Sweep method generates sweep mesh on "sweepable" bodies (including axis-sweepable bodies, which are not displayed when you use the Show Sweepable Bodies feature). The mesher fails, when a swept mesh cannot be generated on a body with a Sweep Method control.
Use the Sweep option when you require:
a swept mesh.
a swept mesh on a model that revolves around an axis where the source and target faces share topology.
To access the Sweep Method,
On the Tree Outline, right-click Mesh and click Insert > Method.
Or
On the Tree Outline, click Mesh and click Method in the Mesh Context tab on the Ribbon, then click Method. Set Method as Sweep in Automatic Method Details view.
Sweep Method Details view has the following options:
Scope
Scoping Method: Allows you to scope geometry or named selection. The available options are Geometry Selection and Named Selection. The default value is Geometry Selection.
Geometry Selection: Allow you to scope the geometry bodies.
Named Selection: Allow you to scope the bodies grouped under a named selection.
Definition
Suppressed: Allows you to suppress the method control. The default value is No. When Suppressed is set to Yes, the Active is available. Active is a read-only and provides the number of suppressed parts
Method: Allows you to select the method control.
When you select the Sweep option, the Details View expands to include additional settings, many of which are unique to this option. For basic usage that involves obtaining a swept mesh, the procedure is to apply a Method Control to one or more bodies, set Method to Sweep, and accept the default values of the various settings.
For advanced or specialized usage such as meshing thin models or axis sweeping, adjust the settings as needed. The following is a description of each of these settings.
Algorithm: Allows you to select algorithm. The available options are Program Controlled and Axisymmetric. The default is Program Controlled .
: Applies to only on the traditional sweepable bodies which can be detected by Show Sweepable Bodies.
: Applies to all axisymmetric models. Axisymmetric Sweeper does not support shared topology. Axisymmetric Sweeper supports Contact Sizing and Topology Protection.
Mesh In Center: Defines the type of mesh in the centre of the Axisymmetric model. Mesh in Center is available only when Algorithm is Axisymmetric. The default value is Hexahedra. The available options are:
Wedges: Generates wedges at the center of the axisymmetric model.
Hexahedra: Generates O-Grid mesh at the centre of the axisymmetric model. You can specify the number of divisions for the O-Grid using the O-Grid Divisions.
Element Order: Allows you to select element order for mesh. Refer to Method Controls and Element Order Settings.
O-Grid Divisions: Define the number of divisions per quadrant from the center of the O-Grid to the boundary (or outside) of the O-Grid. The default value for O-Grid Divisions is 4. O-Grid Divisions is available only when you select Axisymmetric algorithm.
Project Corners to Top: Projects the nodes on the steps along the body of interest to the top surface of the Axisymmetric model. The default value is Yes. Project Corners to Top is available only when Algorithm is Axisymmetric .
Src/Trg Selection: Defines the source and target selection type according to the following choices:
: Determines automatically the best source and target for the body.
: Allows you to select the source and the program determines the target. is useful when there are multiple source target pairs, and you want to specify the source to get the correct bias through the sweep direction. Another application is when your cross section is changing, and the mesh quality would be better when sweeping from one side vs. another.
: Allows you to select the source and target manually. The sweeper revolves the mesh around common edges or vertices. You can use Manual Source and Target when you want to sweep a body where the source and target faces share vertices or edges or both.
: Allows you to select thin models and thin sheet metal parts and sweep a mesh through the thickness of the body. For Automatic Thin, the face with the largest face area is selected as the primary source and the algorithm determines the rest of the source faces. For multibody parts, only one division through the thickness is possible. For single body parts, you can define multiple elements through the thickness using the Sweep Num Divs control. Biasing is not available. User Defined Criteria allows you to select the type of Automatic Thin sweep. This option is available only when the Src/Trg Selection is set to Automatic Thin. The available options are Program Controlled and Protect Internal Edges. When you select Program Controlled, the interior loops in the model are not preserved while performing thin sweep. When you select Protect Internal Edges, the interior loops in the model are preserved while performing thin sweep. An Element Option setting is included that instructs the solver to use the Solid Shell element where possible, or to always use a Solid element.
: The same restrictions apply as described above for . However, with this choice, you can do any of the following:
Pick one source face and allow the program to determine the rest.
Pick all the source faces and allow the program to do nothing but mesh the source faces and sweep them to the target.
Pick multiple source faces and mesh one target face.
Note:The Sweep mesh method does not support the , , or settings for Src/Trg Selection if Sweep is applied to more than one part, even if you suppress all of the other parts.
In some cases, the thin model sweeper may want to swap source and target faces based on meshing conditions in neighboring bodies. In such cases, you receive a warning message.
Refer to Considerations for Selecting Source Faces for the Thin Model Sweeper for details.
To make source/target face selection easier, select from the Toolbar and then deselect Body Scoping Annotations in the Annotation Preferences option box to toggle the visibility of annotations in the Geometry window. For example, after scoping Sweep to a body, the body will be displayed using a blue solid annotation. Turn off the body scoping annotations, then select the source/target faces. For picking internal faces, the Hide Faces right-click option may help you to see inside a body. For example, you can select external faces in the Geometry window and then use the Hide Faces option to hide the selected faces (making it easier to select the internal faces).
