patchThick

Below is a demonstration of the features of the patchThick function

Syntax

[E,VE,Fq1,Fq2]=patchThick(F,V,dirSet,layerThickness,numSteps);

Description

Use patchThick to thicken a quadrilateral mesh to create hexahedral elements.

```clear; close all; clc;
```

Examples

PLOT SETTINGS

```fontSize=20;
```

Example: Using patchThick to thicken quads into hexahedra

Creating an example polygon

```ns=15;
t=linspace(0,pi,ns);
x=cos(t);
y=sin(t);
z=zeros(size(x));
Vc=flipud([x(:) y(:) z(:)]);
```

Extruding polygon to a quadrilateral surface

```cPar.depth=2;
cPar.dir=0;
cPar.closeLoopOpt=0;
cPar.numSteps=8;
[F,V]=polyExtrude(Vc,cPar);
```

Thickening quadrilaterial elements to hexahedral elements

```layerThickness=0.5;
numSteps=3;
[E,VE]=patchThick(F,V,1,layerThickness,numSteps);

%Use element2patch to get patch data
FE=element2patch(E);
```

Visualize mesh

```cFigure; hold on;
title('Hexahedral mesh');
gpatch(FE,VE,'bw','k',1);
axisGeom;
drawnow;
```

Example: Using patchThick to thicken triangles into pentahedra

Create test data set

```[F,V,C]=hemiSphereMesh(1,1,0);
V(:,3)=-V(:,3);
F=fliplr(F);
```

Thickening quadrilaterial surface to hexahedral elements

```layerThickness=0.4;
numSteps=2;
[E,VE,Fq1,Fq2]=patchThick(F,V,1,layerThickness,numSteps);

%Use element2patch to get patch data
FE=element2patch(E,[],'penta6');
```

Visualize mesh

```cFigure; hold on;
title('Pentahedral mesh');
gpatch(FE,VE,'bw','k',1);
% patchNormPlot(FE,VE);
axisGeom;
drawnow;
```

Example: Using patchThick to thicken a mixed mesh of quads and triangles

Create test data set

```[F,V,C]=hemiSphereMesh(1,1,0);
V(:,3)=-V(:,3);
F=fliplr(F);
```

Convert to mixed mesh

```optionStruct.maxAngleDeviation=90*(pi/180);
optionStruct.selectionMethod='best';
optionStruct.triangleConvert=0;
optionStruct.fourConnectConvert=0;
```

Thickening quadrilaterial surface to hexahedral elements

```layerThickness=0.4;
numSteps=2;
[E,VE,Fq1,Fq2]=patchThick(F,V,1,layerThickness,numSteps);

%Use element2patch to get patch data
FE=E;
for q=1:1:numel(E)
if size(E{q},2)==6
elementType='penta6';
elseif size(E{q},2)==8
elementType='hex8';
end
FE{q}=element2patch(E{q},[],elementType);
end
```

Visualize mesh

```cFigure; hold on;
title('Mixed hexahedral-pentahedral mesh');
for q=1:1:numel(FE)
gpatch(FE{q},VE,'bw','k',1);
end
% patchNormPlot(FE,VE);
axisGeom;
drawnow;
```

GIBBON www.gibboncode.org

Kevin Mattheus Moerman, [email protected]

GIBBON footer text

GIBBON: The Geometry and Image-based Bioengineering add-On. A toolbox for image segmentation, image-based modeling, meshing, and finite element analysis.

Copyright (C) 2019 Kevin Mattheus Moerman

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.