Galilean invariant fluid–solid interfacial dynamics in lattice Boltzmann simulations

Galilean invariance is a fundamental property; however, although the dynamics of lattice Boltzmann equation in the hydrodynamic limit is Galilean invariant, this property is usually not taken into account in the treatment of the fluid–solid interface. Here, we show that consideration of Galilean invariance in fluid–solid interfacial dynamics can greatly enhance the computational accuracy and robustness in a numerical simulation. Surprisingly, simulations are so vastly improved that the force fluctuation is very small and a time average becomes unnecessary.