-3D Meshing 3DMeshingaltairuniversity.com/wp-content/uploads/2014/02/3DMeshing.pdf · hexa elements.Pentas and hexas can be builtin anyofthe a vector to create solids. a line elements-3D

- 3D Meshing - 3D Meshing

3D Meshing3D Meshing3D Meshing

This chapter includes material from the book “Practical FinitThis chapter includes material from the book “Practical Finit

additional material added by Matthias Goelke.additional material added by Matthias Goelke.

When To Use 3D ElementsWhen To Use 3D ElementsWhen To Use 3D Elements

200Y

x ~ y ~ zX

x ~ y ~ z

100 ~ 200 ~ 50

X

100 ~ 200 ~ 50Z

3D elements should be used when all dimensions are comparable.3D elements should be used when all dimensions are comparable.

x ~ y ~ zx ~ y ~ z

Element shape – Tetra, penta, hex, pyramidElement shape – Tetra, penta, hex, pyramid

Additional data from user – NothingAdditional data from user – Nothing

Element type – SolidElement type – Solid

Practical applications: Gear box, engine block, crankshaft, etc.Practical applications: Gear box, engine block, crankshaft, etc.

Cylinder crankcase brick meshCylinder crankcase brick mesh

11

3D Meshing -3D Meshing -

Finite Element Analysis”. It also has been reviewed and has Finite Element Analysis”. It also has been reviewed and has

100100

2005050

parable.parable.

Crank Shaft Tetra MeshingCrank Shaft Tetra Meshing


3D Element Types3D Element Types3D Element Types

3D Elements3D Elements

Tetra Penta or WedgeTetra Penta or Wedge

Linear Penta 6Linear

Tetra 4Tetra 4

Parabolic Parabolic Penta 15Parabolic

Tetra 10

Parabolic Penta 15

Dofs For Solid ElementsDofs For Solid ElementsDofs For Solid Elements

2D thin shell and 1D beam element supports 6 dofs, but all solid2D thin shell and 1D beam element supports 6 dofs, but all solid

10 noded tetra element has total of 10 x 3 = 30 dofs10 noded tetra element has total of 10 x 3 = 30 dofs

Why does a solid element have only 3 translational and no rotationalWhy does a solid element have only 3 translational and no rotational

Consider a piece of paper (2D geometry) or long steel scale (1DConsider a piece of paper (2D geometry) or long steel scale (1D

But now consider a solid object like a duster or a paper weight. ItBut now consider a solid object like a duster or a paper weight. It

Hence, solid elements have been formulated with 3 translationalHence, solid elements have been formulated with 3 translational

Tetra Meshing TechniquesTetra Meshing Techniques

There are two methods of tetra meshing:There are two methods of tetra meshing:

1) Automatic mesh: This approach is limited to simple geometries1) Automatic mesh: This approach is limited to simple geometries

just has to select the volume and the software automatically carriesjust has to select the volume and the software automatically carries

criteria, etc.criteria, etc.

Advantage: Very quick, no meshing effortsAdvantage: Very quick, no meshing efforts

Disadvantage: Results in a very high number of nodes and elementsDisadvantage: Results in a very high number of nodes and elements

pattern requirement (like bolted, welded joints or contact surfacepattern requirement (like bolted, welded joints or contact surface

22


ElementsElements

Hex or Brick PyramidHex or Brick Pyramid

Linear Hex 8 Linear Pyram 5

Not supported byNot supported by

all softwareall software

Parabolic Hex 20 Parabolic Pyram 13Parabolic Hex 20 Parabolic Pyram 13

solid elements have only 3 translational dofs (no rotational dof) i.e. asolid elements have only 3 translational dofs (no rotational dof) i.e. a

tational dofs (physical interpretation)?tational dofs (physical interpretation)?

D geometry). It could be easily bent and twisted (rotational dof).D geometry). It could be easily bent and twisted (rotational dof).

It could not be subjected to very high bending or torsion stiffness.It could not be subjected to very high bending or torsion stiffness.

dofs and no rotational dofs.dofs and no rotational dofs.

tries and the pre-requisite is an error free CAD model. The usertries and the pre-requisite is an error free CAD model. The user

carries out the meshing as per the specified element length, qualitycarries out the meshing as per the specified element length, quality

ments. There is no control over the mesh flow and the specific meshments. There is no control over the mesh flow and the specific mesh

ace simulation).ace simulation).


2) 2D (tria) to 3D (tetra): This is the most commonly used method2) 2D (tria) to 3D (tetra): This is the most commonly used method

of the geometry. During the tetra meshing the quads are automaticallyof the geometry. During the tetra meshing the quads are automatically

elements.elements.

