{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T23:06:59Z","timestamp":1768432019609,"version":"3.49.0"},"reference-count":30,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2017,2,15]],"date-time":"2017-02-15T00:00:00Z","timestamp":1487116800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"UK EPSRC","award":["EP\/K000586\/1"],"award-info":[{"award-number":["EP\/K000586\/1"]}]},{"name":"UK EPSRC","award":["EP\/M021475\/1"],"award-info":[{"award-number":["EP\/M021475\/1"]}]},{"name":"UK EPSRC","award":["EP\/L00030X\/1"],"award-info":[{"award-number":["EP\/L00030X\/1"]}]},{"name":"China NNSF","award":["51506168"],"award-info":[{"award-number":["51506168"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>Micro\ufb02uidic droplet technology has been developing rapidly. However, precise control of dynamical behaviour of droplets remains a major hurdle for new designs. This study is to understand droplet deformation and breakup under simple shear \ufb02ow in con\ufb01ned environment as typically found in micro\ufb02uidic applications. In addition to the Newtonian\u2013Newtonian system, we consider also both a Newtonian droplet in a non-Newtonian matrix \ufb02uid and a non-Newtonian droplet in a Newtonian matrix. The lattice Boltzmann method is adopted to systematically investigate droplet deformation and breakup under a broad range of capillary numbers, viscosity ratios of the \ufb02uids, and con\ufb01nement ratios considering shear-thinning and shear-thickening \ufb02uids. Con\ufb01nement is found to enhance deformation, and the maximum deformation occurs at the viscosity ratio of unity. The droplet orients more towards the \ufb02ow direction with increasing viscosity ratio or con\ufb01nement ratio. In addition, it is noticed that the wall effect becomes more signi\ufb01cant for con\ufb01nement ratios larger than 0.4. Finally, for the whole range of Newtonian carrier \ufb02uids tested, the critical capillary number above which droplet breakup occurs is only slightly affected by the con\ufb01nement ratio for a viscosity ratio of unity. Upon increasing the con\ufb01nement ratio, the critical capillary number increases for the viscosity ratios less than unity, but decreases for the viscosity ratios more than unity.<\/jats:p>","DOI":"10.3390\/mi8020057","type":"journal-article","created":{"date-parts":[[2017,2,15]],"date-time":"2017-02-15T10:09:07Z","timestamp":1487153347000},"page":"57","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Droplet Dynamics of Newtonian and Inelastic Non-Newtonian Fluids in Con\ufb01nement"],"prefix":"10.3390","volume":"8","author":[{"given":"Nikolaos","family":"Ioannou","sequence":"first","affiliation":[{"name":"JamesWeirFluidsLaboratory, DepartmentofMechanical&AerospaceEngineering,UniversityofStrathclyde, Glasgow G1 1XJ, UK"}]},{"given":"Haihu","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Energy and Power Engineering, Xi\u2019an Jiaotong University, Xi\u2019an 710049, China"}]},{"given":"M\u00f3nica","family":"Oliveira","sequence":"additional","affiliation":[{"name":"JamesWeirFluidsLaboratory, DepartmentofMechanical&AerospaceEngineering,UniversityofStrathclyde, Glasgow G1 1XJ, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0683-7050","authenticated-orcid":false,"given":"Yonghao","family":"Zhang","sequence":"additional","affiliation":[{"name":"JamesWeirFluidsLaboratory, DepartmentofMechanical&AerospaceEngineering,UniversityofStrathclyde, Glasgow G1 1XJ, UK"}]}],"member":"1968","published-online":{"date-parts":[[2017,2,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1016\/j.aca.2016.02.006","article-title":"A review on continuous-flow microfluidic PCR in droplets: Advances, challenges and future","volume":"914","author":"Zhang","year":"2016","journal-title":"Anal. 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