Kinetic theory of discontinuous shear thickening

A simple kinetic theory to exhibit a discontinuous shear thickening (DST) is proposed. The model includes the collision integral and the friction from environment as well as a thermostat term characterized by $T_{\rm ex}$. The viscosity of this model is proportional to $\dot\gamma^2$ for large shear rate $\dot\gamma$, while it is Newtonian for low $\dot\gamma$. The emergence of the DST is enhanced for lower density and lower nonzero $T_{\rm ex}$.Comment: 4 pages, 2 figures, Powders and Grains 2017 (in press

Pattern dynamics of cohesive granular particles under a plane shear

We perform three dimensional molecular dynamics simulations of cohesive granular particles under a plane shear. From the simulations, we found that the granular temperature of the system abruptly decreases to zero after reaching the critical temperature, where the characteristic time $t_{\rm cl}$ is approximately represented by $t_{\rm cl} \propto (\zeta-\zeta_{\rm cr})^{-\beta}$ with the dissipation rate $\zeta$, the critical dissipation rate $\zeta_{\rm cr}$ and the exponent $\beta \simeq 0.8$. We also found that there exist a variety types of clusters depending on the initial density and the dissipation rate.Comment: 4 pages, 5 figure

Kinetic theory for dilute cohesive granular gases with a square well potential

We develop the kinetic theory of dilute cohesive granular gases in which the attractive part is described by a square well potential. We derive the hydrodynamic equations from the kinetic theory with the microscopic expressions for the dissipation rate and the transport coefficients. We check the validity of our theory by performing the direct simulation Monte Carlo.Comment: 22 pages, 11 figure