Steps for 2D (tria) to 3D (tetra) mesh generationSteps for 2D (tria) to 3D (tetra) mesh generation

Step 1) Study the geometryStep 1) Study the geometry

Step 2) Separate (isolate) the surfaces and split the job among engineerStep 2) Separate (isolate) the surfaces and split the job among engineer

a. CAE engineer 1a. CAE engineer 1

b. CAE engineer 2b. CAE engineer 2

33


thod. Quad or tria meshing is carried out on all the outer surfacesthod. Quad or tria meshing is carried out on all the outer surfaces

omatically split into trias which then serve as the “basis” of the tetraomatically split into trias which then serve as the “basis” of the tetra

engineers (if there is time constraint)engineers (if there is time constraint)


Step 3) Combine the meshStep 3) Combine the mesh

Step 4) Perform quality checks for the triangular elementsStep 4) Perform quality checks for the triangular elements

For instance, min. tria angle > 15 , Max. tria angle < 120For instance, min. tria angle > 150, Max. tria angle < 120

Step 5) Convert the tria mesh to a tetra meshStep 5) Convert the tria mesh to a tetra mesh

Step 6) Perform quality checks for the tetra elements (tet collapseStep 6) Perform quality checks for the tetra elements (tet collapse

the quality of the mesh if required.the quality of the mesh if required.

Step 7) Perform a free-free run or otherwise linear static analysis Step 7) Perform a free-free run or otherwise linear static analysis

Common Algorithms For Tria To Tetra ConversionCommon Algorithms For Tria To Tetra Conversion

• Advancing Front: This algorithm is very powerful and the most commonly used • Advancing Front: This algorithm is very powerful and the most commonly used

• Delaunay algorithm• Delaunay algorithm

• Tria-quad mesh• Tria-quad mesh

All algorithms provide the following two options for tria to tetra conAll algorithms provide the following two options for tria to tetra con

1)Floating trias: The original tria mesh generated by the user on1)Floating trias: The original tria mesh generated by the user on

tetra. Selection of this algorithm gives freedom to the software ttetra. Selection of this algorithm gives freedom to the software t

the tetra mesh generation). This option could be used for the meshingthe tetra mesh generation). This option could be used for the meshing

components representing stiffness or mass, etc.).components representing stiffness or mass, etc.).

2)Fixed trias: The original tria mesh and the generated tetra mesh2)Fixed trias: The original tria mesh and the generated tetra mesh

you intend to “glue”/merge individually meshed components togeyou intend to “glue”/merge individually meshed components toge

to not match resulting in an incompatibility of the mesh (i.e. the meshto not match resulting in an incompatibility of the mesh (i.e. the mesh

Original tria mesh Floating tria method:Original tria mesh Floating tria method:

Orientation of tria and tetra meshOrientation of tria and tetra mesh

is not the same (at cross patternis not the same (at cross pattern

of mesh)of mesh)

44


0 , jacobian > 0.6, zero free edges, no T-connection00, jacobian > 0.6, zero free edges, no T-connection

collapse > 0.1, Jacobian and distortion > 0.5, stretch > 0.2 etc.). Improvecollapse > 0.1, Jacobian and distortion > 0.5, stretch > 0.2 etc.). Improve

static analysis with dummy BC’s.static analysis with dummy BC’s.

most commonly used algorithm.most commonly used algorithm.

nversion:nversion:

on the outer surfaces might not match with the software producedon the outer surfaces might not match with the software produced

to change the triangular mesh pattern (in case of any problem into change the triangular mesh pattern (in case of any problem in

meshing of general components or areas (areas without high stress,meshing of general components or areas (areas without high stress,

mesh pattern match. This meshing option should be used whenevermesh pattern match. This meshing option should be used whenever

ether. Otherwise it may happen that the mesh of the componentsether. Otherwise it may happen that the mesh of the components

mesh would not be properly connected).mesh would not be properly connected).

Fixed tria method:Fixed tria method:

Orientation of tria and Orientation of tria and

tetrameshtetramesh

is the sameis the same


Brick MeshingBrick MeshingBrick Meshing

Brick meshing (also known as hex-meshing) is all about planning,Brick meshing (also known as hex-meshing) is all about planning,

and semi automatic meshing options. Automatic meshing or anand semi automatic meshing options. Automatic meshing or an

commercial software.commercial software.

