OpenLB – Open Source Lattice Boltzmann Code Forums on Lattice Boltzmann Methods General Topics Lattice Boltzmann Method (material properties)

Viewing 3 posts - 1 through 3 (of 3 total)
• Author
Posts
• #7155
H.Yu
Participant

Hi all,
I’m just starting out and studying the Lettice Boltzmann method. However, as I was researching, a few questions came to my mind.

What I’m curious about is the velocity, the viscosity coefficient, Reynolds.

1.
For air in general (Temperature = 293K)
density = 1.2 [kg/m^3]
kinematic viscosity = 1.825 * e^-5 [kg/ms]
Reynolds number = ((density*U*L)/kinematic viscosity) [-]

2.
Lattice Boltzmann Method
C_s (speed of sound)
C_s = (1/sprt(3))*((delta X)/(delta t))
dynamic viscosity = c_s^2 *(relaxation_time – ((delta t) / 2)) <<< (Chapman Enskog eq)

I saw the contents. Which of the first and second is suitable for the Lattice Boltzmann Method?

#7156
mathias
Keymaster

The Reynolds number = ((U*L)/kinematic viscosity) [-] as always. Just consider LBM as a solver vor the incompressible Navier Stokes Equation, speaking about Re. It can also be seen as solver of other equations.

#7157
H.Yu
Participant

Thank you!

Viewing 3 posts - 1 through 3 (of 3 total)
• You must be logged in to reply to this topic.