Deegan group

Cornstarch finger

Holes in Shear Thickening Fluid

"Shear thickening fluids" are fluids whose viscosity increases when they are sheared.  A classic example is a mixture of water and cornstarch;  this is a fascinating substance to simply play with.  A newly discovered property of these fluids is their ability to sustain vertical structures like fingers and holes when shaken vertically.     An example of these is shown on the right, and a movie of this phenomenon is available here. The goal of this project is to explain this phenomenon. 


R.D. Deegan, "Stress hysteresis as the cause of persistent holes in particulate suspensions", Phys. Rev. E. 81, 036319 (2010).

F. Merkt, R.D. Deegan, D. Goldman, E. Rericha, & H.L. Swinney, “Persistent holes in a fluid”, Phys. Rev. Lett. 92 184501 (2004).

Updated May 11, 2010