[caltantz]

Hello everyone,

Although I have been following the forum for some time, this is my first post.

I have very recently switched my interest from combustion to multiphase flows. I intend to study dense particle-gas flows (fluidized bed gasifiers) and I am interested in open source software to do it.

I came across the twoPhaseEulerFoam solver but unfortunately my C++ knowledge is still very limited and I have some questions concerning it.

From what I have understood by following the code itself and the forum, the solver uses two approaches to describe the particle interactions, the powder modulus approach and the kinetic theory of granular flows approach.

I) Concerning the powder modulus, if I am not wrong, the code uses the ppProperties to calculate the solids pressure. How are the solids shear stresses taken into account, if at all?

II) When using the ppProperties, the alphaMax criterion is not fulfilled even if the packing limiter is employed (parameters taken from Bouilard et al., AIChe 1989). Has anybody experienced this problem before?

III) The same problem occurs when I use the KTGF for the more detailed description of the particle collisions. The solution to this problem would be to use an extremely small time step? (The simulations conducted up to now employ dt=10^-6). Are there any other possible solutions? Am I doing something wrong?

I am using the version 2.0.1 and I try to simulate toy problems without employing turbulence modeling.

Thank you very much