Re: [Getfem-users] Centrifugal force

[Andriy Andreykiv]

Dear Simon,

I think one way to greatly speed up your program is to take into account the axi-symmetry of your problem.

Getfem fully supports it. That would mean that you can reduce your 2D problem to 1D.

You can create a simple line mesh, but using a type torus_mesh and subsequently create torus_mesh_fem on it.

Then you need to apply your force on a single edge/point of your mesh.

Best regards,

                        Andriy

On 1 February 2018 at 08:35, SIMON AMEYE <address@hidden> wrote:

Hi all,

 

I am asking for help again about my computation, that now works fine thanks to you, but slowly.

My 2D mesh represents a part that is spinning around a point (0,0).

To considerate the centrifugal force, I now calculate the area of each element, and apply a force using “source term brick” on its boundaries.

The problem is that add 2000 sources terms for 2000 elements is slow.

Do you have any idea of which brick I need to use to set the force in one step ?

The centrifugal force is described this way : “ F=constant*R “ where R is the distance between the rotation point and the element.

 

To get an idea about my actual code, here it is :

 

 

Setting all the regions by locating the faces

for i = 1:NumberOfElements

ftri_rand = get(rot_mesh,'faces from cvid',(i+1));

rot_mesh.set_region(i, ftri_rand);

end

 

Applying a force on each region

for i = 1: NumberOfElements

gf_model_set(md, 'add initialized data', ['VolumicData' num2str(i)], [Fx_tri(i), Fy_tri(i)]./Perimeter(i));

gf_model_set(md, 'add source term brick', mim, 'u', ['VolumicData' num2str(i)], i);

end

 

Thank you again for your help,

 

Simon Ameye

 

 

SIMON AMEYE DQI/DRIA/DSTF/SEPC Apprenti IFP School CENTRE TECHNIQUE VELIZY A /