Multispecies approach implemented in the code is based on the paper "Multi-species Lattice Boltzmann Model and Practical Examples. Short Course material Pietro Asinari PhD."
Equlibrium distribution function for multispecies is given in the paper as
where, for and , is molecular weight for species .
is given as
Relaxation time is given as
A semi-implicit Lattice Boltzmann equation is given as,
Variable transformation presented in above paper involves three steps
In back tranformation, to compute feq we need and can be computed directly from g
where as the computed by solving the linear system of equation given below
use for optimized routine
!West u_n(1) = - uxstar(s) !south u_n(2) = - uystar(s) !bottom u_n(3) = - uzstar(s) !east u_n(4) = uxstar(s) !north u_n(5) = uystar(s) !top u_n(6) = uzstar(s) !bottom south u_n(7) !top south u_n(7) !bottom north u_n(7) !top north u_n(7) !bottom west u_n(7) !bo u_n(7) u_n(7) u_n(7) u_n(7)