Any advice how to mesh this?

[Tekiti]

Hello All!
I have the following problem with meshing of a ragged solid. I always prefer meshing with brick elements but sometimes it is impossible to mesh a solid using bricks in the whole volume. I decided to divide this solid into three parts, where two of them can easily be meshed by bricks and the middle part has to be meshed by tetras. See the figure.


To connect these parts I don’t want to use weld contact. I would like mesh the middle part using the same nodes on the interfaces and then merge nodes. I have already tried to mesh yellow parts at border areas using “plot-only” quad elements, copy them to the same location, split them into triangles and then make associativity between these triangles and middle (red) solid. But Femap don’t take these elements into account during tetra meshing of middle part.
So my question is how to coerce Femap to mesh some solid using existing nodes on some face?? I hope, that some appropriate tool exists, because this can be done in Patran or in Abaqus.
Thank you very much,
M.

 

[Tekiti]

I am sorry.

http://postimg.org/image/6m92gbyq5/

 

[BlasMolero]

Hello!,
NX NASTRAN GLUE surface-to-surface do the job perfectly. Glue is a simple and effective method to join meshes which are dissimilar. It correctly transfers displacement and loads resulting in an accurate strain and stress condition at the interface. The grid points on glued edges and surfaces do not need to be coincident.

Glue creates stiff springs or a weld like connection to prevent relative motion in all directions. Surface-to-surface glue definitions are supported in all solution sequences except for SOL 144–146, and 701. In the heat transfer solutions 153 and 159, they are treated as conductivity connections. The "trick" is to use the same element size in both sides of GLUE contact, OK?.

Best regards,
Blas.

PD
In fact, NX NASTRAN uses the CPYRAM element to model pyramid element transitions between the tetrahedral mesh and an adjacent hexahedral mesh. Actually the CPYRAM element is supported in current version fo FEMAP V11.1.1. Yes, but mesh transition is not done automatically. According FEMAP developers an intent is done to support it in next major release of FEMAP at the end of this year.

~~~~~~~~~~~~~~~~~~~~~~
Blas Molero Hidalgo
Ingeniero Industrial
Director

IBERISA
48004 BILBAO (SPAIN)
WEB:

http://www.iberisa.com

Blog de FEMAP & NX Nastran:

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[Tekiti]

To tell the truth I am using Femap as a preprocessor and NEi Nastran as a solver. I have already tried to use weld contact, but in some cases it doesn´t work well. I think that to connect mesh it is possible to use hard points (Mesh - Mesh Control - Mesh points on surface). But the use in Femap is problematic.