GiD forum

Hello All,

We bought 6.* version of GID, and use GID 6.3-beta version (This problems appears in GID 6.1.2 and GID 7.0.1). Sometimes, this version generates wrong mesh (see attached file new.msh, nodes # 46 and 55).
Those middle nodes of quadratic triangular elements are situated not on the middle of edges, where they should be (the same happens with quadratic quadrilateral elements). So we have some problem with it.



--
Best regards,
Oleg mailto:oleg2205 at mail.ru
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The midnodes of quadratic elements are not located on the middle of the
edges:
First are located on this position, but after, are remapped over the surface
source.
In your case, possibly the surface parametrización is not uniform, and the
projection of
the midnode over the surface is far of the wished position.

If the midpoint is far of the surface (big element size), can appear
instability
problems in the projection algorithm.

If you need the quadratic node exactly in the mid-edge (not necessary over
the surface if curved), then mesh with linear elements, or recompute the
midnode coordinates=(Node prev+Node next)/2 (inside the bas file, or inside
your own program)

Enrique Escolano

----- Original Message -----
From: "Oleg" oleg2205 at mail.ru
To: gidlist at gatxan.cimne.upc.es
Sent: Monday, August 12, 2002 7:12 PM
Subject: [GiDlist] Troubles with quadratic elemnt type mesh!!!!!!!!!!!



Hello All,

We bought 6.* version of GID, and use GID 6.3-beta version (This problems
appears in GID 6.1.2 and GID 7.0.1). Sometimes, this version generates wrong
mesh (see attached file new.msh, nodes # 46 and 55).
Those middle nodes of quadratic triangular elements are situated not on
the middle of edges, where they should be (the same happens with quadratic
quadrilateral elements). So we have some problem with it.



--
Best regards,
Oleg mailto:oleg2205 at mail.ru