  Galilean invariance is a fundamental property; however, although the lattice
Boltzmann equation itself 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.
