SfePy April 2014

sfepy@python.org

3 participants
7 discussions

Re: Torque
by Robert Cimrman 09 Mar '18

09 Mar '18

In examples/large_deformation/hyperelastic.py a rotation by displacements is applied. By using a similar function the vectors defining the force couples could be defined for dw_surface_ltr (IMHO). Does it make sense? r. ----- Reply message ----- From: "Andre Smit" <freev...(a)gmail.com> To: <sfepy...(a)googlegroups.com> Subject: Torque Date: Sat, Dec 18, 2010 05:10 What is the best way to apply a torque load to a model? -- Andre -- You received this message because you are subscribed to the Google Groups "sfepy-devel" group. To post to this group, send email to sfepy...(a)googlegroups.com. To unsubscribe from this group, send email to sfepy-devel...(a)googlegroups.com. For more options, visit this group at http://groups.google.com/group/sfepy-devel?hl=en.

4 7

1D line elements in SfePy
by Nimish 22 Jan '16

22 Jan '16

I am currrently looking for FEM packages to help me solve a system of beams and columns, basically a collection of 1D bernoulli/timoshenko line elements. I started reading SfePy docs and i am getting the idea that doing the above is not really possible here, am i right? Are only 2D area elements permitted in SfePy? Or is there any direct support for solving 1D line elements too.. Cheers Nimish

4 9

Python 3 compatibility
by Robert Cimrman 11 Aug '14

11 Aug '14

FYI: As SciPy 0.12.0 is out and one of the release highlights is "Support for Python 2 and Python 3 from the same code base (no more 2to3)", we can think seriously about updating SfePy in this respect as well, cf. [1]. r. [1] https://github.com/sfepy/sfepy/issues/164

4 5

interactive solution analysis
by seismo_phil 08 Apr '14

08 Apr '14

Hi again, Further to my previous post on d_surface_flux, I thought I should be able to evaluate the surface heat flux myself, by solving the problem interactively and calculating the surface gradient myself. I use: pb, state = solve_pde('flndrs2d.py') t = state.get_parts()['t'] which returns temperatures. Now all I need are the corresponding coordinates. So I try: xy = pb.get_mesh_coors() But of course the coordinates vector is longer than the temperature one, I presume because the ebcs have resulted in removal of the corresponding DOFs. Is there anyway I can either (a) restore the full temperature vector, so I have temperatures at all the nodes, even the ones with ebcs applied, or (b) get the coordinates for only those nodes which do not have ebcs applied, i.e. coordinates that correspond to the temperatures returned by state.get_parts()? I tried pb.remove_bcs(), but was unsure if that affects anything other than the stiffness matrix. Again, any suggestions? Many thanks, - Phil

2 3

load.f dependent on region
by seismo_phil 08 Apr '14

08 Apr '14

Hi, I have another question relating to the thermal diffusion problem I am working on. There is a background heat production distributed throughout the volume, but the heat production for any given cell will depend on which region the cell is in, where region is determined by cell group. I.e., all cells of group 1 are defined to comprise region 1, and they have a heat production that is different from that in region 2. So far the examples I've seen have a load that depends only on coordinate. Is there any example in which the load depends on the region? Many thanks, - Phil

2 1

d_surface_flux problem
by seismo_phil 07 Apr '14

07 Apr '14

Hello, I'm still working on the same thermal diffusion problem I referred to in the "thermal diffusion - Dirichlet vs. Neumann BCs" thread. The problem is attached file "flndrs2d.py" and *appears* to give a reasonable solution, but I still need to calculate heat flux out the top of the model. So, following Robert's suggestion i added a post_process hook that evaluates d_surface_flux: def post_process(out, problem, state, extend=False): """ Calculate gradient of the solution. """ flux = problem.evaluate('d_surface_flux.2.Gamma_Top(coef.val, t)', mode='eval', copy_materials=False, verbose=False) print flux When I call this using my rather complicated materials definition in the attached file, d_surface flux fails with the following error: File "/Users/philcummins/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/sfepy/discrete/functions.py", line 114, in get_constants nqp = qps.shape[ig][1] KeyError: 1 (after a lengthy traceback). If I change the materials definition to a very simple one: materials = { 'flux' : ({'val' : 0.03},), 'coef' : ({'val' : 1.0},), } Then d_surface_flux appears to evaluate OK, but it just returns a single value of zero. (I am expecting a vector). I'm not sure what to try next, any suggestions? Many thanks - Phil P.S. I have also attached a coarsened mesh file, in case anyone wants to try to run it. But you need to remove the "2km" in the name of the mesh file in flndrs2d.py if you want it to work.

2 2

Evaluate a solution in the arbitrary point in the domain
by Alec Kalinin 03 Apr '14

03 Apr '14

Dear SfePy users, Is it possible to evaluate a solution not only in the FEM mesh node, but in any arbitrary point in the domain with the given (x, y, z) coordinates? For example, consider Dirichlet problem for Poisson equation. We apply essential boundary conditions on the surface nodes and after the problem has been solved we have the solution vector, i.e. vector of values in the FEM mesh nodes. But I want to know the solution in point v(x, y, z) that is not FEM mesh node. What is the best way to obtain solution in this point v? Sincerely, Alec Kalinin

3 25

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

SfePy April 2014