THE STRING PHASE-TRANSITION IN SHEARING LIQUIDS

Computer simulations revealed a disorder-order phase transition taking place in shearing liquids. Above a certain shear rate the motion of particles becomes organised. This high shear rate structure, the so-called string phase was studied in order to determine optimum arrangements of spherical particles under these conditions. In the high density, infinite shear rate limit where the random thermal motion of the particles can be neglected minimum energy structures were found as functions of density and interaction. We identified these structures and related them to equilibrium arrangements. We also performed nonequilibrium molecular dynamics simulations in order to compare the limit structures to string phase structures simulated at finite shear rates. Finally, we were searching for easily computable state variables capable of indicating this phase transition.