This is a stability test for the KBC model [1].
Despite the grid's low resolution, the solver avoids spurious secondary vortices in accordance with reported results [2].
The plots are in lattice units.
This study case uses the multi direct-forcing IB-LBM [3, 4] to simulate the interaction between the fluid and a cylinder fixed in place. The plots are in lattice units.
A colour-gradient model with a multi-relaxation-time (MRT) collision operator is used to simulate a multiphase flow following [5].
The intended study case is a multiple-mode Rayleigh-Taylor instability [6]; however, further refinement is required so that the heavy (red) and light (purple) fluid dynamics exhibit the characteristic profiles reported in the literature.
The fluid simulation consists of a constant velocity inlet and outlet, a no-slip boundary condition at the bottom (including the rectangle), and a specular top.
An additional distribution function models the sediment concentration. The advection velocity is obtained at each time step from the fluid in a one-way coupling
[3, 7].
This example is a pressure driven flow with bounce back conditions at the top and bottom boundaries to model no-slip walls. Another example uses gravity as the driving mechanism. The plots are in lattice units.
References
Luo, K.H., Fei, L. and Wang, G., 2021. A unified lattice Boltzmann model and application to multiphase flows. Philosophical Transactions of the Royal Society A, 379(2208), p.20200397.
Bosch, F., Chikatamarla, S.S. and Karlin, I., 2015. Entropic multi-relaxation models for simulation of fluid turbulence. ESAIM: Proceedings and Surveys, 52, pp.1-24.
Timm, K., Kusumaatmaja, H., Kuzmin, A., Shardt, O., Silva, G. and Viggen, E., 2016. The lattice Boltzmann method: principles and practice. Cham, Switzerland: Springer International Publishing AG.
Kang, S.K. and Hassan, Y.A., 2011. A comparative study of direct-forcing immersed boundary-lattice Boltzmann methods for stationary complex boundaries. International Journal for Numerical Methods in Fluids, 66(9), pp.1132-1158.
Ba, Y., Liu, H., Li, Q., Kang, Q. and Sun, J., 2016. Multiple-relaxation-time color-gradient lattice Boltzmann model for simulating two-phase flows with high density ratio. Physical Review E, 94(2), p.023310.
He, X., Chen, S. and Zhang, R., 1999. A lattice Boltzmann scheme for incompressible multiphase flow and its application in simulation of Rayleigh-Taylor instability. Journal of computational physics, 152(2), pp.642-663.
Morrison, H.E. and Leder, A., 2018. Sediment transport in turbulent flows with the lattice Boltzmann method. Computers & Fluids, 172, pp.340-351.