fredo490 
August 29, 2012 10:26 
Need Confirmation  Eulerian solver for tiny particules
Hi everyone, it would be nice if somebody can give me some confirmations on the general aspect of my algorithm and the "code" that follows (especially the translation of the equations). I want to setup an unsteady Eulerian solver to compute the behavior of tiny particles in a fluid (only the fluid impact the particules motion through the drag).
Nomenclature :
 volume fraction of the particles
 velocity of the particles
 function of the relative Reynolds number
 time respond of the particle
 velocity of the fluid
Continuity equation :
Momentum equation
The algorithm I have in mind :
1) setup a "phi_alpha" flux equal to
2) initialize this flux in the createfield with:
Code:
"linearInterpolate(alpha)*linearInterpolate(u) & mesh.Sf()"
3) solve the continuity equation using the following code:
Code:
fvScalarMatrix cEqn
(
fvm::ddt(alpha)
+ fvc::div(alpha_phi)
);
cEqn.solve()
4) update the flux phi_alpha with:
Code:
alpha_phi = cEqn.flux();
5) compute the relative Reynolds number, the function and
6) solve the momentum equation using:
Code:
fvVectorMatrix uEqn
(
fvm::ddt(alpha, u)
+ fvm::div(alpha_phi, u)
==
fRe / Tau * alpa * (V – u)
);
uEqn.solve()
My questions are:
i) I'm not sure of the step 4... I kind of reproduce the simpleFoam code. Is there any documentation somewhere about the command ".flux" ?
ii) I'm not sure of the translation of the momentum equation step 6. Do I need to use a specific formulation for the source term ? Does the solver identify the last "u" by itself ?
Thank you in advance for reading this.
