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We present a numerical model for dynamic simulation of colloidal particles attached to a fluid interface. A new coupling method is proposed for combining Newtonian dynamics for colloidal particles and the lattice Boltzmann method for fluid phases so as to account for the wetting properties of particle surfaces. With this feature, capillary interaction of colloidal particles, in addition to electrostatic and hydrodynamic interactions, can be simulated.For the validation of the proposed model, we perform numerical simulations of the steady flow around a square array of cylinders, the transient dynamics of a moving particle in the quiescent solvent, as well as the contact angle of a colloidal particle attached to the multi-component fluid interface. Further, we apply the current model to simulate capillary interactions between two colloidal particles at a fluid interface. Effects of the relevant physical parameters on the dynamics of the particles, in particular, wettability and gravity, are investigated.

The lattice Bhatnagar-Gross-Krook modeled uid has an unchangeable unit Prandtl number. A simple method is introduced in this letter to formulate a exible Prandtl number for the modeled uid. The eectiveness was demonstrated by numerical simulations of the Couette ow.

We develop a mesoscopic model for fluid-fluid-solid contact-line motions in the framework of the multi-component lattice Boltzmann model proposed by Gunstensen et al. of immiscible fluid, Phys. Rev. A 43 (1991) 4320-4327]. Regarding a solid wall as a motionless and undeformable fluid, this model can treat both fluid-fluid and fluid-solid interfaces in a unified way. In this research, we investigate fundamental characteristics of our model, such as the dependency of the slip velocity against the contact angles, and the dynamic contact angles against the static contact angles, and compare the simulation results with experimental observation in a qualitative sense.