[Rimzy]

Hello,

I am doing simulation of solar loading on evacuated tube. After developing geometry and mesh, when I opened the setup i received this error:
'Received fatal signal(segmentation fault)'
The same model successfully opened yesterday in setup when i inserted some model conditions but after that PC got hanged then i switched off PC. But today i am trying from last 3 hours its giving the same problem. Can anyone please help me? Thanks

[vinerm]

Hi Muhammad

It appears that there are incomplete interfaces. Recommended would be to open Meshing, ensure that there are not contacts under connections, generate the mesh, and export it. Set up the case again.

If you wish to continue with WB, it would still be advisable to remove contacts and regenerate the mesh.

[djamila77]

Dear all;
I am trying to simulate convection and masse transfer in cavity
I don't know how to applied it in fluent (masse transfer ) and how I can add the concentration equation to the convectif equation.
please help me
Best

[vinerm]

What type of mass transfer exists in your case? Is it from one phase to another phase? Is it due to any reaction? Or is it not the mass transfer but convection of component(s) from one location to another, such as, smoke movement?

[Rimzy]

Originally Posted by vinerm

Hi Muhammad

It appears that there are incomplete interfaces. Recommended would be to open Meshing, ensure that there are not contacts under connections, generate the mesh, and export it. Set up the case again.

If you wish to continue with WB, it would still be advisable to remove contacts and regenerate the mesh.

Thank you for help.
Do you mean that i should suppress all contacts under connections?

[vinerm]

Instead of suppression, delete the contacts. However, you have to ensure that in the Meshing tool when you click on Geometry, it shows only one part that contains all the bodies. If the bodies are listed individually under Geometry branch then you should go back to modeling tool to ensure that bodies have shared topology. Use Form New Part in DM and Share in Workbench tab in SCDM.

[Rimzy]

Originally Posted by vinerm

Instead of suppression, delete the contacts. However, you have to ensure that in the Meshing tool when you click on Geometry, it shows only one part that contains all the bodies. If the bodies are listed individually under Geometry branch then you should go back to modeling tool to ensure that bodies have shared topology. Use Form New Part in DM and Share in Workbench tab in SCDM.

Ok. I will. currently i have 7 parts and 10 bodies under geometry in Mesh tool. By deleting all contacts would not affect results?

[vinerm]

If you have any moving mesh in your domains, then you have to keep multiple parts. Otherwise, you should have one part and all the bodies should belong to the same part. You can use different names for all the bodies in case you want to assign different materials or source terms or some other parameters. But by ensuring that all bodies belong to same part, you will have conformal mesh and simulation will run very smooth.

[Rimzy]

Originally Posted by vinerm

If you have any moving mesh in your domains, then you have to keep multiple parts. Otherwise, you should have one part and all the bodies should belong to the same part. You can use different names for all the bodies in case you want to assign different materials or source terms or some other parameters. But by ensuring that all bodies belong to same part, you will have conformal mesh and simulation will run very smooth.

As i have fluid inside the solid tubes so for fluid domain we always have moving mesh?

[vinerm]

The motion of the fluid is an outcome of the solution of conservation equations. Mesh motion is used only if there is a solid body moving or if the fluid body has a solid motion, i.e., fluid body moving with respect to the inertial frame, e.g., there is motion of fuel in the fuel tank of a vehicle, however, the fuel tank is also moving with respect to the ground. Otherwise, you do not need any mesh motion or frame motion.

[djamila77]

Originally Posted by vinerm

What type of mass transfer exists in your case? Is it from one phase to another phase? Is it due to any reaction? Or is it not the mass transfer but convection of component(s) from one location to another, such as, smoke movement?

Hi Vinerm;

In my case I have reaction,
but I don't understand the third case that you said;

can I ask something how to add the mass diffusion coefficient for the solidification case, do I need an UDF.

Thanks

[vinerm]

It appears that there are two threads running in parallel within this one.

Djamila, mass transfer could occur because of reactions, e.g., C becoming CO. Or it could be phase change, such as evaporation, condensation, or solidification. Or it could be combination. As far as solidification is concerned, you do not require a multiphase model. There is a separation solidification-melting model in Fluent. It is not multiphase.