what is the problem with this mesh?? its the primer mesh, except that it is the full section.
and is this right in selecting the top and bottom point (center is at 0,0) -
regions = { 'Omega' : ('all', {}), 'Bottom' : ('nodes in (x <= 0) & (y <= -75)', {}), 'Top' : ('nodes in (x <= 0) & (y <= 75)', {}), }
On 01/12/12 22:59, Md. Golam Rashed wrote:
what is the problem with this mesh?? its the primer mesh, except that it is the full section.
and is this right in selecting the top and bottom point (center is at 0,0) -
regions = { 'Omega' : ('all', {}), 'Bottom' : ('nodes in (x<= 0)& (y<= -75)', {}), 'Top' : ('nodes in (x<= 0)& (y<= 75)', {}), }
When I visualize the mesh, the connectivity and also some coordinates of vertices are wrong.
r.
I crated it with gmsh. however, i think what went wron is reformatting it in 2D by deleting edge blocks. what is described in the primer is not clear to me ( http://docs.sfepy.org/doc-devel/primer.html#meshing), i deleted the edge block and deleted the 4th column on Vertices. what went wrong then?
On 01/13/12 09:48, Md. Golam Rashed wrote:
I crated it with gmsh. however, i think what went wron is reformatting it in 2D by deleting edge blocks. what is described in the primer is not clear to me ( http://docs.sfepy.org/doc-devel/primer.html#meshing), i deleted the edge block and deleted the 4th column on Vertices. what went wrong then?
The 4th column of vertices was not deleted - after I deleted it (see attachment), it is ok.
The rule is: Dimension 3 - 4 columns, Dimension 2 - 3 columns - the last column is node id, could be used for defining regions.
r.
On 01/13/12 10:04, Md. Golam Rashed wrote:
so how can i define a region by the node id if i deleted the 4th column?
'nodes of group <integer>', see [1]. <integer> is the node group number - the last column. (Sorry, it's not id as it's not unique :)).
r. [1] http://docs.sfepy.org/doc-devel/users_guide.html#problem-description-file
its the same primer problem except that it has the full dia of 150 mm. vertical displacement at the bottom is set to zero and load is applied at the top. but sfepy gives errors. why?
On 01/13/12 10:16, Md. Golam Rashed wrote:
its the same primer problem except that it has the full dia of 150 mm. vertical displacement at the bottom is set to zero and load is applied at the top. but sfepy gives errors. why?
Fixing just one node is not enough to prevent rigid body motions, so the matrix is singular. Try fixing one node completely and a second node so that it prevents rotation around the first one.
r.
participants (2)
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Md. Golam Rashed
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Robert Cimrman