Simon Cox
Click for email addressInstitute of Mathematics and Physics
Aberystwyth University
Phone: +44-(0)1970-622764
Fax: +44-(0)1970-622826
Foam News
December 2009: Simon attended the BSR midwinter meeting at Edinburgh University, and gave a talk on the Rheology of Dry Foams.
September 2009: Doris Stingl (Regensburg) has started a one-semester research project on "The effect of non-uniform container shape on foam drainage".
August 2009: Simon was a co-organiser of "Flow of foams", a workshop held at the Lorentz Centre in the Netherlands, 17-21 August 2009.
August 2009: We advertised for a postdoctoral research associate in Modelling and visualization of complex materials.
July 2009: Our three summer students have now finished their various projects. Francois Boulogne (Physics, Paris) showed how a negative lift arises when foams flow past a fixed, asymmetric, obstacle. It is of course the asymmetry that is important, but Francois was able to quantify this in terms of the curvature of the sides of the obstacle. Sam Spencer (2nd year Maths and Physics) performed drainage and stability experiments on foams, to determine the influence of container dimensions and surfactant concentration on foam lifetime. He showed that the effect of evaporation, even on short time-scales, is much larger than we believed. David Ferguson (2nd year MMath) held a Walter Idris summer bursary to investigate minimal perimeter partitions of triangles. In contrast to previous work, he considered arbitrary triangles, and delineated the topologies of the optimal partitions based on the shape of the triangle.
June 2009: Two A-level students, Jessica Mowatt and Jacob Hebditch, visited the group as part of their work experience: "The time we have spent in Aberystwyth University has been an insightful period into the electrifying world of Physics. Our days consisted of high speed photography of rebounding balls, bursting balloons and more, including the mechanisms of a bumble bee's wings (see videos)! We also used a rheometer to measure various properties of different complex liquids (e.g. mayonnaise, toothpaste), such as viscosity, shear strength and elasticity. The week ended with a tour of the various facilities of the department, which proved an exciting and inspiring event. Overall, the experience has been beneficial in understanding what occurs behind closed laboratory doors and has, in no doubt, increased our interest in pursuing a stimulating and enticing career in research."
April 2009: Simon gave a talk at the British Applied Mathematics Colloquium at the beginning of April in Nottingham on Predicting the shape of bubbles moving through narrow channels. This is joint work with Gennady Mishuris and Denis Weaire (Dublin) which will soon be published in the Proceedings of the Royal Society.
April 2009: The whole group went to Cardiff for the 5th Annual European Rheology Conference. Aled and Tudur presented posters, while Simon co-organised and spoke at a symposium on Interfacial Phenomena, Surfactants and Foams.
April 2009: Simon has been invited to join the council of the British Society of Rheology, and attended his first council meeting in Cardiff.
April 2009: There is a new face in the group: Francois Boulogne is visiting from Paris for three months. He will extend our simulation work on foam flow past obstacles to explore obstacle shapes that are expected to display the phenomenon of negative lift (due to the elasticity of the foam and the asymmetry of the obstacle).
March 2009: Simon travelled to Oslo to give a two-day short course on the Rheology and Structure of High Interface Fluid Systems, with G.G. Fuller (Stanford) and J. Vermant (KU Leuven).
January 2009: Simon travelled to Lisbon at the invitation of Prof. Paulo Teixeira of the Centro de Fisica Teorica e Computacional, Universidade de Lisboa, to give a lecture on "Foams: form and flow". He also pursued collaborative work with Paulo and Prof. M.F. Vaz of Instituto Superior Tecnico, Lisboa. Indeed, while visiting we received the proofs of a joint article on the "Effect of the number of shells on the pressure and energy of two-dimensional free bubble clusters", to appear in Colloids and Surfaces A. We are now introducing controlled topological disorder and investigating its effect in the limit in which the number of bubbles goes to infinity.
October 2008: Simon visited Cape Town, South Africa, to give a plenary at the 2nd Southern African Conference on Rheology. He talked about "Foam rheology in confined geometries: bubble-scale modelling".
September 2008: The foams group hosted a visit by several notable aphrologists, including Weaire (Dublin), Marmottant (Grenoble) and Dollet (Rennes), for informal multi-lateral discussions on numerous projects of mutual interest. These included rheological modelling in the high-velocity limit, higher harmonics in rheometry and experimental investigations of flowing foams.
