Dear Andriy, Thank you for your explanation.
Regarding creep, at the moment I only use liner_elasticity_brick with young’s modulus being changed on each time-step. This is just to start with. I am new in Getfem in fact. Could you please advise about the follows? 1. Are you using c++ to run getfem? If so, can you give some hints how I can to it? I can’t see any instruction about setting up for c++. 2. If you don’t use c++, how do you normally use the getfem::temporary_mesh_deformator (from getfem_deformable_mesh.h) or other C functions? I was trying to see if it is possible to use this function in Python interface by using SWIG or Python.Boost. But it is far beyond my knowledge. Thank you very much Regards Zhenghuai Guo From: Andriy Andreykiv <[email protected]> Sent: Wednesday, November 7, 2018 8:32 PM To: Zhenghuai Guo <[email protected]> Cc: [email protected] Subject: Re: [Getfem-users] mesh_deformation Dear Zhenghuai Guo, I don't use Python interface much, but your assumption is correct, using getfem::temporary_mesh_deformator (from getfem_deformable_mesh.h) you can apply displacement field to the mesh. By default temporary_mesh_deformator will deform the mesh and un-deform it in the destructor, unless you build it with the argument to_be_restored=false. I only assume that you can do it with Python too. I'm not really experienced with creep, but intuitively I would assume that you can also use large deformation formulation to account for the change in geometry. Or it's not how you intend it? In your follow up email you are asking about the usage of mesh slices. From what I know it's used primarily for post-processing, not calculation. If you intend to use it solely for post-processing than you can easily achieve it nowadays with Paraview, were you import a vtk file, warp the result with a displacement field and take a desired slice. Best regards, Andriy On Sat, 3 Nov 2018 at 12:33, Zhenghuai Guo <[email protected]<mailto:[email protected]>> wrote: Dear Sir or Madam, Could you please advise how I and deform a mesh according to a displacement field? I am trying to simulate a time dependent deformation of a cylinder like object using python-interface. After applying stress the object creeps with time. I think I can just go with many small time steps. In each time step, I would like to update and deform the mesh according to the displacement calculated as a function of time. And the deformed mesh will be an input for next time step. I can see there is some related information such as (1) ‘getfem_deformable_mesh.h’ in page 18 in https://download-mirror.savannah.gnu.org/releases/getfem/doc/getfem_project.pdf (2) ‘getfem::slicer_apply_deformation’ in http://getfem.org/userdoc/export.html#getfem::slicer_apply_deformation . But I can find details examples. Thank you very much Zhenghuai Guo Tyree Xray CT network facility, School of Minerals and Energy Engineering Resources, UNSW Sydney
