Brian P. Tighe

Assistant Professor (Universitair Docent)
Process & Energy Laboratory
TU Delft

Office: P&E Building Rm 120
Tel: +31 (0)15 27 81103
Email: b.p.tighe (at) tudelft.nl

Mail Address:

Delft University of Technology
Process & Energy Laboratory
Leeghwaterstraat 44
2628 CA Delft
The Netherlands

I study the deformation and flow of amorphous solids and complex fluids -- some examples are foams, emulsions, colloidal suspensions, and granular media. I am particularly interested in the dynamics of materials close to yielding or unjamming, the point where a material loses rigidity due to shear or decompression.

Blurbs:

• Damped random spring networks. We show how to construct the diverging length scale that governs physics both above and below isostaticity and at finite frequency, and how to use this length scale to predict response.
• Packings at finite pressure, yet unstable to shear. We explain -- and resolve! -- one of the dirty little secrets of jamming: not all that's "jammed" is really so.
• Relaxations and rheology near jamming. We calculate, for the first time, the complex shear modulus of soft sphere packings near jamming. Our results explain the appearance of shear thinning in complex fluids like foams and emulsions (published in Physical Review Letters).
• Flow on the brink of jamming. Our analytical model predicts that the rich rheology of soft sphere packings in shearing flow is governed by distance to the jamming transition, and is confirmed via numerical simulations (published in Physical Review Letters). Recently confirmed in experiment!
• The rheology of foams is nonlocal. Liquid foams in a Couette geometry violate the conventional picture of yield stress fluids, but a simple model incorporating nonlocal effects describes their flow (published in Europhysics Letters).
• The Force Network Ensemble is a model for stresses in static granular packings. We recently contributed a review article to the jamming theme issue of Soft Matter. The issue provides a nice snapshot of the field.
• We recently presented the first calculation of the equation of state of the Force Network Ensemble and demonstrated that stress fluctuations become increasingly large as the system is brought closer to an isostatic state.
• Other work on the FNE includes our explanation of the form of the local pressure distribution (published in Physical Review Letters and featured in the Condensed Matter Journal Club) and an exploration of two different canonical ensembles in mechanical equilibrium (published in JSTAT).
• Slides from talks at the Lorentz Center workshop "Statistical Mechanics of Static Granular Media" are available now. Thanks to all the participants!
• Try the Jammotron!
  

Disclaimer: If you found this page with a search engine, you may be wondering whether I'm the Brian Tighe with all the knives. I'm not.