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Geometry, Meshing, CFD Fluid Flow, Extrusion, Open Curves, and Solids
Posted 27 juil. 2014, 01:13 UTC−4 Fluid & Heat, Computational Fluid Dynamics (CFD), Geometry, Materials, Mesh, Studies & Solvers Version 4.4 2 Replies
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Hello,
First, I am completely new to such simulation, have never used Pro/E, Solid Works, etc.
Next, I am modeling turbulent fluid flow through a jet boat droop snoot and nozzle with proprietary geometry.
Initially, I only had "boundaries" since I extruded everything with closed curves. I had to do this because of the proprietary geometry in the nozzle. I must be able to select the internal surfaces and apply materials.
When I wanted to add water, I noticed that I needed an interior "solid." The problem is that a solid extrusion does not allow me to properly materialize my proprietary geometry in my nozzle. As such, I only extruded the droop snoot, which is prior to the nozzle, as a solid, selected the inner part, and materialized it as water. Also, I could select it as inlet.
Since my nozzle did not have a "solid" interior, I could not select it as an outlet. Also, I could not apply the material of water to the void volume of the nozzle.
To complicate matters, my meshing meshed the droop snoot interior, the boundary, which is metal, and the perimeter of my model geometry, but not the void volume of my nozzle. Also, there is a small cylindrical section between the droop snoot and the nozzle that was not extruded as a solid so the same problems with meshing and materializing inner volume with water applies to the cylinder as well.
I am currently simulating, and it appears to be converging, but I really believe my results will not be an accurate representation of my geometry for turbulent flow through the entire union. Especially since the mesh does not include the inner volume (void flow volume) of my cylinder and nozzle.
Therefore, my question is:
How does does one mesh an "open" volume that is enclosed by a boundary? Do I have to extrude it as a solid? If so, how can I ensure that my inner geometry can be materialized as a metal or any other material when I can no longer select it because of the solid extrusion? Yes, the inner nozzle geometry does separate the inner solid of the nozzle if I do extrude it as a solid, so I can select each inner solid volume, but I cannot select the inner geometry to materialize it.
To me, it seems that one would be able to select an "edge" of an entrance boundary surface and make it an 'inlet," the edge of a an exit boundary that is a part of a "union" and make it an "outlet," and then select the same edges after selecting water as a material. Then, the water would automatically be continuous from inlet edge to outlet edge and enclosed by a materialized boundary.
Currently, I am afraid my model will only calculate numerical points throughout the volume of the droop snoot and not the the volume of the cylinder and nozzle. This would not be an accurate model of fluid flow.
First, I am completely new to such simulation, have never used Pro/E, Solid Works, etc.
Next, I am modeling turbulent fluid flow through a jet boat droop snoot and nozzle with proprietary geometry.
Initially, I only had "boundaries" since I extruded everything with closed curves. I had to do this because of the proprietary geometry in the nozzle. I must be able to select the internal surfaces and apply materials.
When I wanted to add water, I noticed that I needed an interior "solid." The problem is that a solid extrusion does not allow me to properly materialize my proprietary geometry in my nozzle. As such, I only extruded the droop snoot, which is prior to the nozzle, as a solid, selected the inner part, and materialized it as water. Also, I could select it as inlet.
Since my nozzle did not have a "solid" interior, I could not select it as an outlet. Also, I could not apply the material of water to the void volume of the nozzle.
To complicate matters, my meshing meshed the droop snoot interior, the boundary, which is metal, and the perimeter of my model geometry, but not the void volume of my nozzle. Also, there is a small cylindrical section between the droop snoot and the nozzle that was not extruded as a solid so the same problems with meshing and materializing inner volume with water applies to the cylinder as well.
I am currently simulating, and it appears to be converging, but I really believe my results will not be an accurate representation of my geometry for turbulent flow through the entire union. Especially since the mesh does not include the inner volume (void flow volume) of my cylinder and nozzle.
Therefore, my question is:
How does does one mesh an "open" volume that is enclosed by a boundary? Do I have to extrude it as a solid? If so, how can I ensure that my inner geometry can be materialized as a metal or any other material when I can no longer select it because of the solid extrusion? Yes, the inner nozzle geometry does separate the inner solid of the nozzle if I do extrude it as a solid, so I can select each inner solid volume, but I cannot select the inner geometry to materialize it.
To me, it seems that one would be able to select an "edge" of an entrance boundary surface and make it an 'inlet," the edge of a an exit boundary that is a part of a "union" and make it an "outlet," and then select the same edges after selecting water as a material. Then, the water would automatically be continuous from inlet edge to outlet edge and enclosed by a materialized boundary.
Currently, I am afraid my model will only calculate numerical points throughout the volume of the droop snoot and not the the volume of the cylinder and nozzle. This would not be an accurate model of fluid flow.
2 Replies Last Post 31 juil. 2014, 12:54 UTC−4
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Posted:
1 decade ago
If you have a closed volume that is not filled in you can convert it to a 'solid'. Add a 'convert to solid' node to your geometry node and choose as the input objects all the surfaces that enclose your volume. Build, and you will now have a domain in the volume which can be selected for physics.
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Posted:
1 decade ago
Thanks for the reply Pieter.
Yeah, I already tried to convert it to a solid. That did not work. Oddly enough, all extruded as a solid when I extended all parabolic surfaces a certain distance beyond the circle/cylinder edge. Still, such extension caused so many problems with meshing.
To get all solids extruded and successful meshing with no errors, I changed the range of the parabolic parametric equations to be on the interior of the circle, I added four short parametric lines where each line intersected with the merged parabolic surfaces on one end and the line of the circle/cylinder on the other end. After do that, I had no problems with meshing.
Currently, I am extruding as a solid, meshing with no errors, and computing, but my CFD model is not converging. Any advice?
Yeah, I already tried to convert it to a solid. That did not work. Oddly enough, all extruded as a solid when I extended all parabolic surfaces a certain distance beyond the circle/cylinder edge. Still, such extension caused so many problems with meshing.
To get all solids extruded and successful meshing with no errors, I changed the range of the parabolic parametric equations to be on the interior of the circle, I added four short parametric lines where each line intersected with the merged parabolic surfaces on one end and the line of the circle/cylinder on the other end. After do that, I had no problems with meshing.
Currently, I am extruding as a solid, meshing with no errors, and computing, but my CFD model is not converging. Any advice?