| Popis: |
A numerical method to simulate concentrated colloidal suspensions has been developed. It is based on a combination of the fluctuating lattice Boltzmann equation method for the flow of the fluid with molecular dynamics for the suspended particles; its main advantage is that it scales linearly with the number of particles. In extensive tests, the method has been shown to reproduce fully the time-dependent many-body hydrodynamic interactions. Brownian motion of the particles can be simulated via random fluctuations in the fluid stress tensor, thus corresponding to the physical origin of the motion. The short-term and long-time dynamics of concentrated suspensions have been investigated via this method. Outstanding agreement between the numerical results and recent experimental data has been obtained for the short-time dynamics. The analysis of the long-time data has proven somewhat more difficult due to the finite-size effects of the simulation. Finally, the motion of an isolated colloidal particle confined between two plane walls has been studied and the relevant transport coefficients have been obtained. This new method to simulate colloidal suspensions represents a significant improvement over more conventional algorithms and it is expected to provide in the future further insight into both equilibrium and non-equilibrium properties of concentrated suspensions. |
