CGNS file from ansys fluent for one way coupled solution with Altair EDEM

Kiran Purushothama Keshavan

Hello,

Is there a tutorial on simulation on fluent and EDEM using a CGNS file to perform one way coupled solution on EDEM?
If not can someone please point out to resources where I can read about how I can import the CGNS and then run the EDEM case on it?

Thanks,
Kiran

PrasadAvilala

Hi Kiran,

CGNS is a neutral format, either fluent or any other cfd software can be used to export velocity field data through CGNS format and in EDEM the velocity field data imported.

You can go through the below tutorial and understand the workflow. Though the below link is for API model you can understand the steps/work flow and use in-built drag and lift models.

 

The below API tutorial is for reference only.

Altair Exchange - EDEM API: Particle Body Force - Field Data Coupling – Choice of Drag Models with Lift Force

 

Thanks,

Prasad A

Kiran Purushothama Keshavan

Hello Prasad,

Thanks for your reply, I have a few questions about the tutorial you've linked.

1.I'm assuming that the presence of the '.dll' file, '.cu' file, field_query_prefs, and 'cgns' file in the directory of the '.dem' file would be good to start my simulation on EDEM?(Would I have to change the name of the .dll and the .cu file to match the name of my simulation deck?)
Do I have to modify any of these files if I had to run my own case with these files in the folder?

2. Can I have wall-shear or pressure values instead of the vorticity.cgns as a CGNS file to show the effect of these quantities on the particle in the domain?
Would I have to change any of the details to account the influence of these quantities on the particle itself?

3. Would the mesh size and the particle matter in this case? For example, in the 2-way coupling, there are a lot of constraints on time step, velocity, relaxation factors etc. would these values still play a role in the simulation on EDEM? (I'm guessing it shouldn't)

4. Can I use CGNS files from a ANSYS Fluent steady state simulation on EDEM field data coupling?

Thanks,
Kiran

 

PrasadAvilala

Kiran Purushothama Keshavan said:

Hello Prasad,

Thanks for your reply, I have a few questions about the tutorial you've linked.

1.I'm assuming that the presence of the '.dll' file, '.cu' file, field_query_prefs, and 'cgns' file in the directory of the '.dem' file would be good to start my simulation on EDEM?(Would I have to change the name of the .dll and the .cu file to match the name of my simulation deck?)
Do I have to modify any of these files if I had to run my own case with these files in the folder?

2. Can I have wall-shear or pressure values instead of the vorticity.cgns as a CGNS file to show the effect of these quantities on the particle in the domain?
Would I have to change any of the details to account the influence of these quantities on the particle itself?

3. Would the mesh size and the particle matter in this case? For example, in the 2-way coupling, there are a lot of constraints on time step, velocity, relaxation factors etc. would these values still play a role in the simulation on EDEM? (I'm guessing it shouldn't)

4. Can I use CGNS files from a ANSYS Fluent steady state simulation on EDEM field data coupling?

Thanks,
Kiran

 

 

 

1).I'm assuming that the presence of the '.dll' file, '.cu' file, field_query_prefs, and 'cgns' file in the directory of the '.dem' file would be good to start my simulation on EDEM?(Would I have to change the name of the .dll and the .cu file to match the name of my simulation deck?)

 

A) Step-1: I would suggest first run the tutorial as it is and understand the simulation steps i.e what is the input data required and what is the drag and lift  model to be chosen and then

Step-2: Same simulation with dll and .cu using in-built physics model you can run the simulation.

The API model is very old and the same physics models are added in to EDEM as a in built Physics models.

Step-3: After above 2 steps go ahead with you're problem statement to run.

2).I'm assuming that the presence of the '.dll' file, '.cu' file, field_query_prefs, and 'cgns' file in the directory of the '.dem' file would be good to start my simulation on EDEM?(Would I have to change the name of the .dll and the .cu file to match the name of my simulation deck?)

 

A) Vorticity is required if you are choosing lift model i feel but if this data not required then please ignore while writing data to .CGNS.

 

3). Would the mesh size and the particle matter in this case? For example, in the 2-way coupling, there are a lot of constraints on time step, velocity, relaxation factors etc. would these values still play a role in the simulation on EDEM? (I'm guessing it shouldn't)

A) Mesh size in EDEM doesn't play any role but Mesh size in CFD will play a major role in accuracy of the results.

 

Regarding time steps typically 20% of Raleigh time step is good enough but if you see instability request you to reduce the time step else 20% of Raleigh time step is good enough.

4) Can I use CGNS files from a ANSYS Fluent steady state simulation on EDEM field data coupling?

 

A) As i said earlier CGNS is a neutral format, Either fluent or Acusolve or StarCCM or any other CFD software data can be exported and imported in EDEM to run the simulation.

 

Thanks,

Prasad A