Description du projet
Un nouvel éclairage sur le comportement de l’écoulement des nanofluides
Les nanofluides sont des suspensions colloïdales de particules solides de taille nanométrique dans un fluide de base. Leur capacité à modifier le comportement de leur écoulement sur des surfaces, liée aux forces de structuration internes entre les nanoparticules, est une propriété unique. Il en résulte une meilleure récupération du pétrole par rapport aux solutions de saumure standard. Financé par le programme Actions Marie Skłodowska-Curie, le projet NANOSLIP entend mieux comprendre le comportement des nanofluides à l’interface avec les huiles. Les chercheurs étudieront plus particulièrement, via des techniques de sonde colloïdale, comment les nanofluides à film ultrafin peuvent réduire la traînée en réponse au cisaillement entre un liquide non miscible et une surface solide. Une meilleure compréhension du comportement des nanofluides favorisera leur utilisation dans la récupération du pétrole, la lubrification, la dissipation de la chaleur, l’assainissement des sols, la nanomédecine et la stabilité colloïdale.
Objectif
Nano-fluids (NFs) are colloidal suspensions of nano-species (NS) that are electrostatically or sterically stabilised, with aqueous NFs including nanoparticle suspensions (silica, sulfate latex), polyelectrolytes, and self-assembled structures including micelles, polymersomes and liposomes. NFs are used in many industrial/practical applications, including controlling colloidal assembly of larger nano- and micro-sized species in solution, improving heat flux in industrial processes and solar collectors, reducing friction in oils and greases, enhanced drug delivery and as MRI contrast agents. A unique property of NFs is their modified spreading/flowing behaviour on surfaces due to internal structuring forces between NS, which enables NFs to displace immiscible liquids from surfaces. This enhanced spreading/flowing behaviour has demonstrated enhanced oil recovery compared to standard brine solutions and has been rationalised as due to a reduction of friction at the NF/oil interface. Aside from the presence of a stable nano-thin NF film beneath oil during displacement being confirmed optically via interferometry, there are no experiments to date that have probed this interface directly, and thus the friction/drag reducing properties at the liquid/NF interface remain unexplored. The scientific goal of this proposed project is to gain a better understanding of liquid flow at a liquid/NF interface, in particular, how the presence of an ultrathin film of NFs – with enhanced spreading and internal properties – can reduce drag in response to shear between an immiscible liquid and a solid surface via colloidal probe atomic force microscopy. Understanding this phenomenon will fill the current knowledge gap in the fields of NFs and boundary slip and will have direct impact on current applications of NFs in oil recovery, lubrication, heat dissipation, soil remediation, nanomedicine, and colloidal stability.
Champ scientifique
Programme(s)
Régime de financement
MSCA-IF - Marie Skłodowska-Curie Individual Fellowships (IF)Coordinateur
BS8 1QU Bristol
Royaume-Uni