{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,10]],"date-time":"2026-01-10T08:25:12Z","timestamp":1768033512299,"version":"3.49.0"},"reference-count":21,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,5,6]],"date-time":"2023-05-06T00:00:00Z","timestamp":1683331200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Portuguese Foundation for Science and Technology (FCT)","award":["823802"],"award-info":[{"award-number":["823802"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Energies"],"abstract":"<jats:p>This work demonstrates that the quasi-homogeneous distribution of concentrated solar flux is achievable by using double paraboloid reflection, with a primary reflector to concentrate the sunlight, and a secondary reflector to homogenise the radiation flux. For that, three slightly different secondary reflectors were designed and manufactured, matching the specifications of the paraboloid concentrator of the SF60 solar furnace located in PSA\u2014Plataforma Solar de Almer\u00eda, which was used as primary reflector. Starting from preliminary simulations of the optical apparatus, the secondary geometries were selected and then the reflectors were manufactured from 7075-T6 aluminium alloy, using conventional and CNC machining technologies, with further processing to achieve a mirror-like finish. The results obtained from solar irradiation tests corroborate that the \u201cdouble paraboloid reflection\u201d methodology proposed in previous theoretical works seems to be technically feasible and can be a solution for obtaining homogeneously distributed fluxes of highly concentrated solar radiation.<\/jats:p>","DOI":"10.3390\/en16093927","type":"journal-article","created":{"date-parts":[[2023,5,8]],"date-time":"2023-05-08T02:29:22Z","timestamp":1683512962000},"page":"3927","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Experimental Validation of Double Paraboloid Reflection for Obtaining Quasi-Homogeneous Distribution of Concentrated Solar Flux"],"prefix":"10.3390","volume":"16","author":[{"given":"Gon\u00e7alo","family":"Domingos","sequence":"first","affiliation":[{"name":"IDMEC\u2014Instituto de Engenharia Mec\u00e2nica, Instituto Superior T\u00e9cnico, University of Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1608-4387","authenticated-orcid":false,"given":"Jos\u00e9 Carlos Garcia","family":"Pereira","sequence":"additional","affiliation":[{"name":"Departamento de Engenharia Qu\u00edmica, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3363-0151","authenticated-orcid":false,"given":"Pedro Alexandre Rodrigues","family":"Rosa","sequence":"additional","affiliation":[{"name":"IDMEC\u2014Instituto de Engenharia Mec\u00e2nica, Instituto Superior T\u00e9cnico, University of Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"}]},{"given":"Jos\u00e9","family":"Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"CIEMAT\u2014Centro de Investigaciones Energ\u00e9ticas, Medioambientales y Tecnol\u00f3gicas, PSA\u2014Plataforma Solar de Almer\u00eda, Apartado 22, 04200 Tabernas, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4730-3765","authenticated-orcid":false,"given":"Lu\u00eds Guerra","family":"Rosa","sequence":"additional","affiliation":[{"name":"IDMEC\u2014Instituto de Engenharia Mec\u00e2nica, Instituto Superior T\u00e9cnico, University of Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1002\/wene.79","article-title":"Solar thermal CSP technology","volume":"3","author":"Romero","year":"2014","journal-title":"WIREs Energy Environ."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1016\/j.solener.2017.07.046","article-title":"High-flux optical systems for solar thermochemistry","volume":"156","author":"Bader","year":"2017","journal-title":"Sol. Energy"},{"key":"ref_3","unstructured":"Lipinski, W. (2021). Solar Thermochemistry, Elsevier Inc.. [1st ed.]."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Pereira, J.C.G., Fernandes, J.C., and Rosa, L.G. (2019). Mathematical models for simulation and optimization of high-flux solar furnaces. Math. Comput. 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