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Old   August 22, 2012, 08:11
Default Oscillatory flow 101
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Hi all,
I am using CFX to model oscillatory flow in a bifurcation. BC's are inlet with a velocity defined by a trigonometric expression that I entered, outlet with a relative pressure of 0 and wall with no-slip condition. Initial values are zero for all velocities. Transient flow has been selected, and output control to print results every second.
The mesh is a simple octree mesh.
This is a simple situation but it just simply does not work, I was wondering if I am missing something obvious?
Any help would be greatly appreciated,
Andris
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Old   August 22, 2012, 08:33
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Quote:
Originally Posted by Andris View Post
it just simply does not work, I was wondering if I am missing something obvious?
besides describing what it is that doesnt work? We cant help you if you dont give us any more info...
error messages? ccl? solver output?
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Old   August 22, 2012, 09:24
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Hi Lance,
here is the error message

An error has occurred in cfx5solve:
writemms exited with non-zero return code 11

I was wondering if this transient problem has to be done in a similar way to as it is done in the tutorials, i.e. taking initial conditions from a steady state domain?
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Old   August 22, 2012, 09:38
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Here is the geometry I am using,
I readjusted the global initialization to a very small velocity in the y direction,
I get the following error message

ERROR #001100279 has occurred in subroutine ErrAction. |
| Message: |
| Floating point exception: Overflow |
| |
| |
| |
| |
| |
+--------------------------------------------------------------------+

+--------------------------------------------------------------------+
| ERROR #001100279 has occurred in subroutine ErrAction. |
| Message: |
| Stopped in routine FPX: C_FPX_HANDLER |
| |
| |
| |
| |
| |
+--------------------------------------------------------------------+
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Old   August 22, 2012, 10:16
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http://www.cfd-online.com/Wiki/Ansys...do_about_it.3F
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Old   August 22, 2012, 10:21
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thanks for the link, instead of using an expression, I used an excel file, and got a solution, though the solution was very very bad, I am surprised it worked
I was wondering if this transient problem has to be done in a similar way to as it is done in the tutorials, i.e. taking initial conditions from a steady state domain?
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