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Problems with FSI set up and solve. 3D Model of a thin walled collapsible tube with laminar flow
Posted May 23, 2012, 5:51 p.m. EDT Version 4.0a 1 Reply
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Hi everyone,
I am currently attempting to model a thin-walled collapsible (elastic) tube with with water flowing through it. For a project I have created a physical model of the system and am creating this model to match the material properties and dimensions (If you look at the model I am sorry the geometries are in inches). The long tube will be held rigid at the 2 ends.
I added 3 physics to my Model: Laminar Flow, Solid Mechanics, and Fluid-Structure Interaction.
I added 2 geometries: The first was a long, thin solid cylinder which I used for the Laminar flow physics. Next I created a long thin-walled "surface" cylinder that sits just outside of the internal, liquid cylinder.
For laminar flow I was able to create and run the model with no problems with water as the fluid and inlet velocity of 2m/s.
The solid mechanics I only selected the 4 parts of the external cylinder, put in my elastic material properties, and set the top and bottom face of the tube walls in "fixed constraint 1".
With the FSI I attempted to follow some PDFs from the model library, but I couldn't find any very closely related. I do not know if it is possible to take the 2 other physics and reference them into the FSI or if I need to define everything in the FSI. If it is possible to take a look at what I did I am not sure how to proceed.
thank you, I appreciate any and all help.
I am currently attempting to model a thin-walled collapsible (elastic) tube with with water flowing through it. For a project I have created a physical model of the system and am creating this model to match the material properties and dimensions (If you look at the model I am sorry the geometries are in inches). The long tube will be held rigid at the 2 ends.
I added 3 physics to my Model: Laminar Flow, Solid Mechanics, and Fluid-Structure Interaction.
I added 2 geometries: The first was a long, thin solid cylinder which I used for the Laminar flow physics. Next I created a long thin-walled "surface" cylinder that sits just outside of the internal, liquid cylinder.
For laminar flow I was able to create and run the model with no problems with water as the fluid and inlet velocity of 2m/s.
The solid mechanics I only selected the 4 parts of the external cylinder, put in my elastic material properties, and set the top and bottom face of the tube walls in "fixed constraint 1".
With the FSI I attempted to follow some PDFs from the model library, but I couldn't find any very closely related. I do not know if it is possible to take the 2 other physics and reference them into the FSI or if I need to define everything in the FSI. If it is possible to take a look at what I did I am not sure how to proceed.
thank you, I appreciate any and all help.
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1 Reply Last Post May 24, 2012, 1:12 a.m. EDT
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Posted:
1 decade ago
Hi
you are overdoing it there, either you chooose strucftural and laminar flow (+ALE) and you couple all equations between the physics yourself (a good exercice), OR you choose FSI that is a precooked physics combining all three previously mentioned. But you should not mix all up.
Always check the list of dependent variables, none same should repeat !
But to begin with its worth to start one physics at the time and use forces to mimic the effects of the others. Once all run correctly it's quickly done to combine them all into a NEW FSI model
--
Good luck
Ivar
you are overdoing it there, either you chooose strucftural and laminar flow (+ALE) and you couple all equations between the physics yourself (a good exercice), OR you choose FSI that is a precooked physics combining all three previously mentioned. But you should not mix all up.
Always check the list of dependent variables, none same should repeat !
But to begin with its worth to start one physics at the time and use forces to mimic the effects of the others. Once all run correctly it's quickly done to combine them all into a NEW FSI model
--
Good luck
Ivar