{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T17:46:56Z","timestamp":1776966416191,"version":"3.51.4"},"reference-count":33,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T00:00:00Z","timestamp":1776902400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>The foaming of hydrogels presents a promising strategy for tailoring mechanical and radiological properties to replicate biological soft tissues for biomedical phantom applications. A computational fluid dynamics (CFD) framework is developed to predict void fraction distribution in alginate hydrogel precursor solutions aerated by air injection through a bottom nozzle. The objective is to use the framework for the design of the foaming system to match the desired gas-fraction distribution and radiological property. Seven parametric cases are investigated, varying inlet air velocity, alginate concentration, and surface tension. Results show that higher inlet velocities promote stronger jet penetration and greater gas accumulation, while increasing alginate concentration confines the bubble plume, with quasi-steady gas fractions displaying a non-monotonic trend with concentration. Elevated surface tension yields broader plume coverage and improved gas distribution uniformity at the expense of peak void fraction. The predicted void fractions map to Hounsfield Unit (HU) values of \u221234 to \u2212103, corresponding to adipose and fatty breast tissue attenuation (\u221250 to \u2212150 HU). The peak gas fraction at 5.0 wt% alginate yields \u2212307 HU, approaching published experimental CT measurements for the same formulation (\u2212460 to \u2212233 HU).<\/jats:p>","DOI":"10.3390\/gels12050355","type":"journal-article","created":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T17:04:59Z","timestamp":1776963899000},"page":"355","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Processing and Modeling of Alginate Hydrogel for Radiologically-Equivalent Biomedical Phantoms"],"prefix":"10.3390","volume":"12","author":[{"given":"Olusegun J.","family":"Ilegbusi","sequence":"first","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, FL 32816, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-4461-4423","authenticated-orcid":false,"given":"Godson N.","family":"Brako","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, FL 32816, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8532-4458","authenticated-orcid":false,"given":"Chiranjit","family":"Maiti","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, FL 32816, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jihua","family":"Gou","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, FL 32816, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7471","DOI":"10.1038\/s41598-025-92063-z","article-title":"Tissue Mimicking Hydrogel Foam Materials with Mechanical and Radiological Properties Equivalent to Human Lung","volume":"15","author":"Li","year":"2025","journal-title":"Sci. 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