{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T05:10:47Z","timestamp":1773465047635,"version":"3.50.1"},"posted":{"date-parts":[[2026]]},"group-title":"SSRN","reference-count":41,"publisher":"Elsevier BV","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>Heat pumps are widely favored for their energy efficiency, versatility, and ability to provide both seasonal cooling and heating. However, their performance and environmental impact are largely affected by the refrigerant type and heat exchanger design. In the present study, compact and highly efficient oval-tube heat exchangers (OTHE) are proposed. The proposed OTHE offers volume and mass reduction for the condenser, while providing superior heat transfer characteristics, compared to the conventional fin-tube heat exchangers (FTHE) in heat pumps. An experimental investigation was conducted to evaluate system performance using R410A, R290, and R32 across different refrigerant charges and various capillary lengths using OTHE in a heat pump. Experimental results show that the required refrigerant charge for R410A and R32 was reduced by 13.7 and 44.2%, respectively, while the cooling capacity increased by 4.3 and 4.8%. Notably, utilizing OTHE with R32 had the highest coefficient of performance (COP), outperforming other refrigerants by 8.3%. Furthermore, the consumed power decreased by 2.4%, 7.4%, and 12.9% for R410A, R290, and R32, respectively. Overall, the COP increased by 1.3% for the system using R410A and R32.<\/jats:p>","DOI":"10.2139\/ssrn.6412540","type":"posted-content","created":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T04:40:07Z","timestamp":1773463207000},"source":"Crossref","is-referenced-by-count":0,"title":["Experimental investigation of the heat pump performance based on an oval-tube heat exchanger"],"prefix":"10.2139","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-4760-6091","authenticated-orcid":true,"given":"A.","family":"Haggag","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3799-9738","authenticated-orcid":true,"given":"Mahmoud","family":"Said","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"W.G.","family":"Alshaer","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6117-3456","authenticated-orcid":true,"given":"Shinsuke","family":"Mori","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ahmed","family":"Hawwash","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"78","reference":[{"key":"ref1","article-title":"Engineering Science Reference, an imprint of IGI Global","volume":"2","author":"Pedro. 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