[dan]

I get one queation in the dambreak tutorial of interFoam.
The setFieldsDict are shown below:
regions
(
boxToCell
{
box (0 0 -1) (0.1461 0.292 1);

fieldValues
(
volScalarFieldValue gamma 1
);
}
);


What does "box (0 0 -1) (0.1461 0.292 1)" mean?

In this case ,I don't see anything related to (0 0 -1) and (0.1461 0.292 1).
Could anyone help me,thanks?

[hartinger]

It specifies two opposite points of a box. All cells within that box are selected. It is used to set the void fraction gamma, in order to pile up a lot of water to be splash around.

markus

[eugene]

"box (0 0 -1) (0.1461 0.292 1)"
defines a rectangular prism aligned with the coordinate system with one point (minimum x, y and z) at (0 0 -1) and another point (maximum x, y and z) at (0.1461 0.292 1).

[dan]

Thank you all. But something confused me is why is "box (0 0 -1) (0.1461 0.292 1)" in this case.
eg:
convertToMeters 0.146
0.1461*0.146=0.0213 is not the physical size of water column.
So does 0.292,1,and -1.
Could anyone help me,thanks?

[hartinger]

The 'convertToMeters' in blockMeshDict is only used inside the 'blockMesh' mesh-generator. x=0.1461 and y=0.292 is the 'top-right' corner of the water column in physical space. The other coordinates are just chosen to be bigger for convenience

markus

[dan]

Thanks,I already know it. There is a geometry figure in the uer guide U-55, it is different with the simulated case. So I am just a little confused. Thank you.

[ronaldo]

Originally Posted by eugene

"box (0 0 -1) (0.1461 0.292 1)"
defines a rectangular prism aligned with the coordinate system with one point (minimum x, y and z) at (0 0 -1) and another point (maximum x, y and z) at (0.1461 0.292 1).

Please could you tell me how can i set the makeCellSets file "boxToCell" is case?

Thank you in advance

[avillamizarh]

Originally Posted by dan

Thank you all. But something confused me is why is "box (0 0 -1) (0.1461 0.292 1)" in this case.
eg:
convertToMeters 0.146
0.1461*0.146=0.0213 is not the physical size of water column.
So does 0.292,1,and -1.
Could anyone help me,thanks?

I have a question. Why the zmin is -1 and zmax is 1?. Thanks

[Parisa_Khiabani]

I have 2 questions about setFields. I was partially answered based on the the following post:

http://www.cfd-online.com/Forums/ope...ell-means.html

However, my questions are:

1- How the minimum and maximum corners are determined?

2- Why zmin and zmax are -1 and +1, as exactly the last forumer aske?

I appreciate if you help me,

Parisa

[wyldckat]

Quick answer, based on previous answers of mine:

1. Originally Posted by wyldckat

   Have a look into this file: https://github.com/OpenFOAM/OpenFOAM...et/topoSetDict
   
   You can find it on your system by running:
   

   find $FOAM_UTILITIES  -name topoSetDict

   But keep in mind that if your internal mesh isn't already cut into the shape of the sphere, then all you get is a selection of the cells that are inside the sphere selection.

2. Originally Posted by wyldckat

   It's simple: setSet and topoSet are basically selection tools that can select parts of the mesh, including points, faces and cells. Once you select parts of the mesh and assign each selection a "tag" (i.e. a "set"), then you can do something with that "tag".

3. See also: http://www.cfd-online.com/Forums/ope...tml#post460374 - post #4

[nb977]

Hello ,
i need help regarding those 2 lines
what is the difference between add and new , and is it true that openFoam no longer use cellSet should i replace it with something else ?

cellSet refine new
cellSet refine add boxToCell (0.0 0.0 0.0) (0.584 0.146 0.584)
cellSet refine new boxToCell (0.0 0.146 0.0) (0.548 0.292 0.584)


Thank you

[wyldckat]

Quick answers:

Originally Posted by nb977

what is the difference between add and new

• "new" is for creating a new set.
• "add" is to add more items to the existing set.

Originally Posted by nb977

and is it true that openFoam no longer use cellSet should i replace it with something else ?

You're mixing up two things:

1. There was an application named "cellSet" in older versions of OpenFOAM.
2. The current setSet application has a command named "cellSet", which is still working. The lines you pointed out should work within setSet.

For more details: http://openfoamwiki.net/index.php/SetSet#Usage_example

[nb977]

Thank you very much i am now able to refine the region i wanted !

[Ben UWIHANGANYE]

Hello Foamers,

I want to ask if there is a way i can code a cylinderTocell field to oscillate.
Indeed, I created cylinderTocell field using topoSetDict, I want to know it can be put in motion.
I have seen in interFoam tutorials, setFieldsDict is used to give a linear velocity to a boxtocell Field. Is it posible to give it also an oscillating velocity?

Please help me to find out if there is a way this cylinderTocell Field can be moved(oscillating motion).

my ultimate goal is to simulate flow over that cylinder? (stationary and oscillating).
I thought that cylinder will be immersed not body fitted? Does it sound feasible?

I will be happy to hear from you.


Regards!