Rear axle assembly with brake drum Rear axle assembly with brake drum

(Image source: Altair Calendar 2006,(Image source: Altair Calendar 2006,

The procedure for brick meshing of complicated parts is to first creaThe procedure for brick meshing of complicated parts is to first crea

elements by using the meshing commands extrude, spin, sweep,elements by using the meshing commands extrude, spin, sweep,

completion of hex meshing.completion of hex meshing.

Extrude / DragExtrude / Drag

55


planning, hard work and patience. Brick meshing supports only manualplanning, hard work and patience. Brick meshing supports only manual

an option like quad to brick (tria to tetra), is not supported byan option like quad to brick (tria to tetra), is not supported by

drum and wheel hub, brick meshdrum and wheel hub, brick mesh

Calendar 2006, Courtesy: Ashok Leyland)Calendar 2006, Courtesy: Ashok Leyland)

create a shell mesh on the surfaces and then convert this to hexcreate a shell mesh on the surfaces and then convert this to hex

eep, linear solid, etc. Free face check is very important after theeep, linear solid, etc. Free face check is very important after the


Rotate / SpinRotate / Spin

Sweep / Line DragSweep / Line Drag

Linear SolidLinear Solid

66



Tips For Brick MeshingTips For Brick MeshingTips For Brick Meshing

Even experienced engineers fear and do not willingly accept the jobEven experienced engineers fear and do not willingly accept the job

you how to brick mesh. The real teacher is a determined approachyou how to brick mesh. The real teacher is a determined approach

and learning from the mistakes.and learning from the mistakes.

1)Proper planning before starting the job: Sufficient time should1)Proper planning before starting the job: Sufficient time should

not be started until this is done. How to proceed next is visualizednot be started until this is done. How to proceed next is visualized

features are located, and if they exist, this could save you time.features are located, and if they exist, this could save you time.

2)2-D quad mesh should be systematic (ruled or mapped),2)2-D quad mesh should be systematic (ruled or mapped),

minimum number of trias and diamond or rotating quads shouldminimum number of trias and diamond or rotating quads should

results in a zig-zag or random mesh which might lead to unexpectresults in a zig-zag or random mesh which might lead to unexpect

3)Do not hurry to convert the shell mesh to brick: One should3)Do not hurry to convert the shell mesh to brick: One should

proceed further with the quads and checking for any possible problemproceed further with the quads and checking for any possible problem

4)Start from the most complicated feature and not the sim4)Start from the most complicated feature and not the sim

time management, the basic thumb rule told to students is to “Atime management, the basic thumb rule told to students is to “A

The thumb rule for brick meshing is exactly the reverse, i.e. “AttackThe thumb rule for brick meshing is exactly the reverse, i.e. “Attack

Beginners make a common mistake to mesh the simplest and outBeginners make a common mistake to mesh the simplest and out

5)Use the linear solid command: Linear solid and morphing5)Use the linear solid command: Linear solid and morphing

utilized.utilized.

Brick And Tetra Meshing ComparisonBrick And Tetra Meshing Comparison

vsvs

• The number of elements and nodes generated by a brick• The number of elements and nodes generated by a brick

mesh. A brick mesh reduces the solution time and resultsmesh. A brick mesh reduces the solution time and results

post display).post display).

• Analysis types like crash or nonlinear give preference • Analysis types like crash or nonlinear give preference

• The time consumed in brick meshing is more and requires • The time consumed in brick meshing is more and requires

• Over the years, the algorithm for tetra meshing has im• Over the years, the algorithm for tetra meshing has im

10 and brick 8 elements.10 and brick 8 elements.

How Not To MeshHow Not To MeshHow Not To Mesh

1) Mid nodes should lie exactly on the geometry1) Mid nodes should lie exactly on the geometry

Not acceptableNot acceptable

77


job of brick meshing. No book or consultant or university can teachjob of brick meshing. No book or consultant or university can teach

oach and hours of sitting in front of the computer, making mistakes,oach and hours of sitting in front of the computer, making mistakes,

should be spent in studying the geometry and meshing shouldshould be spent in studying the geometry and meshing should

visualized in the mesher’s mind. Symmetry, sub symmetry or repetitivevisualized in the mesher’s mind. Symmetry, sub symmetry or repetitive

ed), avoid 2-D auto mesh: Flow lines should be maintained withed), avoid 2-D auto mesh: Flow lines should be maintained with

should be avoided. Use of the auto mesher on surfaces sometimesshould be avoided. Use of the auto mesher on surfaces sometimes

ted problems later.ted problems later.

should not convert a 2D mesh to a 3D mesh immediately. Instead,should not convert a 2D mesh to a 3D mesh immediately. Instead,

roblem with the current pattern is recommended.roblem with the current pattern is recommended.

