11 January, 2010
Soft glasses, rheology and trap models
Abstract
The aim of these lectures is to illustrate how concepts and models developed for molecular and spin glasses can be used to understand soft glasses like emulsions and colloidal suspensions, and in particular their rheology (mechanical behaviour and flow). Subjects to be covered include:
- Introduction to shear rheology: flow curves, linear response (stress relaxation, creep, oscillator shear moduli) and the example of the Maxwell model, nonlinear response and constitutive equation
- Phenomenology of soft glassy rheology
- Trap models: Definition, master equation, glass transition, aging
- Soft glassy rheology model: Including strain degrees of freedom, effective temperature, steady-state predictions (flow curve, moduli), aging properties, memory effects (rejuvenation and over-aging)
- Extensions to tensorial stress and strain
- Effective temperature dynamics and shear banding
References and suggested reading
- P Sollich, Rheological constitutive equation for a model of soft glassy materials. Physical Review E, 58: 738 - 759, 1998.
- S M Fielding, P Sollich and M E Cates. Aging and rheology in soft materials. Journal of Rheology,44: 323-369, 2000.
- M E Cates and P Sollich. Tensorial constitutive models for disordered foams, dense emulsions, and other soft nonergodic materials. Journal of Rheology, 48:193-207, 2004. http://uk.arxiv.org/abs/cond-mat/0307098
- S M Fielding, P Sollich and M E Cates. Shear banding, aging and noise dynamics in soft glassy materials. Soft Matter, 2009.