CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   CFX (https://www.cfd-online.com/Forums/cfx/)
-   -   a simulation with rotation and vibration (https://www.cfd-online.com/Forums/cfx/122867-simulation-rotation-vibration.html)

liuzexiang September 6, 2013 20:22

please give me some advice!!

ghorrocks September 8, 2013 06:26

I have nothing to add beyond what I have already said. Until you consider my previous suggestions I see no point making more suggestions.

liuzexiang September 10, 2013 23:21

Quote:

Originally Posted by ghorrocks (Post 450466)
I have nothing to add beyond what I have already said. Until you consider my previous suggestions I see no point making more suggestions.

the rotation simulation have done with the single fluid,but when the fluid is set the multiphase flow, the mistake appear as follow:
Run mode: partitioning run

Host computer: MK-PC (PID:788)
Job started: Wed Sep 11 10:45:40 2013

Details of error:-
----------------
Error detected by routine PSHDIR
CDRNAM = ../../JCONT
CRESLT = NONE

Current Directory : /FLOW/ALGORITHM/ZN1/SYSTEM/EQUATIONS/JCONT_FL2/TERM1

ERROR #001100279 has occurred in subroutine ErrAction. |
| Message: |
| Stopped in routine MEMERR

An error has occurred in cfx5solve: |
| |
| The ANSYS CFX partitioner exited with return code 1.

ghorrocks September 11, 2013 06:09

This error says you missed a fundamental part of the multiphase setup -but I cannot tell exactly which. I would check the multiphase setup again.

You could also post the output file with the CCL and error included.

liuzexiang September 11, 2013 12:57

1 Attachment(s)
Quote:

Originally Posted by ghorrocks (Post 451095)
This error says you missed a fundamental part of the multiphase setup -but I cannot tell exactly which. I would check the multiphase setup again.

You could also post the output file with the CCL and error included.

Thank you for your reply. there is the output in the attachment.
the mistake is : No data source for Workspace, cannot monitor Solver data.

liuzexiang September 11, 2013 13:21

the rotation simulation is done when i set both of the symmetry area of the tool domain and fluid domain are domain interface and the rotational periodicity is set in the Interface Model. the connecting areas between tool domain and fluid domain, workpiece domain and fluid domain is set frozen rotor in the Frame change/Mixing Model. The electrimagntic model is set in the tool domain ,fluid domain and workpiece domain respectively. when the fluid contains only the brine,the simulation is finished without error, but when the gas (air at 298k) is contained in the fluid, the mistake appear such as above. i check the set in the simulation for many time, but i can not find the reason. Please tell why.
Anther question :
I do not know the really situation as the simulation, in my opinion,when the tool rotats in the fluid domain, that is to say it stir the fluid,so there must be change in the pressure and the velocity of the fluid. But i can not find the change in the simulation,so i can not believe the result of the simulation. Maybe the set of the domain interface is wrong,such as the Mass And Momentum, i try the Free Slip wall or No slip wall. but the result is no change.
Is the method for the rotation simulation right?

liuzexiang September 11, 2013 13:48

1 Attachment(s)
there is the pressure of monitor point in the fluid domain.

ghorrocks September 11, 2013 18:42

This is a very complex model and I do not have time to debug it for you.

All I can recommend is to build the simulation up piece by piece. Can you run a cavitation model without electrics, rotation and moving mesh? Once that is working, add the physics one bit at a time to build up to the full model.

liuzexiang September 11, 2013 20:19

Quote:

Originally Posted by ghorrocks (Post 451230)
This is a very complex model and I do not have time to debug it for you.

All I can recommend is to build the simulation up piece by piece. Can you run a cavitation model without electrics, rotation and moving mesh? Once that is working, add the physics one bit at a time to build up to the full model.

Thank you for your advice. i will do the simulation piece by piece. but i can not find the reason for error. there is few books about the ANSYS cfx, can you give me same advice or others. my Email is lzx_527.student@sina.com

liuzexiang September 14, 2013 09:00

why ?
 
3 Attachment(s)
why is the result?
the rotation simulation is done and the tool domain is set as rotation with speed 600rpm
the explation of the pictures.
the model (picture 1): 1 is the interface of the tool domain and the fluid domain at the inside of the hole of the tool , the set:interface model: General Connection,Frezon Rotor; the interface side in fluid domain is set No slip wall, and the wall velocity is rotating wall :-600 rpm
2 is the interface of the tool domain and the fluid domain at the outside of the hole of the tool, the set is the same as 1;
4 is the interface of the tool domain and the fluid domain at the bottom of the domain. the set is the same as 1;
3 is the interface of the workpiece domain and the fluid at the side of the hole of the workpiece, the set interface model:General Connection,Frezon Rotor; the interface side in fluid domain is set No slip wall, but the wall velocity is set as 0 rpm;
5 is the interface of the workpiece domain and the fluid at the bottom of the hole of the workpiece, the set is the same as 3.
the quesetion is :
1. when the velocity contour is gained ,why is zero(the blue) for the velocity at the surrounding of the tool ;(the blue) in picture 2
2. when the velocity coutour is gained,there is no change for the velocity in the direction. in my opinion maybe is the swirl, and the direction of the velocity should be changed.
the tool: outside diameter 1.2mm, the inside diameter:0.8mm
the hole in the workpiece :diameter:1.6mm

liuzexiang September 14, 2013 09:24

is the set of the rotation wrong? or for there is no change for the too small tool in the fluid simulation.

other questions:
1.such as this kind of rotation simulation,the tool domain is set as fluid in many similar example. what is the difference between the fluid domain and the solid domain. the simulation when the tool domain is set as the fluid domain, the result is different, and the velocity surrounding the tool domain is not zero. why?
2.Is the CFX suitable for the simulation with two-phase flow and electromagnetic model? i try for many times, but failure.
Thank you very much!

ghorrocks September 15, 2013 06:53

I say again - This is a very complex model and I do not have time to debug it for you.

But I can see in your contours that it looks very blocky. This suggests you have a very coarse mesh. You will not get very useful results with such a coarse mesh, a far finer mesh is required.

liuzexiang September 15, 2013 10:12

Quote:

Originally Posted by ghorrocks (Post 451795)
I say again - This is a very complex model and I do not have time to debug it for you.

But I can see in your contours that it looks very blocky. This suggests you have a very coarse mesh. You will not get very useful results with such a coarse mesh, a far finer mesh is required.

Thank you for your reply. As the mesh is finer, the computer can not work. So, i just simulation with the coarse mesh. But i do not know the method for the simulation is right?

Lance September 16, 2013 02:50

Quote:

Originally Posted by liuzexiang (Post 451811)
Thank you for your reply. As the mesh is finer, the computer can not work. So, i just simulation with the coarse mesh. But i do not know the method for the simulation is right?

Then get a bigger computer. There is no point in doing such a complex simulation if you cannot resolve the flow. You are only wasting your time.

liuzexiang September 16, 2013 08:12

Quote:

Originally Posted by Lance (Post 451927)
Then get a bigger computer. There is no point in doing such a complex simulation if you cannot resolve the flow. You are only wasting your time.

Yes. i will try!


All times are GMT -4. The time now is 11:20.