light-duty engines. Experimental results show that increasing injection pressure enhanced cylinder pressure by up to 10% at low AES and advanced peak pressure timing, partially compensating for ammonia’s slow combustion. The heat release rate (HRR), delayed by 5–9°CA with increasing AES, was improved at higher injection pressures, with HRR peaks shifting to the controlled combustion phase. Ignition delay increased with AES, reaching 4.5°CA at 40% ammonia at 200 bar compared to diesel at 320 bar, but was reduced to 2.78°CA at an injection pressure of 320 bar. Cycle-to-cycle variations, quantified by CoV imep , rose with AES due to prolonged combustion but decreased by up to 27% with optimized injection pressure. However, at 40% AES, stability improvement plateaued at 300 bar. Brake-specific fuel consumption (BSFC) increased by up to 48% at high AES, while higher load and injection pressure partially mitigated the rise. Despite increased fuel consumption, operating costs remained relatively low, increasing by ₹3.3/kWh at 50% load and ₹1.3/kWh at 80% load for 40% AES. The results indicate that electronically controlled high-pressure ammonia injection combined with higher compression ratios can enhance combustion quality, improve thermal efficiency, and reduce the effective fuel cost in ammonia–diesel dual-fuel engines. Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 07 May, 2026 Reviews received at journal 28 Apr, 2026 Reviews received at journal 20 Apr, 2026 Reviews received at journal 19 Apr, 2026 Reviewers agreed at journal 15 Apr, 2026 Reviewers agreed at journal 13 Apr, 2026 Reviews received at journal 13 Apr, 2026 Reviewers agreed at journal 13 Apr, 2026 Reviews received at journal 12 Apr, 2026 Reviewers agreed at journal 12 Apr, 2026 Reviewers agreed at journal 12 Apr, 2026 Reviewers agreed at journal 11 Apr, 2026 Reviews received at journal 10 Apr, 2026 Reviewers agreed at journal 09 Apr, 2026 Reviewers invited by journal 27 Mar, 2026 Editor assigned by journal 12 Mar, 2026 Submission checks completed at journal 12 Mar, 2026 First submitted to journal 11 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. 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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-9091700","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":613423321,"identity":"31d4ef27-8224-4f7f-9d8e-a127f0879163","order_by":0,"name":"Anadi Kapoor","email":"","orcid":"","institution":"Manipal Academy of Higher Education","correspondingAuthor":false,"prefix":"","firstName":"Anadi","middleName":"","lastName":"Kapoor","suffix":""},{"id":613423322,"identity":"acaf05ef-e1c7-488e-af72-4a09ed75f03f","order_by":1,"name":"Dr. Jayashish Kumar Pandey","email":"data:image/png;base64,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","orcid":"","institution":"Manipal Academy of Higher Education","correspondingAuthor":true,"prefix":"Dr.","firstName":"Jayashish","middleName":"Kumar","lastName":"Pandey","suffix":""},{"id":613423323,"identity":"767b4ca0-b0c9-45ef-9e79-7d73b73ab06e","order_by":2,"name":"George Varghese","email":"","orcid":"","institution":"Manipal Academy of Higher Education","correspondingAuthor":false,"prefix":"","firstName":"George","middleName":"","lastName":"Varghese","suffix":""}],"badges":[],"createdAt":"2026-03-11 08:08:31","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9091700/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9091700/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105904835,"identity":"cc5ca92e-5345-4448-8b8a-009c08472f09","added_by":"auto","created_at":"2026-04-01 10:10:43","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3419564,"visible":true,"origin":"","legend":"","description":"","filename":"1.ManuscriptDNH.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9091700/v1_covered_afccd054-13c9-4789-9a23-b52ef09dce64.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eStudy of Performance and Combustion in Ammonia-Fueled CI Engines via Diesel Simultaneous Injection\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":"discover-applied-sciences","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Applied Sciences](https://link.springer.com/journal/42452)","snPcode":"42452","submissionUrl":"https://submission.springernature.com/new-submission/42452/3","title":"Discover Applied Sciences","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-9091700/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9091700/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eAmmonia is a promising carbon-free hydrogen-carrier with wide industrial availability, yet its low flame speed, high latent heat, and narrow flammability pose challenges for compression ignition engines. This study investigates ammonia\u0026ndash;diesel dual-fuel operation at 50% and 80% loads, with diesel injection pressures varied from 200 to 340 bar, and ammonia energy shares (AES) ranging from 0% to 40% to observe the sustainability of ammonia fuel in light-duty engines. Experimental results show that increasing injection pressure enhanced cylinder pressure by up to 10% at low AES and advanced peak pressure timing, partially compensating for ammonia\u0026rsquo;s slow combustion. The heat release rate (HRR), delayed by 5\u0026ndash;9\u0026deg;CA with increasing AES, was improved at higher injection pressures, with HRR peaks shifting to the controlled combustion phase. Ignition delay increased with AES, reaching 4.5\u0026deg;CA at 40% ammonia at 200 bar compared to diesel at 320 bar, but was reduced to 2.78\u0026deg;CA at an injection pressure of 320 bar. Cycle-to-cycle variations, quantified by CoV\u003csub\u003eimep\u003c/sub\u003e, rose with AES due to prolonged combustion but decreased by up to 27% with optimized injection pressure. However, at 40% AES, stability improvement plateaued at 300 bar. Brake-specific fuel consumption (BSFC) increased by up to 48% at high AES, while higher load and injection pressure partially mitigated the rise. Despite increased fuel consumption, operating costs remained relatively low, increasing by ₹3.3/kWh at 50% load and ₹1.3/kWh at 80% load for 40% AES. The results indicate that electronically controlled high-pressure ammonia injection combined with higher compression ratios can enhance combustion quality, improve thermal efficiency, and reduce the effective fuel cost in ammonia\u0026ndash;diesel dual-fuel engines.\u003c/p\u003e","manuscriptTitle":"Study of Performance and Combustion in Ammonia-Fueled CI Engines via Diesel Simultaneous Injection","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-31 17:43:39","doi":"10.21203/rs.3.rs-9091700/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-05-07T12:30:09+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-28T09:10:18+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-20T14:38:18+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-19T12:25:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"101185119482237749642470140657289711246","date":"2026-04-15T07:10:01+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"133296255008218319373402860053579818251","date":"2026-04-14T03:24:00+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-13T07:26:18+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"106677999578512084352612220909509051130","date":"2026-04-13T06:54:35+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-12T22:36:31+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"232090233938382684400776885648061408002","date":"2026-04-12T11:13:40+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"168979760517054962862158712369604331046","date":"2026-04-12T10:47:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"173951610032133481700207718073669067555","date":"2026-04-11T11:33:50+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-10T08:08:47+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"338791323638407846325478656890721047185","date":"2026-04-09T12:38:58+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-27T15:38:46+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-12T14:22:20+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-12T14:21:50+00:00","index":"","fulltext":""},{"type":"submitted","content":"Discover Applied Sciences","date":"2026-03-11T07:55:04+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"discover-applied-sciences","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Applied Sciences](https://link.springer.com/journal/42452)","snPcode":"42452","submissionUrl":"https://submission.springernature.com/new-submission/42452/3","title":"Discover Applied Sciences","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"0c17a3e1-517c-4736-8b09-7de1515d1bd6","owner":[],"postedDate":"March 31st, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Revision requested","date":"2026-05-07T12:30:09+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-14T22:23:04+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-31 17:43:39","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9091700","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9091700","identity":"rs-9091700","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}