& Construction
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Integrated BIM tools, including Revit, AutoCAD, and Civil 3D
& Manufacturing
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Professional CAD/CAM tools built on Inventor and AutoCAD
Integrated BIM tools, including Revit, AutoCAD, and Civil 3D
Professional CAD/CAM tools built on Inventor and AutoCAD
Transcript
00:03
It is often necessary to edit a mesh using various objects to provide more detail
00:09
and improve the representation of the underlying topography.
00:14
These mesh editing objects can be manually added or taken from external files, layers displayed in the GeoPlan view,
00:22
or objects within the network.
00:25
Voids are polygon mesh objects that can be used for excluding areas from the 2D mesh.
00:32
A common historical use of voids was to represent buildings within the 2D area.
00:39
The advantage of using voids is that they reduce the overall number of mesh elements and therefore simulation time.
00:47
The disadvantage is that they represent an infinitely high impermeable barrier, which is unrealistic.
00:55
To add voids to a 2D mesh, you create polygons and associate them with a common category name.
01:03
In this example model, you can see that there are several polygons already created to represent buildings, shown in red.
01:12
Next, associate a common category, so that the mesh engine knows which polygons to use.
01:20
From the Windows toolbar, Grid windows drop-down, select New polygons window.
01:28
In the grid window, switch to the Polygon tab.
01:32
Click the Category column header to select the column, then right-click it and select Current cell(s) value > Set new value(s) for cell(s).
01:45
Enter a new value of Voids, and then click OK.
01:50
Close the window.
01:53
Now, re-mesh the 2D zone to include these changes in the mesh.
01:58
Select the 2D zone on the GeoPlan, and from the Model menu, select Meshing > Mesh 2D zones.
02:07
In the Mesh 2D Zones dialog, within the Voids area, make sure that you select Polygons and select the Void category.
02:22
Click OK to mesh the 2D zone.
02:25
In the Schedule Job(s) popup, click OK.
02:29
Once the mesh loads, you can see that the polygon areas have been excluded from the mesh generation,
02:37
as they have no internal 2D elements.
02:40
Therefore, the boundaries are treated as an infinitely high impermeable barrier by the 2D engine.
Video transcript
00:03
It is often necessary to edit a mesh using various objects to provide more detail
00:09
and improve the representation of the underlying topography.
00:14
These mesh editing objects can be manually added or taken from external files, layers displayed in the GeoPlan view,
00:22
or objects within the network.
00:25
Voids are polygon mesh objects that can be used for excluding areas from the 2D mesh.
00:32
A common historical use of voids was to represent buildings within the 2D area.
00:39
The advantage of using voids is that they reduce the overall number of mesh elements and therefore simulation time.
00:47
The disadvantage is that they represent an infinitely high impermeable barrier, which is unrealistic.
00:55
To add voids to a 2D mesh, you create polygons and associate them with a common category name.
01:03
In this example model, you can see that there are several polygons already created to represent buildings, shown in red.
01:12
Next, associate a common category, so that the mesh engine knows which polygons to use.
01:20
From the Windows toolbar, Grid windows drop-down, select New polygons window.
01:28
In the grid window, switch to the Polygon tab.
01:32
Click the Category column header to select the column, then right-click it and select Current cell(s) value > Set new value(s) for cell(s).
01:45
Enter a new value of Voids, and then click OK.
01:50
Close the window.
01:53
Now, re-mesh the 2D zone to include these changes in the mesh.
01:58
Select the 2D zone on the GeoPlan, and from the Model menu, select Meshing > Mesh 2D zones.
02:07
In the Mesh 2D Zones dialog, within the Voids area, make sure that you select Polygons and select the Void category.
02:22
Click OK to mesh the 2D zone.
02:25
In the Schedule Job(s) popup, click OK.
02:29
Once the mesh loads, you can see that the polygon areas have been excluded from the mesh generation,
02:37
as they have no internal 2D elements.
02:40
Therefore, the boundaries are treated as an infinitely high impermeable barrier by the 2D engine.
Voids are polygon mesh objects that can be used for excluding areas from the 2D mesh. A common use of voids is to represent buildings within the 2D area.
The advantage of using voids is that they reduce the overall number of mesh elements and therefore simulation time. The disadvantage is that they represent an infinitely high impermeable barrier, which is unrealistic.
To add voids to a 2D mesh, polygons are created and associated with a common category name. In this example model, there are several polygons already created to represent buildings.
To associate a common category, so that the mesh engine knows which polygons to use:
Now, re-mesh the 2D zone to include these changes in the mesh:
When the mesh loads, the polygon areas are excluded from the mesh generation, as they have no internal 2D elements. Therefore, the boundaries are treated as an infinitely high impermeable barrier by the 2D engine.
To view these excluded areas within the mesh, turn off the display of polygons:
Now, the areas excluded by the polygon voids are visible within the 2D mesh.
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