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LB2D_Prime

Copyright (C), 2005, Michael Sukop and Danny Thorne

RELEASE_NOTE_04052005_01

New stuff:

 1. Added parameter "bc_sigma_walls". This toggles enforcement of concentration
    boundary conditions on walls. It only works on walls that are on the sides
    (north,south,east,west) of the domain. Do not use it if you need solids
    elsewhere in the domain! More robust support for concentration boundary
    conditions on solids is pending.

 2. Generalized the buoyancy mechanism. As usual, setting buoyancy to 1 will
    cause solute induced buoyancy effects (with the Inamuro sigma component).
    Now, buoyancy can also be set to -1, which will cause temperature
    induced buoyancy effects. (Set buoyancy to 0 to turn off buoyancy effects.)

 3. Two example multiphase flow problems. One single component and one
    multicomponenet.  See ./in/params_scmp.in and ./src/flags_scmp.h for the single
    component example and see ./in/params_mcmp.in and ./src/flags_mcmp.h for the
    multicomponent example. To use an example, copy the .in and .h files to
    ./in/params.in and ./src/flags.h and recompile. For the .in file, you can
    alternatively include a different file name on the command-line, e.g.

     >> ./lb2d_prime.exe params_scmp.in

    will use params_scmp.in instead of params.in.

Notes:

 1. Having sigma component boundary conditions on all four sides gives rise to
    a some badness at the corners (especially for tau close to .5) which is
    unaddressed in this version.

 2. This version is packages with a little example of flow through a horizontal
    pipe with concentration boundaries on the walls as well as on the inflow
    and outflow. There is gravity in the negative y-direction. Viscosity and
    diffusion are fairly low, due to tau[0] and tau[1] being set to .57. Notice
    the instability at the north-west corner. This goes away for larger tau,
    but the buoyancy effects become less interesting. It blows up when tau gets
    much closer to .5.