mplest one or a corner of the part: During exams for effectivemplest one or a corner of the part: During exams for effective

Attack the simple problems first and then the complicated one.”Attack the simple problems first and then the complicated one.”

ttack the complicated features first and then the simple ones”.ttack the complicated features first and then the simple ones”.

ter corners of the part first.ter corners of the part first.

phing are very powerful commands for brick meshing and should bephing are very powerful commands for brick meshing and should be

brick mesh are of the order of 1/2 to 1/50 in comparison to a tetrabrick mesh are of the order of 1/2 to 1/50 in comparison to a tetra

results in the ease of handling the model on a workstation (pre andresults in the ease of handling the model on a workstation (pre and

erence to brick mesh due to the number of nodes and mesh flow lines.erence to brick mesh due to the number of nodes and mesh flow lines.

uires experience, hard work, and a lot of patience too.uires experience, hard work, and a lot of patience too.

mproved and accuracy wise there is not much difference in tetramproved and accuracy wise there is not much difference in tetra

RecommendedRecommended


For a parabolic tetra meshing task, many CAE engineers preferFor a parabolic tetra meshing task, many CAE engineers prefer

covert it to parabolic. In the conversion process, mid nodes mightcovert it to parabolic. In the conversion process, mid nodes might

fillets. If so, it should be projected on corresponding surfaces beforefillets. If so, it should be projected on corresponding surfaces before

2) When the job is split among several engineers, the element2) When the job is split among several engineers, the element

The above job was split among 3 engineers due to a very shortThe above job was split among 3 engineers due to a very short

pattern was not followed by the engineers working independentlypattern was not followed by the engineers working independently

3) Minimum 2 elements on the fillets for tetra3) Minimum 2 elements on the fillets for tetra

meshingmeshing

Elements at fillets and curved surfaces usually fail in the jacobian/disElements at fillets and curved surfaces usually fail in the jacobian/dis

the element quality results in mesh deviation from the geometrythe element quality results in mesh deviation from the geometry

with 2 or more elements.with 2 or more elements.

88


to start with linear tria (instead of parabolic) meshing and thento start with linear tria (instead of parabolic) meshing and then

might not get projected automatically on the curved surfaces andmight not get projected automatically on the curved surfaces and

ore conversion to tetras.ore conversion to tetras.

ment length and over all mesh pattern should be consistent.ment length and over all mesh pattern should be consistent.

t time duration provided by the client. The same mesh size andt time duration provided by the client. The same mesh size and

on sub parts of the geometry.on sub parts of the geometry.

jacobian/distortion element check. The manual adjustment for improvingjacobian/distortion element check. The manual adjustment for improving

y and visible kinks. This could be avoided by modeling the filletsy and visible kinks. This could be avoided by modeling the fillets


4) For brick meshing, a minimum of 2 elements across the4) For brick meshing, a minimum of 2 elements across the

A single element leads to a poor interpolation and thus affects theA single element leads to a poor interpolation and thus affects the

thickness is recommended. The exception is NVH applications, wherethickness is recommended. The exception is NVH applications, where

mass and stiffness (with the least dofs) is the main criteria.mass and stiffness (with the least dofs) is the main criteria.

5) Use of tetra / pyramid elements while brick meshing5) Use of tetra / pyramid elements while brick meshing

PyramidPyramid

Some clients allow for a few tetra elements during brick meshing. AlsoSome clients allow for a few tetra elements during brick meshing. Also

Use of tetra and pyramid elements can make the life of a brick mesherUse of tetra and pyramid elements can make the life of a brick mesher

the use of these elements from the client.the use of these elements from the client.

6) Modeling a sheet metal part with 3D elements6) Modeling a sheet metal part with 3D elements

For sheet metal or very small thickness parts, 2D shell elements areFor sheet metal or very small thickness parts, 2D shell elements are

3D mesh, but it will result in a very high number of nodes and elements3D mesh, but it will result in a very high number of nodes and elements

Consider the following sheet metal part (200 x 200 x 2 mm). We willConsider the following sheet metal part (200 x 200 x 2 mm). We will

quad-4 (linear) elements using the same element length and comquad-4 (linear) elements using the same element length and com

3D Tetramesh3D Tetramesh

Nodes =1496 Elements = 689Nodes =1496 Elements = 689

99


thickness should be usedthickness should be used

the accuracy of the results. A minimum of 2 elements across anythe accuracy of the results. A minimum of 2 elements across any

where stress is not the main criteria, but the representation of thewhere stress is not the main criteria, but the representation of the

TetraTetra

Also some software and analysis types support pyramid elements.Also some software and analysis types support pyramid elements.

mesher tolerable. It’s good practice to clarify the instructions formesher tolerable. It’s good practice to clarify the instructions for

are better suited and recommended. It’s not like we cannot use aare better suited and recommended. It’s not like we cannot use a

elements.elements.

will mesh the same part with 3D parabolic tetra elements and 2Dwill mesh the same part with 3D parabolic tetra elements and 2D

mpare the number of nodes and elements needed.mpare the number of nodes and elements needed.

