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-   -   toposet or setFields!! (http://www.cfd-online.com/Forums/openfoam-pre-processing/125890-toposet-setfields.html)

Salam-H November 2, 2013 22:49

toposet or setFields!!
 
Hi every one, I hope someone can help. I am new on OpenFoam, I have model a funnel filled with water and then let the water to flow. I tried to create the geometry by using blockmesh however I coudn't do that , then I had to do it through Salome Meca and export it to Openfaom which works fine. when I tried to model a cube every thing seems good , but when I try with Funnel I get problems , I believe my problem is related to the level of fluid in the funnel as I don't know how to identify the VOF in the funnel, can someone help me please, I really appreciate your comments. If you think you need to see my files please let me know.

Best regards,

Salam

wyldckat November 3, 2013 06:27

Greetings Salam and welcome to the forum!

The important details are:
  1. What is the absolute position and size of your funnel?
  2. What settings are you using in "setFieldsDict"?
Best regards,
Bruno

Salam-H November 3, 2013 14:15

Setfields
 
Quote:

Originally Posted by wyldckat (Post 460324)
Greetings Salam and welcome to the forum!

The important details are:
  1. What is the absolute position and size of your funnel?
  2. What settings are you using in "setFieldsDict"?
Best regards,
Bruno

Dear wildcat,
I really appreciate your help. I believe by the absolute position you mean the vertexes, I have the following points for the funnel.

Cylinder part :
(x Y Z) or (X1 X2 X3)
(2.38 0 0)
(-2.38 0 0)
(0 2.38 0)
(0 -2.38 0)

the hight of the cylinder is (50.4) so the points are
(2.38 0 50.4)
(-2.38 0 50.4)
(0 2.38 50.4)
(0 -2.38 50.4)
the second part (conical shape ) :
(-76 0 305)
(76 0 305)
(0 -76 305)
(0 76 305)

if you connect the points above you will get a funnel .

so the dimensions are :

cylinder : diameter : 4.7 mm
Higher ( 50.4mm)

cone : diameter1 D1 4.7 mm
cone : diameter2 D2 152 mm
Higher 254.6 mm

the total higher 305 mm

the size of the funnel is 1.5 litters.

Please if you want to see the funnel click on this link (http://www.p-wholesale.com/cn-pro/19...ic-694430.html)

2. In the setFiledsDict I want to specify the volume of fluid in the funnel, I have have my funnel to be filled with a liquid let us say Water , I don't know how to tell the program the amount of water that I have in my funnel. I used targetVolumeToCell option , it seems good but when I try to do the reconstruction it fails. I have been working on this problem nearly month and still cannot model it properly.

I really appreciate your help and than you so much for the reply.

best regards,

salam

wyldckat November 3, 2013 18:02

1 Attachment(s)
Hi Salam,

Attached is an example schematic of how you should think about the settings to be defined in "setFieldsDict". In essence, you need to pre-calculate the level at which it should filled at the start, then define a box as the 2 red dots indicate.
A good example for this is the tutorial "multiphase/interDyMFoam/ras/sloshingTank3D", which defines that the default value for the "alpha1" field is 0 and that inside the box, it's 1.

But it will only set to 1 the existing mesh cells, therefore I'm assuming you only have the mesh for the inside of the funnel...

Best regards,
Bruno

Salam-H November 3, 2013 18:24

Setfields
 
Quote:

Originally Posted by wyldckat (Post 460374)
Hi Salam,

Attached is an example schematic of how you should think about the settings to be defined in "setFieldsDict". In essence, you need to pre-calculate the level at which it should filled at the start, then define a box as the 2 red dots indicate.
A good example for this is the tutorial "multiphase/interDyMFoam/ras/sloshingTank3D", which defines that the default value for the "alpha1" field is 0 and that inside the box, it's 1.

But it will only set to 1 the existing mesh cells, therefore I'm assuming you only have the mesh for the inside of the funnel...

Best regards,
Bruno

Hi there,

Thanks a lot for your valuable comments. I have been using damBreak case and modified as much as I could. Do you think if I send you the files would you be able to run it on your pc and see where my mistake is. I get errors in running parallel and when change the time steps in contolDict it gets fixed but I don't understand why.Other than that I get another error when I run reconstruction . can I send you the files please?

best regards,

salam

wyldckat November 4, 2013 18:08

Hi Salam,

Sorry, I won't be able to have a look into your files in the next 2 weeks.

But in the meant time, it would be helpful if you could provide the following information:
  1. What is the contents of your "setFieldsDict" file?
  2. What is the complete error message that reconstructPar is giving you?
  3. What is the output of when your simulation is running, which leads to a crash? More specifically the Courant Number values in the last 3 iterations before it crashes?
Best regards,
Bruno

Salam-H November 4, 2013 18:53

2 Attachment(s)
Quote:

Originally Posted by wyldckat (Post 460542)
Hi Salam,

Sorry, I won't be able to have a look into your files in the next 2 weeks.

But in the meant time, it would be helpful if you could provide the following information:
  1. What is the contents of your "setFieldsDict" file?
  2. What is the complete error message that reconstructPar is giving you?
  3. What is the output of when your simulation is running, which leads to a crash? More specifically the Courant Number values in the last 3 iterations before it crashes?
Best regards,
Bruno

Dear Bruno,

Thank you so much for the reply, I thought I was left alone but I was wrong, you are the most helpful person I ever meet on internet. to answer your questions I have included two attachments to this , one is my setfieldsDict the other is the error massage I get,, Just to let you know that I have setted up my setfields the way you told me to do in order to identify the VOF. I have my funnel in a cube, and yet it doesnt work. I also tried to do it like , targetVolumetoCell in which I dont have to have the funnel inside a cube , I can view it on Paraview , but i get problems when i run it in parallel, I will also include attachments of the SetFieldsDict and the error in my next quote so you can see which one is better for my case. by the way I have modified the dambreak case.

Courant Number mean: 2.0309795e-07 max: 48.235083

Best regards,

Salam

Salam-H November 4, 2013 19:12

2 Attachment(s)
These attachments for the funnel without cube.
Courant Number mean: 7.0038059e-08 max: 18.824966



Best regards,

Salam[/QUOTE]

wyldckat November 9, 2013 18:01

Greetings Salam,

According to this thread: http://www.cfd-online.com/Forums/cfd...lp-please.html - I'm assuming you are already getting help on this question you have?

Best regards,
Bruno

Salam-H November 10, 2013 18:31

Quote:

Originally Posted by wyldckat (Post 461346)
Greetings Salam,

According to this thread: http://www.cfd-online.com/Forums/cfd...lp-please.html - I'm assuming you are already getting help on this question you have?

Best regards,
Bruno

Hi Bruno,

Thanks for your quote, and thank you for the effort it meant a lot to me. Yes that is right I am getting some help regarding my case.

best regards,

salam


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