{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T14:13:21Z","timestamp":1766067201639,"version":"3.48.0"},"reference-count":31,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T00:00:00Z","timestamp":1766016000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, I.P.\/MCTES","award":["UID\/50020\/2025"],"award-info":[{"award-number":["UID\/50020\/2025"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, I.P.\/MCTES","award":["LA\/P\/0045\/2020"],"award-info":[{"award-number":["LA\/P\/0045\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Mathematics"],"abstract":"<jats:p>The increasing global demand for cleaner transportation has intensified the importance of efficient AdBlue\u00ae (AUS32) production, a key chemical in selective catalytic reduction (SCR) systems that reduces nitrogen oxides (NOx) emissions from diesel engines. This work presents a computational fluid dynamics (CFD) simulation study of the urea\u2013water mixing process within a high shear mixer (HSM), aiming to enhance the sustainability of AdBlue\u00ae manufacturing. The model evaluates the hydrodynamic characteristics critical to optimising the dissolution of urea pellets in deionised water, which conventionally requires significant preheating. Experimental validation was conducted by comparing pressure drop simulation results with operational data from an active industrial facility in the United Kingdom. Therefore, this study validates the CFD model against an industrial two-stage Rotor\u2013stator under real operating conditions. The computational framework combines a refined mesh with the k-\u03c9 SST turbulent model to resolve flow structures and capture near-wall effects and shear stress transport in complex flow domains. The results reveal opportunities for process optimisation, particularly in reducing thermal energy input without compromising solubility, thus offering a more sustainable pathway for AdBlue\u00ae production. The main contribution of this work is to close existing gaps in industrial practice and propose and computationally validate strategies to improve the numerical design of HSM for solid dissolution.<\/jats:p>","DOI":"10.3390\/math13244027","type":"journal-article","created":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T13:45:07Z","timestamp":1766065507000},"page":"4027","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["CFD Simulation of a High Shear Mixer for Industrial AdBlue\u00ae Production"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-5564-7038","authenticated-orcid":false,"given":"Ludovic F.","family":"Ascen\u00e7\u00e3o","sequence":"first","affiliation":[{"name":"LSRE-LCM, ALiCE, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"PROMETHEUS, School of Technology and Management (ESTG), Polytechnic Institute of Viana do Castelo, Avenida do Atl\u00e2ntico n\u00b0 644, 4900-348 Viana do Castelo, Portugal"},{"name":"Navistokes Engineering Lda, Rua do Picoto n\u00ba37, 4760-083 Vila Nova de Famalic\u00e3o, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2399-2914","authenticated-orcid":false,"given":"Isabel S. O.","family":"Barbosa","sequence":"additional","affiliation":[{"name":"LSRE-LCM, ALiCE, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1792-2223","authenticated-orcid":false,"given":"Ad\u00e9lio M. S.","family":"Cavadas","sequence":"additional","affiliation":[{"name":"PROMETHEUS, School of Technology and Management (ESTG), Polytechnic Institute of Viana do Castelo, Avenida do Atl\u00e2ntico n\u00b0 644, 4900-348 Viana do Castelo, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9133-2187","authenticated-orcid":false,"given":"Ricardo J.","family":"Santos","sequence":"additional","affiliation":[{"name":"LSRE-LCM, ALiCE, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Buruiana, D.L., Sachelarie, A., Butnaru, C., and Ghisman, V. (2021). Important Contributions to Reducing Nitrogen Oxide Emissions from Internal Combustion Engines. Int. J. Environ. Res. 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