2D quad-4 mesh2D quad-4 mesh

Nodes = 121 Elements = 100Nodes = 121 Elements = 100


7) Limitation of 1D element and advantage of 3D meshing7) Limitation of 1D element and advantage of 3D meshing

Fillets, cutouts and complicated geometry features cannot be represenFillets, cutouts and complicated geometry features cannot be represen

3D elements, because of 3 dimensions, can capture all the minu3D elements, because of 3 dimensions, can capture all the minu

It is very difficult to capture the key way slot and variable fillet usingIt is very difficult to capture the key way slot and variable fillet using

applications.applications.

Creating 3D Elements Using HyperMeshCreating 3D Elements Using HyperMeshCreating 3D Elements Using HyperMesh

HyperMesh can be used to generate a tetra mesh or a brick mesh.HyperMesh can be used to generate a tetra mesh or a brick mesh.

meshing.meshing.

Tetra ElementsTetra Elements

Tetrahedral (tetra) elements are solid elements which have been Tetrahedral (tetra) elements are solid elements which have been

as shown below:as shown below:

HyperMesh builds 4- and 10-noded tetras. Tetra elements canHyperMesh builds 4- and 10-noded tetras. Tetra elements can

Tetramesh Process Manager template, and shrink wrap panel.Tetramesh Process Manager template, and shrink wrap panel.

1010


represented accurately by 1D elements.represented accurately by 1D elements.

minute details accurately. For example, consider the following shaft.minute details accurately. For example, consider the following shaft.

using 1D elements. Instead 3D meshing is recommended for suchusing 1D elements. Instead 3D meshing is recommended for such

mesh. Below is an explanation on how to perform both types ofmesh. Below is an explanation on how to perform both types of

e been extracted from 2D tria elements. They have a tetrahedral shapee been extracted from 2D tria elements. They have a tetrahedral shape

be created through the edit element panel, tetra mesh panel,be created through the edit element panel, tetra mesh panel,

1010


Edit Element PanelEdit Element Panel

Tetra elements can be created manually by using the edit elementTetra elements can be created manually by using the edit element

combine, split, or modify elements. Tetra elements can only be creacombine, split, or modify elements. Tetra elements can only be crea

Tetramesh PanelTetramesh Panel

Tetra elements can be automatically created using the tetrameshTetra elements can be automatically created using the tetramesh

with first or second order tetrahedral elements. A region is consideredwith first or second order tetrahedral elements. A region is considered

or quad elements).or quad elements).

Different sub-panels exist for different types of tetra meshing:Different sub-panels exist for different types of tetra meshing:

• tetra mesh: allows you to fill an arbitrary volume, defined• tetra mesh: allows you to fill an arbitrary volume, defined

elementselements

• tetra remesh: regenerates the mesh for a single volume • tetra remesh: regenerates the mesh for a single volume

• CFD mesh: allows you to automatically generate meshes• CFD mesh: allows you to automatically generate meshes

selected boundary regions/elements, and fill the remaining selected boundary regions/elements, and fill the remaining

• volume tetra: given a solid entity or a set of surfaces• volume tetra: given a solid entity or a set of surfaces

shell mesh and fills the enclosed volume with solid elementsshell mesh and fills the enclosed volume with solid elements

Shrink Wrap PanelShrink Wrap Panel

Within the shrink wrap panel there is an option to generate solidWithin the shrink wrap panel there is an option to generate solid

the selected elements or geometry. The shrink wrap can thus bethe selected elements or geometry. The shrink wrap can thus be

that when generating such a mesh, the Jacobian value has a largethat when generating such a mesh, the Jacobian value has a large

additional information, please refer to the online help.additional information, please refer to the online help.

