multiphase model guide
 

Hi everybody ,
I'm going to prepare presentation about multiphase model and discrete phase model so I need tips and recommendations about how can I start this because I have no Idea or if anybody can tell me about it by posts and guide me in a right way,
( my mail nassertmt@gmail.com)
if there is any tutorials please let me see it

Tips for a very stiff DPM model ?
 

The concepts behind multiphase and discrete models are quite different. so If it was me doing the presentation I would keep them separate after introducing them.

key points might be:
Multiphase models:
- use a euler-euler approach.
- "mixture" models apply the same velocity fields to both flows.
- mixture models are good for where this is an appropriate approximation - say, very small particles or droplet that follow the flow stream easily
- "euler-euler" models use a velocity field for each phase.
- more rigorous that mixture.
- good for eg: fluidised beds.
- both models model the second phase as a continuum - (imagine something more like a bag of flour than a bag of gravel)
Discrete models:
- good for where dilute conditions, where particles occupy <10% of the volume fraction.
- also where particles separate from the flow due to inertia: eg cyclones.
- model the flow first, then you add an ingection of the particles.
- euler-lagrange, so instead of having two contiuous phases, the fluid is a continuum, and the particles exist as points in space
- so the fluid is first computed over each discrete distance (the mesh),
- the particle trajectory is computed over each time-step, on average about five time steps per mesh element, as the particle moves from its initial release.
- two-way coupling of DPM then also adds source terms to the fluid to account for the particle movement.

I do appreciate your concern thank you very much