September 2008: Dr Sian Jones will join the group in September as a PDRA to work on a Procter and Gamble/EPSRC-funded project to investigate the foamability and rheological characteristics of new surfactant mixtures.
September 2008: Congratulations to Tudur for his success in the R M Davies Research Prize competition.
August 2008: Simon gave a Condensed Matter Research Seminar at the University of California at Irvine. Following this, Simon, Aled and Tudur visited Monterey for the XVth International Congress on Rheology, where Simon gave a lecture and everybody else presented posters. Aled Wyn also won an SOR Travel Grant to attend the meeting. Other highlights included the premiere of the INNFM film on "Yield Stress" and two black-footed albatrosses.
July 2008: Simon has been invited to be a specialist advisor for RAE2008 in the area of foam rheology.
July 2008: Simon, Aled and Tudur travelled to the Netherlands for the ninth EuFoam conference, the largest foam meeting in the world. More than one hundred "aphrologists" attended, from both academia and industry. The meeting was hosted by the European Space Agency at ESTEC in the Netherlands. ESA's interest in foams stems from the possibility to generate homogenous aqueous and metallic foams with the use of microgravity research facilities - during processing on earth the liquid in a foam drains out under gravity, leading to a inhomogeneous structure with consequently inhomogeneous properties. Simon gave an invited talk on "Predicting the Bubble-scale Structure and Rheology of Aqueous Foams", while Tudur and Aled presented posters on their PhD work.
May 2008: Tudur Davies has won a Faculty of Science Postgraduate Prize. This will enable him to present a poster on his work on particle sedimentation in foams at this year's EUFoam conference. The conference will be held at ESTEC in the Netherlands at the beginning of July.
Publications
Also see AU's repository: Cadair
C. Raufaste,S.J. Cox, P. Marmottant and F. Graner (2010) Discrete rearranging disordered patterns: Prediction of elastic and plastic behaviour, and application to two-dimensional foams . Phys. Rev. E (submitted).
S.J. Cox, P.I.C. Teixeira, and M.F. Vaz (2010) Simulation of defects in bubble clusters. J. Phys.: Condens. Matter 22:065101. Preprint
S.J. Cox and G. Mishuris (2009) Remarks on the accuracy of algorithms for motion by mean curvature in bounded domains. J. Mechanics of Materials Structures 4:1555-1572. Preprint
M.F. Vaz, P.I.C. Teixeira, F. Graner and S.J. Cox (2009) Effect of the number of shells on the pressure and energy of two-dimensional free bubble clusters. Coll. Surf. A 344:33-36. Preprint
S.J. Cox, D. Weaire and G. Mishuris (2009) The Viscous Froth Model: steady states and the high-velocity limit. Proc. R. Soc. A 465:2391-2405. Preprint
I.T. Davies and S.J. Cox (2009) Sedimenting discs in a two-dimensional foam. Coll. Surf. A 344:8-14. Draft PDF version.
G.N. Greaves, M.C. Wilding, S. Fearn, D. Langstaff, F. Kargl, S. Cox, Q. Vu Van, O. Majerus, C.J. Benmore, R. Weber, C.M. Martin and L. Hennet (2008) Detection of First-Order Liquid/Liquid Phase Transitions in Yttrium Oxide-Aluminum Oxide Melts. Science 322:566-570.
C. Quilliet, S. Ataei Talebi, D. Rabaud, J. Kafer, S.J. Cox and F. Graner (2008) Topological and geometrical disorder correlate robustly in two-dimensional foams. Phil. Mag. Lett. 88:651-660. (Preprint).
S.J. Cox (2007) Simulations of Two-Dimensional Foam under Couette Shear. Preprint.
S.J. Cox and A. Wyn (2008) Localization of topological changes in Couette and Poiseuille flows of two-dimensional foams. AIP Conf. Proc. 1027:836-838. (Draft PDF version)
S.J. Cox, F. Graner and M.F. Vaz (2008) Screening in dry two-dimensional foams. Soft Matter, 4:1871-1878 (Draft PDF version).
S.J. Cox and E. Janiaud (2008) On the structure of quasi-two-dimensional foams. Phil. Mag. Letts. 88:693-701 (Draft PDF version).
