{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T11:58:31Z","timestamp":1777895911168,"version":"3.51.4"},"reference-count":31,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,4,20]],"date-time":"2025-04-20T00:00:00Z","timestamp":1745107200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"YURA Co., Ltd. (Republic of Korea)","award":["2020R1A2C1011555"],"award-info":[{"award-number":["2020R1A2C1011555"]}]},{"name":"YURA Co., Ltd. (Republic of Korea)","award":["20024894"],"award-info":[{"award-number":["20024894"]}]},{"name":"Korea government (MSIT)","award":["2020R1A2C1011555"],"award-info":[{"award-number":["2020R1A2C1011555"]}]},{"name":"Korea government (MSIT)","award":["20024894"],"award-info":[{"award-number":["20024894"]}]},{"name":"Korean government (MOTIE)","award":["2020R1A2C1011555"],"award-info":[{"award-number":["2020R1A2C1011555"]}]},{"name":"Korean government (MOTIE)","award":["20024894"],"award-info":[{"award-number":["20024894"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>The increasing demand for ultra-fast charging in electric vehicles (EVs) necessitates advancements in thermal management strategies to mitigate Joule heating, which arises due to electrical resistance in charging connectors and cable cores. This study presents a numerical analysis of immersion cooling performance for ultra-fast chargers under realistic charging conditions. The simulated results are validated by experiments with a maximum deviation of 5.5% at 600 A and 700 A currents. The novelty of this work lies in the consideration of a realistic charging cable length of 5 m, the evaluation of temperature characteristics in the charger connector, and the analysis of geometric symmetry in the charging cable and coolant configuration to ensure uniform heat distribution. Key operating conditions were systematically analyzed, including applied currents, ambient temperatures, coolant flow rates, cable core cross-sectional areas, and different types of coolants. Results indicate that increasing the applied current from 400 A to 800 A raised the connector temperature from 60.73 \u00b0C to 97.33 \u00b0C. As the ambient temperature increased from 20 \u00b0C to 50 \u00b0C, the connector temperature rose significantly from 42.71 \u00b0C to 74.99 \u00b0C, while the maximum cable core temperature increased from 65.26 \u00b0C to 100.61 \u00b0C. Increasing the cable core cross-sectional area from 20 mm2 to 30 mm2 reduced the connector temperature from 77.20 \u00b0C to 74.99 \u00b0C. Meanwhile, increasing the coolant flow rate from 2 LPM to 5 LPM had a negligible effect on the connector temperature. Among the three tested coolants, Novec 7500 exhibited the highest cooling efficiency, achieving the lowest contact temperature (74.76 \u00b0C) and the highest performance evaluation criteria (PEC) value of 3.8. This study provides valuable guidelines for enhancing symmetry-driven thermal management systems and demonstrates the potential of immersion cooling to improve efficiency, safety, and operational reliability in next-generation high-power EV chargers.<\/jats:p>","DOI":"10.3390\/sym17040624","type":"journal-article","created":{"date-parts":[[2025,4,20]],"date-time":"2025-04-20T20:31:36Z","timestamp":1745181096000},"page":"624","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Numerical Analysis on Cooling Performances for Connectors Using Immersion Cooling in Ultra-Fast Chargers for Electric Vehicles"],"prefix":"10.3390","volume":"17","author":[{"given":"Seong-Guk","family":"Hwang","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Dong-A University, 37 Nakdong-Daero 550, Saha-gu, Busan 49315, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8857-4444","authenticated-orcid":false,"given":"Moo-Yeon","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Dong-A University, 37 Nakdong-Daero 550, Saha-gu, Busan 49315, Republic of Korea"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-7527-8784","authenticated-orcid":false,"given":"Beom-Seok","family":"Ko","sequence":"additional","affiliation":[{"name":"Yura Co., Ltd., 308, Pangyo-ro, Bundang-gu, Seongnam-si 13494, Republic of Korea"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"103321","DOI":"10.1016\/j.tsep.2025.103321","article-title":"Can the world harmonized steady cycle (WHSC) accurately reflect real-world driving conditions for heavy-duty diesel engine emission valuations? 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