Hexa And Penta ElementsHexa And Penta Elements

Hexahedral (hexa or brick) elements are solid elements which haHexahedral (hexa or brick) elements are solid elements which ha

elements are solid elements which have been extracted from 2D triaelements are solid elements which have been extracted from 2D tria

Hexa PentaHexa Penta

HyperMesh builds 6- and 15-noded pentas and 8- and 20-nodedHyperMesh builds 6- and 15-noded pentas and 8- and 20-noded

following panels:following panels:

• drag: Drags a group of two-dimensional elements along • drag: Drags a group of two-dimensional elements along

• edit element: builds elements by hand• edit element: builds elements by hand

• line drag: Drags a group of two-dimensional elements along • line drag: Drags a group of two-dimensional elements along

• linear solid: creates solid elements between two-dimensional • linear solid: creates solid elements between two-dimensional

1111


element panel. The “Edit Element” panel allows you to hand build, element panel. The “Edit Element” panel allows you to hand build,

be created in the edit element panel through the create subpanel.be created in the edit element panel through the create subpanel.

panel. The Tetramesh panel allows you to fill an enclosed volumepanel. The Tetramesh panel allows you to fill an enclosed volume

sidered enclosed if it is entirely bounded by a shell mesh (tria and/sidered enclosed if it is entirely bounded by a shell mesh (tria and/

defined by its surface using tria/quad elements, with tetrahedraldefined by its surface using tria/quad elements, with tetrahedral

olume of tetrahedral elementsolume of tetrahedral elements

meshes with boundary layer type elements (pyramids and hexas) frommeshes with boundary layer type elements (pyramids and hexas) from

remaining core volume with tetrahedral elementsremaining core volume with tetrahedral elements

representing a closed volume, this meshing option generates arepresenting a closed volume, this meshing option generates a

elementselements

solid mesh – this will produce an all-hexa or all-tetra mesh based onsolid mesh – this will produce an all-hexa or all-tetra mesh based on

be used as a quick mechanism to generate solid meshes. Notebe used as a quick mechanism to generate solid meshes. Note

large effect on the coarseness of the resulting volume mesh. Forlarge effect on the coarseness of the resulting volume mesh. For

ave been extracted from 2D quad elements. Pentahedral (penta)ave been extracted from 2D quad elements. Pentahedral (penta)

tria elements. Their shapes are shown below:tria elements. Their shapes are shown below:

oded hexa elements. Pentas and hexas can be built in any of theoded hexa elements. Pentas and hexas can be built in any of the

elements along a vector to create solids.elements along a vector to create solids.

elements along a lineelements along a line

dimensional elementsdimensional elements

1111


• solid map: builds solid elements between nodes, lines and su• solid map: builds solid elements between nodes, lines and su

• solid mesh: builds solid elements between a variable number • solid mesh: builds solid elements between a variable number

• elem offset: creates solid elements by offsetting a group• elem offset: creates solid elements by offsetting a group

the group of two-dimensional elementsthe group of two-dimensional elements

• spin: spins a group of two-dimensional elements about • spin: spins a group of two-dimensional elements about

• split: propagates split hexas• split: propagates split hexas

As stated above, pentas and hexas can be created in the solid mapAs stated above, pentas and hexas can be created in the solid map

Solid Map MeshingSolid Map Meshing

In the Solid Map panel, solid elements are created. These solidIn the Solid Map panel, solid elements are created. These solid

nodes, lines, and surfaces. Below is a short description on mappabilitnodes, lines, and surfaces. Below is a short description on mappabilit

for solid meshing, please refer to the online help topic Partitioningfor solid meshing, please refer to the online help topic Partitioning

In solid meshing, the ability to be meshed is referred to as mappabilitIn solid meshing, the ability to be meshed is referred to as mappabilit

a surface mesh on one face of the solid, then extending that mesha surface mesh on one face of the solid, then extending that mesh

perfect cylinder is mappable in one direction (the axis between itsperfect cylinder is mappable in one direction (the axis between its

(the axes between each pair of its identical faces). However, a combustion(the axes between each pair of its identical faces). However, a combustion

different radius joined together into a single solid entity would need

each cylinder would become mappable in one direction. Below iseach cylinder would become mappable in one direction. Below is

direction:direction:

While this example shows two faces that are of the same shapeWhile this example shows two faces that are of the same shape

source and destination can be of drastically different shape and consource and destination can be of drastically different shape and con

Any given volume can have one of four states, which are color-codedAny given volume can have one of four states, which are color-coded

toolbar. Although the colors can be customized, the default settings toolbar. Although the colors can be customized, the default settings

• Blue indicates a solid that has not been edited at all and there• Blue indicates a solid that has not been edited at all and there

• Orange indicates a solid that has been edited, but remains• Orange indicates a solid that has been edited, but remains

mapping).mapping).

• Yellow indicates a solid that is mappable in 1 direction.• Yellow indicates a solid that is mappable in 1 direction.

