I am having severe problems trying to get ready a CGP-Simulation. Step by step:
1.- my very first problem is to close my tank when I generate the mesh. Even increasing the number of cells it seems it is still open and I guess this is my problem for converging my first step (inlet-outlet, single phase flow water simulation).
I attached my geometry. tank_2023-03-28T141538.987412.zip (57.8 MB)
2.- If it runs, I need to include a rotor inside the tank, which has to rotate around 1450 RPM! Rotation is the next issue. But I will try by myself first.
QUESTION: how can I visualize internal (volumetric) cells in my domain?
Can you please attach your stl file “tank.stl” ?
Did you check the normal vectors in your stl file? Please attach a snapshot of your mesh and describe what you mean by “still open”
You will have to create a group of particles to represent the rotor and impose a velocity on these particles. Please take a look at the screefeeeder dem tutorial.
Hi Jeff,
first of all, I appreciate the time you spend having a look of my simulation case.
In the meantime I have already visualized the mesh under Paraview and what I meant with open mesh is actually closed . Unfortunatelly I am getting a bit dissapointed since even a simple one-phase flow without any moving part nor particles is not converging. Let me explain it:
The main idea is actually to simulate something very similar to the geometry I attache here:
1.- The final goal is to test MFIX for CFD-DEM simulations of wet grinding using CGP.
2.- Before moving any rotor or including any particle, I need first to check whether the CFD simulation for the incompressible fluid (rho=1050 kg/m³, visc= 0.00105 Pas) works with a mass flow rate up to 1 kg/s in a characteristic system (domain) with a volume up to 60 L.
3.- The next step is to rotate what I call rotor (STL movable) with a relatively high velocity (25 rps). This could be an issue. If everything works,
4.- I will try to include particles (rho=6050 kg/m³, d=0.0005 m) using CGP. <— This will take time.
But coming back to my current problem, I just want to simulate a simple single-phase flow through the tank with an inlet (mass flow) and an outlet (pressure outlet). The rotor is in the file but for the very first simulation I did inlcude it. So I read some topics in the Forum I have tried many different things: reduce the dt, increase mesh resolution, change some numerics and still the simulation is not converging, actually it does not start!!.
I know you (Jeff) and Charles @cgw recommend first to try and try before asking in the Forum, since you are (I am sure) really busy, but I have already checked many things and I got stuck.
I will really appreaciate any suggestion or hint to move forwards.
. Unfortunatelly I am getting a bit dissapointed since even a simple one-phase flow without any moving part nor particles is not converging. Let me explain it:
