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Old   December 27, 2012, 15:17
Default Wall shear stress & pressure drop
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Mohammed
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I have problem when I want to draw the wall shear stress or pressure drop in perforated pipe or without perforated pipe at polyline. Why the curve of the figure is coming like a zig-zag not like a line (straight)? I am using CFX-5, RNG k-epsilon model, turbulent flow. My mesh as tetra.
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Old   December 27, 2012, 21:12
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you are going to have to be a bit more specific, I don't know what you mean?
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Old   December 29, 2012, 05:59
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If you already made the polyline which runs along the wall following the perforated profile, you can use this as a location for any of your variable plots. The Chart feature allows x-axis and the y-axis to be selected independently. If you want to plot the x-axis as the linear displacement along the pipe, simply choose the x-axis to be the corresponding coordinate direction (e.g. either X,Y or Z) on your model orientation.

Hope this helps. As Erik suggested above, it is really difficult to know what you mean without any images or a more detailed description.
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Old   December 29, 2012, 13:46
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Quote:
Originally Posted by Crank-Shaft View Post
If you already made the polyline which runs along the wall following the perforated profile, you can use this as a location for any of your variable plots. The Chart feature allows x-axis and the y-axis to be selected independently. If you want to plot the x-axis as the linear displacement along the pipe, simply choose the x-axis to be the corresponding coordinate direction (e.g. either X,Y or Z) on your model orientation.

Hope this helps. As Erik suggested above, it is really difficult to know what you mean without any images or a more detailed description.
Thanks for reply
I thing that happening from the type of element, I am using tetra type not hexa type to do my mesh. I draw today the simple pipe without perforation and mesh it for two kinds of elements and saw the curve at tetra type like a zig-zag but at the type of hexa the curve is normal.
But I faced the difficult when i mesh the geometry by hexa. Please do you have knowledge about how can I do it.
Thanks in advanced.
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Old   December 31, 2012, 02:29
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Quote:
Originally Posted by mohw2002 View Post
Thanks for reply
I thing that happening from the type of element, I am using tetra type not hexa type to do my mesh. I draw today the simple pipe without perforation and mesh it for two kinds of elements and saw the curve at tetra type like a zig-zag but at the type of hexa the curve is normal.
But I faced the difficult when i mesh the geometry by hexa. Please do you have knowledge about how can I do it.
Thanks in advanced.
Please post some images of your chart, meshes or geometry, since any advice or suggestions we provide could be completely wrong if we are left to guess your geometry.
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Old   January 10, 2013, 11:52
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Hi for all
I have one thing at post-CFX:
- Can I import the values of one chart for a case to another case to make a comparison between them? if yes how can I do?
Thanks
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Old   September 1, 2013, 10:42
Default The velocity nera wall of the pipe
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How can I calculate the velocity near the wall to calculate the friction pressure drop and friction factor by using CFX, ANSYS FLUENT14?
My case, perforated pipe (wellbore) length is 1.3m has two section, the first part is perforated and follow by blank section. The pipe draw and meshing it by ICEM-CFD.
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