Micro & Nano Flows for Engineering
The micro & nano flows group is a research partnership between the Universities of Warwick and Edinburgh, and Daresbury Laboratory. We investigate gas and liquid flows at the micro and nano scale (where conventional analysis and classical fluid dynamics cannot be applied) using a range of simulation techniques: molecular dynamics, extended hydrodynamics, stochastic modelling, and hybrid multiscaling. Our aim is to predict and understand these flows by developing methods that combine modelling accuracy with computational efficiency.
Targeted applications all depend on the behaviour of interfaces that divide phases, and include: radical cancer treatments that exploit nano-bubble cavitation; the cooling of high-power electronics through evaporative nano-menisci; nanowire membranes for separating oil and water, e.g. for oil spills; and smart nano-structured surfaces for drag reduction and anti-fouling, with applications to low-emissions aerospace, automotive and marine transport.
EPSRC Programme Grant in Nano-Engineered Flow Technologies
Our work is supported by a number of funding sources (see below), including a 5-year EPSRC Programme Grant (2016-2020). This Programme aims to underpin future UK innovation in nano-structured and smart interfaces by delivering a simulation-for-design capability for nano-engineered flow technologies, as well as a better scientific understanding of the critical interfacial fluid dynamics.
We will produce software that a) resolves interfaces down to the molecular scale, and b) spans the scales relevant to the engineering application. As accurate molecular/particle methods are computationally unfeasible at engineering scales, and efficient but conventional fluids models do not capture the important molecular physics, this is a formidable multiscale problem in both time and space. The software we develop will have embedded intelligence that decides dynamically on the correct simulation tools needed at each interface location, for every phase combination, and matches these tools to appropriate computational platforms for maximum efficiency.
This work is strongly supported by nine external partners (see below).
- “Nano-Engineered Flow Technologies: Simulation for Design across Scale and Phase” EPSRC Programme Grant EP/N016602/1 01/16-12/20 (£3.4M)
- “The First Open-Source Software for Non-Continuum Flows in Engineering” EPSRC grants: EP/K038427/1 K038621/1 K038664/1 07/13-06/17 (£0.9M)
- “Multiscale Simulation of Interfacial Dynamics for Breakthrough Nano/Micro-Flow Engineering Applications” ARCHER Leadership Project 11/15-10/17 (£60k in supercomputer computational resource)
- “Skating on Thin Nanofilms: How Liquid Drops Impact Solids” Leverhulme Research Project Grant 08/16-08/19 (£146k funding a 3-year PDRA)
- Airbus Group Ltd
- Bell Labs
- European Space Agency
- Jaguar Land Rover
- National Physical Laboratory
- Oxford Biomedical Engineering (BUBBL)
- TotalSim Ltd
- Waters Corporation
Latest news and blogs
Jason Reese has been elected Fellow of the American Physical Society (APS) upon the recommendation of the APS Division of Fluid Dynamics. The number of APS Fellows elected each year is limited to no more than one half of one percent of the total membership, so this is a prestigious recognition of Prof Reese’s outstanding contributions to the physics of fluids.
The citation from the APS recognises Prof Reese “for original contributions to multiscale fluid dynamics research, unique work in rarefied gas dynamics, pioneering hybrid modelling, and simulation methods for flows at the micro- and nanoscales.”
The American Physical Society was founded in 1899 “to advance and diffuse the knowledge of physics”. It publishes more than a dozen scientific journals, including the prestigious ‘Physical Review’ and ‘Physical Review Letters’, and organises more than twenty science meetings each year. The APS conducts extensive programs in education, public outreach, and media relations; APS divisions and topical groups cover all areas of physics research. Forums reflect the interests of its over 53,000 international members in broader issues, and sections are organised by geographical region.
Jun gave an invited talk at Institute of Mechanics, Chinese Academy of Sciences on January 4th, 2017. His talk was titled "Molecular simulation and multiscale modelling of nonequilibrium and noncontinuum flows" (in Chinese: 非平衡和非连续流的分子统计模拟与多尺度计算), and was given in front of audiences numbering about 50. The topics include his recent works on droplets and previous works on rarefied gas dynamics.
Dr Stephen M. Longshaw, Research Fellow, Daresbury Laboratory
Stephen will be giving a talk at the international conference on parallel, distributed, grid and cloud computing (or PARENG) conference at the University of Pécs (Hungary) in late March 2017.
This is the fifth edition of the conference series where he will be talking about some of the HPC aspects of code coupling at scale for multi-scale and multi-physics applications, as well as looking towards the concept of the digital product and how code coupling will play its part.
Jesse Pritchard , PhD Student, University of Warwick
Check out this video showing how liquid droplets, upon reaching some critical velocity, can have their shape 'frozen' upon impacting a solid surface coated with a superhydrophobic powder. These experiments were carried out by J. Marston et. al. at the King Abdullah University of Science and Technology, who have written multiple articles discussing the results of their experiments.
Dr David Stephenson , Research Fellow, University of Warwick
Here is an interesting article (and video) on the shrinking instability of toroidal droplets. Toroidal droplets are inherently unstable due to surface tension and seek to minimise their surface area for a given volume: i.e. they want to transform into spherical droplets. Using PIV, they experimentally determine the internal flow field as the droplets shrink and observe that the cross-sections significantly deviate from circular during the process, flattening in the inside regions of the torus. By measuring the experimental velocities at the droplet boundary, which have both tangential and radial components, these observations are then accounted for by theoretically solving the Stokes equations using the stream function in toroidal coordinates.
Dr James Sprittles, University of Warwick
It's always intriguing to see how other people view your research. According to the University of Warwick's graphics team, this is what I do:
The GIF shows that when a liquid spreads over a solid it must displace a microscopic air film whose height is comparable to the mean free path in the gas. Incorporating this physics into a dynamic wetting framework, by solving the Boltzmann equation, is the subject of my recent article in Physical Review Letters.
Along with the Letter, Warwick put out a short Press Release whose success can be tracked using Altmetric, a citation score for press coverage. I've also just written a short piece for The Conversation.
Writing these articles aimed at the public has been challenging as a lot of rigour/citation/humbleness is removed by the Editors, but I hope it will at least attract some attention to our Group's work in multiscale and multiphysics fluid dynamics.