Enhanced single-node lattice Boltzmann boundary condition for fluid flows

We propose a procedure to implement Dirichlet velocity boundary conditions for complex shapes that use data from single node only, in the context of lattice Boltzmann method. Two ideas are at base this approach. The first is generalize geometrical description combining bounce-back rule with interpolations. second enhance them by limiting interpolation extension proximity boundary. Despite its local nature, resulting method exhibits second-order convergence field and shows similar or better accuracy than well-established Bouzidi's scheme curved walls [M. Bouzidi, M. Firdaouss, P. Lallemand, Phys. Fluids 13, 3452 (2001)]. Among infinite number possibilities, we identify several meaningful variants method, discerned their approximation nonequilibrium terms coefficients. For each one, provide two parametrized versions produce viscosity independent steady state. proves be suitable simulate moving rigid objects surfaces following either body dynamics prescribed kinematic. Also, it applies uniformly without modifications whole domain any shape, including corners, narrow gaps, other singular geometry.