S.J. Cox, S. Neethling and H. Wilson (2008) British Society of Rheology mid-winter meeting on The Rheology of Foams and Emulsions. Applied Rheology 18:93-95.
Hutzler, S., Saadatfar, M., van der Net, A., Weaire, D. and Cox, S.J. (2008) The dynamics of a topological change in a system of soap films. Coll. Surf. A 323:123-131. (Draft PDF version).
A. Wyn, I.T. Davies and S.J. Cox (2008) Simulations of two-dimensional foam rheology: localization in linear Couette flow and the interaction of settling discs Euro. Phys. J. E 26:81-89 Draft PDF version.
Raufaste, C., Dollet, B., Cox, S., Jiang, Y. and Graner, F. (2007) Yield drag in a two-dimensional foam flow around a circular obstacle: Effect of liquid fraction. Euro. Phys. J. E 23: 217-228. (Draft PDF version).
Peron, N., Cox, S.J., Hutzler, S. and Weaire, D. (2007) Steady drainage in emulsions: corrections for surface Plateau borders and a model for high aqueous volume fraction. Euro. Phys. J. E 22: 341-351.(Draft PDF version).
Hutzler, S., Weaire, D., Cox, S.J., Van der Net, A. and Janiaud, E. (2007) Pre-empting Plateau: the nature of topological transitions in foam. Europhys. Lett. 77: 28002 (Draft PDF version).
Fortes, M.A., Vaz, M.F., Cox, S.J., and Teixeira, P.I.C. (2007) Instabilities in two-dimensional flower and chain clusters of bubbles. Coll. Surf. A 309:64-70. (Draft PDF version).
Hutzler, S., Cox, S.J., Janiaud, E. and Weaire, D. (2007) Drainage induced convection rolls in foams. Coll. Surf. A 309:33-37. (Draft PDF version).
Cox, S.J. and Whittick, E.L. (2006) Shear modulus of two-dimensional foams: The effect of area dispersity and disorder. Euro. Phys. J. E 21:49-56 (Draft PDF version).
Cox, S.J. (2006) Calculations of the minimal perimeter for N deformable cells of equal area confined in a circle. Phil. Mag. Letts. 86:569-578 (Draft PDF version).
Cox, S.J. (2006) The mixing of bubbles in two-dimensional bidisperse foams under extensional shear. J. non-Newt. Fl. Mech. 137:39-45 (Draft PDF version).
Weaire, D., Hutzler, S., Drenckhan, W., Saugey, A. and Cox, S.J. (2006) The rheology of foams. Progr. Colloid Polym. Sci. 133:100-105.
Cox, S.J., Dollet, B. and Graner, F. (2006) Foam flow around an obstacle: simulations of obstacle-wall interaction. Rheol. Acta. 45:403-410 (Draft PDF version).
Cox, S.J., Alonso, M.D., Weaire, D. and Hutzler, S. (2006) Drainage induced convection rolls in foams - I. Convective bubble motion in a tilted tube. Eur. Phys. J. E 19:17-22 (Draft PDF version).
Saint-Jalmes, A., Cox, S.J., Marze, S., Safouane, M., Langevin, D. and Weaire, D. (2006) Experiments and Simulations of Liquid Imbibition in Aqueous Foams under Microgravity. Microgravity Sci. Tech.. 18:108-111.
Vaz, M.F. and Cox, S.J. (2005) Two-bubble instabilities in quasi-two-dimensional foams. Phil. Mag. Letts.85:415-425 (Draft PDF version).
Saint-Jalmes, A., Marze, S., Safouane, M., Langevin, D., Cox, S. and Weaire, D. (2005) Foam Experiments in the Maxus 6 Sounding Rocket: towards the ISS module. Proc. 17th ESA Symp. European Rockets. ESA Publications Division, Noordwijk, The Netherlands SP-590:573-578.
Hutzler, S., Weaire, D., Saugey, A., Cox, S. and Peron, N. (2005) The physics of foam drainage. Proc. 52nd SEPAWA Congress, Wurzburg, ed. K. Henning, p191-206.
Brunke, O., Hamann, A., Cox, S.J. and Odenbach, S. (2005) Experimental and numerical analysis of the drainage of aluminium foams. J. Phys.: Condens. Matter 17:6353-6362.
