This package contains a LAMMPS implementation of a background Lattice-Boltzmann fluid, which can be used to model MD particles influenced by hydrodynamic forces. Details are described in these two papers: Mackay, F. E., Ollila, S.T.T., and Denniston, C., Hydrodynamic Forces Implemented into LAMMPS through a lattice-Boltzmann fluid, Computer Physics Communications 184 (2013) 2021-2031. Mackay, F. E., and Denniston, C., Coupling MD particles to a lattice-Boltzmann fluid through the use of conservative forces, J. Comput. Phys. 237 (2013) 289-298. See the doc page for the fix lb/fluid command to get started, and see brief descriptions of other fixes below, each of which have their own doc page. There are example scripts for using this package in examples/USER/lb. IMPORTANT NOTE: This package can only be used if LAMMPS is compiled with MPI (i.e. the serial makefile should not be used to compile the code). Also, several of the test examples provided make use of the rigid fix. Therefore, this should be included in the LAMMPS build by typing "make yes-rigid" prior to the usual compilation (see the "Including/excluding packages" section of the LAMMPS manual). The creators of this package are as follows: Frances Mackay University of Western Ontario fmackay@uwo.ca Dr. Colin Denniston University of Western Ontario cdennist@uwo.ca -------------------------------------------------------------------------- Fixes provided by this package: fix_lb_fluid.cpp: fix used to create the lattice-Boltzmann fluid on a grid covering the LAMMPS simulation domain. fix_momentum_lb.cpp: fix used to subtract off the total (atom plus fluid) linear momentum from the system. fix_pc.cpp: integration algorithm for individual atoms. fix_rigid_pc_sphere.cpp: integration algorithm for rigid spherical collections of atoms. fix_viscous_lb.cpp: fix to add the fluid force to the atoms when using a built-in LAMMPS integrator.