• Green indicates a solid that is mappable in three directions (this• Green indicates a solid that is mappable in three directions (this

1212


een nodes, lines and surfaceseen nodes, lines and surfaces

variable number of linesvariable number of lines

oup of two-dimensional elements normal to the surface formed byoup of two-dimensional elements normal to the surface formed by

about a vector to create solid elementsabout a vector to create solid elements

map panel. Below is a detailed description of this panel.map panel. Below is a detailed description of this panel.

solid elements can be created from solid geometry as well as fromsolid elements can be created from solid geometry as well as from

mappability. For a detailed explanation on how to split a solid geometrymappability. For a detailed explanation on how to split a solid geometry

titioning Solids for Mappability.titioning Solids for Mappability.

mappability. Mappability is directional and can be likened to puttingmappability. Mappability is directional and can be likened to putting

mesh along a vector through the solid volume. So, for example, amesh along a vector through the solid volume. So, for example, a

its top and bottom faces) while a perfect cube is mappable in threeits top and bottom faces) while a perfect cube is mappable in three

combustion engine’s cylinder head consisting of two cylinders ofcombustion engine’s cylinder head consisting of two cylinders of

need to be partitioned to divide the two cylinders. Once partitioned,

is an example which shows a volume which is mappable in oneis an example which shows a volume which is mappable in one

and directly oppose each other, that is not a requirement. The and directly oppose each other, that is not a requirement. The

contour and need not lie directly opposite each other.contour and need not lie directly opposite each other.

coded when using the mappable view option on the visualizationcoded when using the mappable view option on the visualization

ttings are:ttings are:

and therefore isn’t evaluated for mappability.and therefore isn’t evaluated for mappability.

remains completely unmappable (further partitioning may enableremains completely unmappable (further partitioning may enable

direction.direction.

three directions (this is very rare).three directions (this is very rare).

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In the images above, the first cube is mappable in 3 directions. TheIn the images above, the first cube is mappable in 3 directions. The

mappable in only 1 direction and the corner is not mappable withoutmappable in only 1 direction and the corner is not mappable without

The “Solid Map” panel for is used for solid-map meshing, and thisThe “Solid Map” panel for is used for solid-map meshing, and this

solid, and ends only sub-panels all draw from the same set of isolid, and ends only sub-panels all draw from the same set of i

controls that do not apply to their mapping techniques). Note thatcontrols that do not apply to their mapping techniques). Note that

then extrapolated into a 3D mesh based on the parameters you ithen extrapolated into a 3D mesh based on the parameters you i

automatically create 3D mesh directly on solids as long as the solidsautomatically create 3D mesh directly on solids as long as the solids

Solid Map PanelSolid Map Panel

• general: Use the general sub-panel to access all of the • general: Use the general sub-panel to access all of the

• line drag: Use the line drag sub-panel to select a 2D mesh,

the mapping direction.the mapping direction.

• linear solid: Use the linear solid sub-panel to select tw• linear solid: Use the linear solid sub-panel to select tw

them.them.

• ends only: Use the ends only sub-panel to select two opposing• ends only: Use the ends only sub-panel to select two opposing

between the surfaces.between the surfaces.

• one volume: Use the one volume sub-panel to select a• one volume: Use the one volume sub-panel to select a

• multi solids: Use the multi solids sub-panel to select multiple mappable • multi solids: Use the multi solids sub-panel to select multiple mappable

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The second image shows that if a corner is split off, it becomesThe second image shows that if a corner is split off, it becomes

without further partitioning.without further partitioning.

this panel includes several sub-panels. The general, line drag, linearthis panel includes several sub-panels. The general, line drag, linear

input controls (the more specialized panels simply filter out theinput controls (the more specialized panels simply filter out the

that all of these sub-panels depend on an existing 2D mesh, which isthat all of these sub-panels depend on an existing 2D mesh, which is

input. The one volume and multi solids sub-panels, however, caninput. The one volume and multi solids sub-panels, however, can

solids you select are already mappable.solids you select are already mappable.

the possible entry controls for maximum flexibility.the possible entry controls for maximum flexibility.

mesh, and then select a line from the model geometry to use as

wo existing 2D meshes and extrapolate a 3D mesh that connects wo existing 2D meshes and extrapolate a 3D mesh that connects

opposing surfaces and one 2D mesh, then extrapolate the meshopposing surfaces and one 2D mesh, then extrapolate the mesh

a single mappable solid volume and create a new 3D mesh for it.a single mappable solid volume and create a new 3D mesh for it.

multiple mappable solids and create 3D meshes for them.multiple mappable solids and create 3D meshes for them.