Jurine, S., Cox, S.J. and Graner, F. (2005) Dry three-dimensional bubbles: growth-rate, scaling state and correlations. Coll. Surf. A 263:18-26.
Drenckhan, W., Cox, S.J., Delaney, G., Holste, H. and Weaire, D. (2005) Rheology of ordered foams - on the way to Discrete Microfluidics. Coll. Surf. A 263:52-64.
Cox, S.J. (2005) A Viscous Froth Model for Dry Foams in the Surface Evolver. Coll. Surf. A 263:81-89.
Hutzler, S., Cox, S.J. and Wang, G. (2005) Foam drainage in two dimensions. Coll. Surf. A 263:178-183. Draft PDF version
Weaire, D. and Cox, S. (2005) Foams in Microgravity Proc. 21st Intl. Congress Theo. Appl. Mech. W. Gutkowski and T.A. Kowalewski (eds), Warsaw, Poland, 387-394.
Caps, H., Cox, S.J., Decauwer, H., Weaire, D. and Vandewalle, N. (2005) Capillary rise in foams under microgravity. Coll. Surf. A 261:131-134.
Weaire, D., Cox, S.J. and Brakke, K. (2005) Liquid foams - Precursors for Solid Foams. In Cellular Ceramics: Structure, Manufacturing, Properties and Applications, P. Colombo and M. Scheffler (eds). Wiley.
Kern, N., Weaire, D., Martin, A., Hutzler, S. and Cox, S.J. (2004) Two-dimensional viscous froth model for foam dynamics Phys. Rev. E. 70:041411.
Cox, S.J., Neethling, S., Rossen, W.R., Schleifenbaum, W., Schmidt-Wellenburg, P. and Cillliers, J.J. (2004) A theory of the effective yield stress of foam in porous media: the motion of a soap film traversing a three-dimensional pore.Coll. Surf. A 245:143-151.
Cox, S.J., Weaire, D. and Verbist, G. (2004) Comment on "Foam imbibition in microgravity. An experimental study" by H. Caps, H. Decauwer, M.-L. Chevalier, G. Soyez, M. Ausloos and N. Vandewalle. Euro. Phys. J. B 40:119-121.
Cox, S.J., Weaire, D. and Glazier, J.A. (2004) The rheology of two-dimensional foams. Rheol. Acta. 43:442-448.
Vaz, M.F., Cox, S.J. and Alonso, M.D. (2004) Minimum energy configurations of small bidisperse bubble clusters. J. Phys: Condensed Matter. 16:4165-4175.
Cox, S.J., and Graner, F. (2004) Three-dimensional bubble clusters: shape, packing and growth-rate. Phys. Rev. E. 69:031409 (Draft PDF version).
Drenckhan, W., Weaire, D. and Cox, S.J. (2004) The demonstration of conformal maps with two-dimensional foams. Eur. J. Phys. 25:429-438.
Weaire, D., Kern, N., Cox, S.J., Sullivan, J.M. and Morgan, F. (2004) Pressures in periodic foams. Proc. R. Soc. Lond. A 460:569-579.
Cox, S.J., and Verbist, G. (2003) Liquid flow in foams under microgravity. Microgravity Sci. Tech. 14:45-52.
Cox, S.J. and Graner, F. (2003) Large two-dimensional clusters of equal-area bubbles: the influence of the boundary in determining the minimum-energy configuration. Phil. Mag. 83:2573-2584. (Offprint)
Cox, S.J., Vaz, M.F. and Weaire, D. (2003) Topological changes in a two-dimensional foam cluster. Euro. Phys. J. E 11:29-35. (Offprint)
Cox, S.J. and Fortes, M.A. (2003) Properties of three-dimensional bubbles of constant mean curvature. Phil. Mag. Letts. 83:281-287.
Weaire, D., Hutzler, S., Cox, S., Kern, N., Alonso, M.D. and Drenckhan, W. (2003) The Fluid Dynamics of Foams. J. Phys.: Condens. Matter 15:S65-S73. (Offprint)
Cox, S.J., Graner, F., Vaz, M.F., Monnereau-Pittet, C. and Pittet, N. (2003) Minimal perimeter for N identical bubbles in two-dimensions: calculations and simulations. Phil. Mag. 83:1393-1406. (Offprint).
