Hello,
I intend to use MFIX-DEM for Lunar Regolith Granular flow simulation.
Now, lunar environment has reduced gravity and near vacuum environment.
Is there any tutorial model available to simulate similar flows with MFIX-DEM ?
Please let me know.
Thanks and Regards,
Debashis
Hi Debashis, welcome to the MFiX forum.
I don’t know of a relevant tutorial, but I think that this should be achievable. Note that gravity is an input parameter in the “Model setup” pane, so you should be able to simulate lunar gravity:
As for the near-vacuum environment you have a few choices. You could specify a very low pressure in the initial conditions pane:
Or you could specify a low density in the fluid setup pane,
Or, as the tooltip indicates, you could treat the lunar atmosphere as vacuum, turning off the fluid solver completely. This will speed up your simulation.
The difficulties I image are that (a) you probably want to simulate a large number of particles, so the simulation will be slow (especially if you don’t have access to a compute cluster for DMP jobs). and (b) you may want to use non-spherical particle models, which run slower than the basic DEM sphere. I suggest you start with a fairly low number spherical particles, and ramp up the complexity of your model from there.
Please let us know if you get any good results, this sounds like an interesting problem.
– Charles
Hello,
Thank you very much for the reply and the explanations. I will try to follow them to set up my model.
I will definitely post a message if the model works.
The second problem I am interested in is flow and particle simulation in Dry Powdered Inhaler (DPI).
Is MFIX-DEM suitable for that ? It will involve turbulent flow as well. What are the available turbulence models in MFIX ?
The lunar Regolith flow will have no fluid flow, only granular solid. But DPI will involve both flow and particles. I am also attaching this paper that explain flow and particle modeling in DPI.
Zheng-et-al-2021-Flow_and_Particle_Modelling_of_Dry_Powder_Inhalers.pdf (2.7 MB)
I look forward to hearing from you.
Thanks and Best Regards,
Sincerely,
Debashis
Hi Debashis
In general it’s better to start a new topic for additional questions, it helps us keep track of which topics have been marked ‘solved’.
I do not have time to study the Zhang paper in detail. It’s up to you to determine whether MFiX is suitable for this application. The available turbulence models in MFiX are the mixing-length (algebraic) and k-epsilon models. This can be seen in the MFiX GUI
and there is a little more information in the user manual, https://mfix.netl.doe.gov/doc/mfix/24.4/html/model_setup/setup.html
Hello Sir,
Thank you very much for your reply.
I will certainly put a new topic if I have additional questions.
Thank you for your reply.
I will follow up with a new topic.
Thanks and Best Regards,
Sincerely,
Debashis