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9. Tutorials And Videos9. Tutorials And Videos9. Tutorials And Videos

Recommended TutorialsRecommended Tutorials

The tutorials listed below are included in the HyperWorks installation.The tutorials listed below are included in the HyperWorks installation.

• HM-3200: Tetrameshing• HM-3200: Tetrameshing

• HM-3210: Creating a Hex-Penta Mesh using Surfaces• HM-3210: Creating a Hex-Penta Mesh using Surfaces

• HM-3220: Creating a Hexahedral Mesh using the Solid Map • HM-3220: Creating a Hexahedral Mesh using the Solid Map

Additional tutorials about tetrahedral and hexahedral meshing are also Additional tutorials about tetrahedral and hexahedral meshing are also

category Tetrameshing we posted tutorials about tetrameshing of

editing of tetras.editing of tetras.

With respect to hexameshing you will be challenged to hexameshWith respect to hexameshing you will be challenged to hexamesh

it takes compared to tetrameshing the same part), and variousit takes compared to tetrameshing the same part), and various

provided by our team from India.provided by our team from India.

Recommended VideosRecommended Videos

Symmetrical mesh editSymmetrical mesh edit

(http://altair-2.wistia.com/medias/6r7jc6k231)(http://altair-2.wistia.com/medias/6r7jc6k231)

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orks installation.orks installation.

xahedral Mesh using the Solid Map Functionxahedral Mesh using the Solid Map Function

are also included in the Academic Training Center. In theare also included in the Academic Training Center. In the

trameshing of a steering wheel; working with tetra-elements, and local fixing/

a steering wheel (gives you also an idea about the additional timea steering wheel (gives you also an idea about the additional time

meshing projects ranging from simple to moderate complicatedmeshing projects ranging from simple to moderate complicated

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Symmetrical meshingSymmetrical meshing

(http://altair-2.wistia.com/medias/dbzc76mguv)(http://altair-2.wistia.com/medias/dbzc76mguv)

Gear solidmeshGear solidmesh

(http://altair-2.wistia.com/medias/u2lmb0ixfu)(http://altair-2.wistia.com/medias/u2lmb0ixfu)

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Gear shellmeshGear shellmesh

(http://altair-2.wistia.com/medias/r81811rb7u)(http://altair-2.wistia.com/medias/r81811rb7u)

Transition shellTransition shell

(http://altair-2.wistia.com/medias/ideze69n5m)(http://altair-2.wistia.com/medias/ideze69n5m)

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Transition solidTransition solid

(http://altair-2.wistia.com/medias/jkm1ht915e)(http://altair-2.wistia.com/medias/jkm1ht915e)

Hexa transitionHexa transition

(http://altair-2.wistia.com/medias/vaclbgnmen)(http://altair-2.wistia.com/medias/vaclbgnmen)

1717


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To view the Self Paced Training class aboutTo view the Self Paced Training class about

Hex Meshing using HyperMesh (http://www.altairhyperworks.com/training/self_paced/hHex Meshing using HyperMesh (http://www.altairhyperworks.com/training/self_paced/h

you need to login in the Client Center first (requires a eMail address you need to login in the Client Center first (requires a eMail address

Tetrameshing (http://altair-2.wistia.com/medias/fk0y05vnm5)Tetrameshing (http://altair-2.wistia.com/medias/fk0y05vnm5)

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orks.com/training/self_paced/hex_mesh/index.aspx)orks.com/training/self_paced/hex_mesh/index.aspx)

eMail address of your campus)eMail address of your campus)

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Tips and Tricks for Tetrameshing with HyperMeshTips and Tricks for Tetrameshing with HyperMesh

(http://www.altairhyperworks.de/ResLibSearchResult.aspx?file_id=(http://www.altairhyperworks.de/ResLibSearchResult.aspx?file_id=

service=All&category=All&order_by=date_created&order_by_da=desc#26service=All&category=All&order_by=date_created&order_by_da=desc#26

Note:Note:

More videos are continuously uploaded to the Academic Training CenMore videos are continuously uploaded to the Academic Training Cen

1919


esult.aspx?file_id=1493&keywords=mesh&industry=All&product_esult.aspx?file_id=1493&keywords=mesh&industry=All&product_

y_da=desc#2607)y_da=desc#2607)

Center: Modeling >Meshing >3D >Videos(3D)Center: Modeling >Meshing >3D >Videos(3D)

1919

Documents

-3D Meshing 3DMeshingaltairuniversity.com/wp-content/uploads/2014/02/3DMeshing.pdf · hexa elements.Pentas and hexas can be builtin anyofthe a vector to create solids. a line elements-3D