Cox, S.J., Weaire, D. and Vaz, M.F. (2002) The transition from two-dimensional to three-dimensional foam structures. Eur. Phys. J. E 7:311-315. (Preprint)
Weaire, D., Cox, S.J. and Graner, F. (2002) Uniqueness, Stability and Hessian eigenvalues for two-dimensional foam structures. Eur. Phys. J. E7:123-127. (Preprint).
Weaire, D., Cox, S.J., Hutzler, S. and Bradley, G. (2001) Foams in microgravity. J. Phys. IV France 11:Pr6-213-220.
Weaire, D., Banhart, J. and Cox, S.J. (2001) Cellular Metals: New Materials, New Applications, New Science. Proc. Materials Week 2001.
Weaire, D., Cox, S.J. and Banhart, J. (2001) Methods and models of metallic foam fabrication. In D. Hui (ed) Proc. 8th Ann. Intl. Conf. Composites Engng. p977-978.
Cox, S.J., Bradley, G. and Weaire, D. (2001) Modelling metallic foam formation. In Cellular Metals and Metal Foaming Technology, MIT-Verlag, Bremen, p99-104.
Cox, S.J. and Weaire, D. (2001) Comment on "Free-drainage of aqueous foams: container shape effects on capillarity and vertical gradients". Europhys. Lett.55:445-446
Cox, S.J., Bradley, G., Hutzler, S. and Weaire, D. (2001) Vertex corrections in the theory of foam drainage. J. Phys: Condens. Matter 13:4863-4869.
Cox, S.J., Bradley, G. and Weaire, D. (2001) Metallic foam processing from the liquid state: the competition between solidification and drainage. Eur. Phys. J. AP 14:87-97.(PDF)
Cox, S.J. and Cooker, M.J. (2001) The Pressure Impulse in a Fluid Saturated Crack in a Sea Wall. Coastal Eng. 42:241-256. (Offprint)
Banhart, J., Baumgartner, F., Cox, S.J., Kronberg, B., Langevin, D., Odenbach, S., Weaire, D. and Wubben, T. (2001) Development of advanced foams under microgravity. Proc. 1st Intl. Symposium on Microgravity Research and Applications in Physical Sciences and Biotechnology, Sorrento, Italy, p589-596.
Weaire, D., Verbist, G., Cox, S.J. and Hutzler, S. (2001) Frontiers of the Physics of Foams. Proc. 1st Intl. Symposium on Microgravity Research and Applications in Physical Sciences and Biotechnology, Sorrento, Italy, p103-108.
Hutzler, S., Cox, S.J., Weaire, D. and Wilde, P.J. (2000) New developments in foam drainage. In Foams, emulsions and their applications, MIT-Verlag, Bremen, p5-12.
Cox, S.J., Alonso, M.D., Hutzler, S. and Weaire, D. (2000) The Stokes experiment in a foam. In Foams, emulsions and their applications, MIT-Verlag, Bremen, p282-289.
Cox, S.J., Weaire, D., Hutzler, S. and Verbist, G. (2000) Drainage phenomena in uniform and non-uniform foams. In Foams, emulsions and their applications, MIT-Verlag, Bremen, p266-273.
Cox, S.J., Weaire, D., Hutzler, S., Murphy, J., Phelan, R., and Verbist, G. (2000) Applications and Generalisations of the Foam Drainage Equation. Proc. R. Soc. Lond. A 456:2441-2464.
Cox, S.J. and Cooker, M.J. (2000) Potential Flow Past a Sphere Touching a Tangent Plane. J. Eng. Math. 38:355-370.
Phelan, R., Weaire, D., McMurry, S. and Cox, S.J. (1999) The Deformation of Soap Film Junctions by Applied Forces. Phil. Mag. Lett. 79:887-896.
Cox, S.J. and Cooker, M.J. (1999) The Motion of a Rigid Body Impelled By Sea-Wave Impact. Appl. Ocean Res. 21:113-127. (Offprint)
Cox, S.J. and Cooker, M.J. (1998) The Effect of Wave Impact on a Body in the Breaker Zone. Proc. 13th Intl. Workshop on Water Waves and Floating Bodies, Delft, The Netherlands. p15-20.
Cox, S. (1997) The County's second Black and White Warbler. Norfolk Bird Club Bull. 22:47-49.