{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T23:49:38Z","timestamp":1778024978259,"version":"3.51.4"},"reference-count":32,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2024,6,2]],"date-time":"2024-06-02T00:00:00Z","timestamp":1717286400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Changzhou University Research Start-up Fund","award":["ZMF23020056"],"award-info":[{"award-number":["ZMF23020056"]}]},{"name":"Changzhou University Research Start-up Fund","award":["CQ20230103"],"award-info":[{"award-number":["CQ20230103"]}]},{"name":"Changzhou University Research Start-up Fund","award":["BK20210854"],"award-info":[{"award-number":["BK20210854"]}]},{"name":"Changzhou Leading Innovative Talent Project","award":["ZMF23020056"],"award-info":[{"award-number":["ZMF23020056"]}]},{"name":"Changzhou Leading Innovative Talent Project","award":["CQ20230103"],"award-info":[{"award-number":["CQ20230103"]}]},{"name":"Changzhou Leading Innovative Talent Project","award":["BK20210854"],"award-info":[{"award-number":["BK20210854"]}]},{"DOI":"10.13039\/501100004608","name":"Natural Science Foundation of Jiangsu Province","doi-asserted-by":"publisher","award":["ZMF23020056"],"award-info":[{"award-number":["ZMF23020056"]}],"id":[{"id":"10.13039\/501100004608","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004608","name":"Natural Science Foundation of Jiangsu Province","doi-asserted-by":"publisher","award":["CQ20230103"],"award-info":[{"award-number":["CQ20230103"]}],"id":[{"id":"10.13039\/501100004608","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004608","name":"Natural Science Foundation of Jiangsu Province","doi-asserted-by":"publisher","award":["BK20210854"],"award-info":[{"award-number":["BK20210854"]}],"id":[{"id":"10.13039\/501100004608","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Jiangsu Province Engineering Research Center of Intelligent Manufacturing Technology for the New Energy Vehicle Power Battery","award":["ZMF23020056"],"award-info":[{"award-number":["ZMF23020056"]}]},{"name":"Jiangsu Province Engineering Research Center of Intelligent Manufacturing Technology for the New Energy Vehicle Power Battery","award":["CQ20230103"],"award-info":[{"award-number":["CQ20230103"]}]},{"name":"Jiangsu Province Engineering Research Center of Intelligent Manufacturing Technology for the New Energy Vehicle Power Battery","award":["BK20210854"],"award-info":[{"award-number":["BK20210854"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Hypergolic ignition of H2O2 and MEA-NaBH4 by off-center collision of their droplets was experimentally studied, focusing on the characteristics and mechanism of droplet mixing, droplet heating and evaporation, and gas-phase ignition. The whole collision ignition process was divided into five stages, which were compared, respectively, with that of head-on collision. Under the condition of a slightly off-center collision (for cases where B &lt; 0.35), H2O2 droplets penetrate MEA-NaBH4 droplets after the collision and coalesce with it, but the internal H2O2 drop inside the MEA-NaBH4 droplet does not form a stable sphere. Instead, it rotates and expands inside the mixed droplet. With B increasing to 0.59, the droplets no longer coalesce after collision but separate away, forming satellite droplets. In such cases, multi-ignition mode is observed. When B increases to a certain extent, specifically, 0.85, a grazing collision is observed such that no mass transfer exists during the interaction of droplets, which leads to ignition failure. A theoretical model quantifying droplet swelling rate was established to calculate the volume change of the droplet. It was found that the swelling can be attributed to the flash boiling of superheated internal H2O2 fluid. Meanwhile, the ignition delay time was found to linearly decrease with B at various Wes until the extent where the chemical reaction takes over control, leading to an almost constant time delay defined as RDT. Additionally, the regime of ignition modes corresponding to different droplet mixing features is summarized in the We-B parametric space.<\/jats:p>","DOI":"10.3390\/sym16060682","type":"journal-article","created":{"date-parts":[[2024,6,3]],"date-time":"2024-06-03T10:06:01Z","timestamp":1717409161000},"page":"682","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Hypergolic Ignition by Off-Center Binary Collision of Monoethanolamine-NaBH4 and Hydrogen Peroxide Droplets"],"prefix":"10.3390","volume":"16","author":[{"given":"Dawei","family":"Zhang","sequence":"first","affiliation":[{"name":"School of Mechanical Engineering and Rail Transit, Changzhou University, Changzhou 213164, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Siduo","family":"Song","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering and Rail Transit, Changzhou University, Changzhou 213164, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dehai","family":"Yu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of High Temperature Gas Dynamics, Chinese Academy of Sciences, Beijing 100190, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yueming","family":"Yuan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of High Temperature Gas Dynamics, Chinese Academy of Sciences, Beijing 100190, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1426-8564","authenticated-orcid":false,"given":"Hongmei","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering and Rail Transit, Changzhou University, Changzhou 213164, China"},{"name":"Jiangsu Province Engineering Research Center of Intelligent Manufacturing Technology for the New Energy Vehicle Power Battery, Changzhou 213164, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-4582-1839","authenticated-orcid":false,"given":"Xuedong","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering and Rail Transit, Changzhou University, Changzhou 213164, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xuejun","family":"Fan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of High Temperature Gas Dynamics, Chinese Academy of Sciences, Beijing 100190, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,2]]},"reference":[{"key":"ref_1","unstructured":"Fletcher, E.A., and Morrell, G. 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