Hi,

Can someone tell me how to relate the physical variables (real world variables) to the non-dimensional variables in the lattice Boltzmann equations (such as, viscosties, domain length, ime, density, velocities, surface tension,...)? Thanks!

For transient problem, is there a constraint on delta t? (delta t is 1 in LBE, right?)

Pei-Ying Hsieh

Hi, you could read

Naoki Takada, Michihisa Tsutahara Evolution of viscous flow around a suddenly rotating circular cylinder in the lattice boltzmann method Computers & Fluids vol 27 no 7 pp807-828 (1998)

you have to scale the viscosity (related to the relaxation parameter) with the time step and the space increment.