3D Mixed hex and tetra meshing

Altair Forum User

Dear sir/ Ma'am,

1) I have a 3D model for which I wish to do Hex meshing. I have divided my model in several parts and I could hex mesh some of them. But since I am       not able to hex mesh all of them I want to go with a mixed meshing i.e., tetra meshing for the remaining parts. May somebody please tell me the way       to achieve what I am wishing to do? [Please tell me the path to the suggested options in the hypermesh]

     I could have meshed my model completely with the 2nd order tetras but I want to have hex elements at the contacts.

2) Please, also tell me if there is any problem in using mixed (hex-pent- tetra) meshing in the transient (explicit) analysis. What type of elements (including for 2d meshing) are suggested for a transient structural analysis of a large assembly (also for the individual components) having loads applied for milliseconds? [It's not the case of crash analysis] 

Thank you in advance! /emoticons/default_smile.png' srcset='/emoticons/smile@2x.png 2x' title=':)' width='20' />

Altair Forum User

Hi,

Please go through the below post which is similar to your query.

 

Element selection is based on the type of problem you want to run, boundary conditions, geometry considerations, and results required. . Shells are excellent for thin 3D structures, such as body panels, sheet metal, injection molded plastic or any part that can be described as having a thickness that is small relative to its global dimensions. Solid elements are generally used for 3D structures not fitting into the shell description. Castings, forgings, block structures, and volumes are all good examples of 3D solid element structures.  Solid elements have the benefit of eliminating many assumptions found in the other element types but are generally more difficult to model.

Please download our free ebook on  Practical Aspects of Finite Element Simulation from http://www.altairuniversity.com/free-ebooks-2/free-ebook-practical-aspects-of-finite-element-simulation-a-study-guide/ which contains all the basics to meshing and analysis.

Altair Forum User

Altair Forum User said:

Hi,

Please go through the below post which is similar to your query.

 

Element selection is based on the type of problem you want to run, boundary conditions, geometry considerations, and results required. . Shells are excellent for thin 3D structures, such as body panels, sheet metal, injection molded plastic or any part that can be described as having a thickness that is small relative to its global dimensions. Solid elements are generally used for 3D structures not fitting into the shell description. Castings, forgings, block structures, and volumes are all good examples of 3D solid element structures.  Solid elements have the benefit of eliminating many assumptions found in the other element types but are generally more difficult to model.

Please download our free ebook on  Practical Aspects of Finite Element Simulation from http://www.altairuniversity.com/free-ebooks-2/free-ebook-practical-aspects-of-finite-element-simulation-a-study-guide/ which contains all the basics to meshing and analysis.

 

Altair Forum User

Thank you sir! I went through the answers of the query (by mirino) you suggested. It was helpful. But additionally, I want to know how to do tetra meshing for the remaining parts taking penta elements at the interfaces of hexa and tetra elements? Please also tell me the path to various pages and options in HyperMesh to get this mixed meshing done. [I have generated the hexa mesh for some of the parts].

Rahul Rajan_21763

You can refer below HyperWorks (Engineering solution) tutorials for Hybrid meshing.

CFD-1000: Creating a Hybrid Grid Using the CFD Mesh Panel

Altair Forum User

how to mix tetrahedral and brick mesh in single solid ?

Rahul Rajan_21763

Tetrahedral elements can be mixed to Hexahedral elements via pyramid elements. 4 triangular faces & one square face is for Pyramid elements.Above mentioned tutorial is example of Hybrid meshing.