Source Scoping Method: Defines the method for choosing a source face or target face. Source Scoping Method is Program Controlled and read-only when you select Src/Trg Selection as Automatic or Automatic Thin. The available options are Geometry Selection and Named Selection.
Geometry Selection: Enables you to select sources or targets manually using the Source option.
Named Selection: Enables you to choose one Named Selection as a source or target using the Source Named Selection option.
Target Scoping Method: Defines the method for scoping targets when Src/Trg Selection is Manual Source and Target. The available options are Geometry Selection and Named Selection.
Geometry Selection: Allows you to select the target from the Geometry window using Target option .
Named Selection: Allows you to select the target from the available named selections using Target Named Selection option.
Free Face Mesh Type: Determines the shape of the elements used to fill the swept body (pure hex, pure wedge, or a combination of hex/wedge). The default value is . The available options are :
: Fills the swept body with triangular elements.
: Fills the swept body with quadrilateral or triangular elements.
: Fills the Swept body with quadrilateral elements.
When Src/Trg Selection is , , or ,Free Face Mesh Type allows you to choose , , or meshing
When Src/Trg Selection is or , Free Face Mesh Type allows you to choose or meshing .
Note:If the source face is also a side face of another body, the face is always quad mapped.
When Free Face Mesh Type is set to either or and the source face can be mapped meshed, the face is sometimes mapped meshed ignoring the applied sizing controls (such as Contact Sizing, ,and more).
In some cases, when Src/Trg Selection is set to Automatic, automatically selected source face should be quad mapped to get a successful sweep mesh. In such cases, the value specified for Free Face Mesh Type may be ignored.
Type: Allows you to specify whether to use or through the sweep direction. The available options are:
Element Size: Specifies the size of elements to be created in the sweep direction.
Sweep Element Size: Provides the size of elements created in the sweep direction.
Number of Division: Specifies the number of elements to be created in the sweep direction.
Sweep Num Divs: Provides the number of elements to be created in the sweep direction.
When sweeping generalized bodies that share faces, the is a soft constraint on interval assignment and the is a hard constraint. If you have conflicting constraints, the sweeper will fail and yield a message. To obtain a regular mesh in the sweep direction, the guiding edges must have consistent lengths. You can define virtual split edges to achieve consistent lengths for these edges (see Creating and Managing Virtual Split Edges). Also see Sizing Control for more information.
Note: The Type Element Size is not available for Axisymmetric algorithm.
User Defined Criteria: Allows you to select the type of Automatic Thin sweep. User Defined Criteria is available only when the Src/Trg Selection is Automatic Thin. The default option is Program Controlled. The available options are Program Controlled and Protect Internal Edges.
Program Controlled: Performs thin sweep without preserving the interior loops in the model.
Protect Internal Edges: Performs thin sweep preserving the interior loops in the model.
Element Option: Instructs the solver which the element option to be used. The default option is Solid Shell. The available options are Solid Shell and Solid.
Solid Shell: Instructs the solver to use the solid shell elements where possible.
Solid: Instructs the solver to always use a solid element.
Control Messages: Provides message when the sweep method fails.
Advanced
Sweep Bias Type: Specify bias in the same manner as edge biasing for the Bias Type setting in a Sizing mesh control. There is no graphical feedback for biasing on a Method control. Biasing direction is from the source to the target.
Note: Sweep Bias Type is not available for Axisymmetric algorithm.
Mesh Based Defeaturing: Enable or disable the defeaturing of small features. The default value is Off. The available options are On and Off. When Mesh Based Defeaturing is On, features smaller than or equal to the value of Defeature Size are removed automatically.
Defeature Size: Specifies the tolerance value for defeaturing.
Fall-Back Mesh Type: Provides the option to select the mesh type to be used when the Axisymmetric Sweep fails. The default option is Program Controlled. The available options are:
Program Controlled: Provides error message when Axisymmetric Sweep fails unless you choose tetrahedral meshing.
None: Provides error message when Axisymmetric Sweep fails.
Tetrahedrons: Generates tetrahedral mesh when Axisymmetric Sweep fails.
Constrain Boundary: Specifies whether you want to allow the mesher to split the elements at the boundary of a swept mesh region to aid in meshing. Available for multibody parts only (both for general sweeping and thin sweeping). When Constrain Boundary is , does not split the elements at the boundary while sweep meshing. (constrain boundary, no splitting is allowed). When Constrain Boundary is , splits the elements at the boundary while sweep meshing. (do not constrain boundary, splitting is allowed). Choosing prevents tets from entering the swept body. The default is .
Note: Constrain Boundary setting is not available for Axisymmetric algorithm.
Note:
For gasket simulations, set the Stiffness Behavior of the body to Gasket and proceed with adjusting mesh settings as described in the Gasket Meshing section located under Gasket Bodies in the Mechanical application help.
In models with swept regions, the sizing controls will affect the mesh gradation in the swept region. You can override this effect by specifying any Sweep Bias value (including a value of 1), Sweep Element Size value, or Sweep Num Divs value in the Details View when defining the sweep method.
There is a system limitation when using the sweep method with the Size Function. The Size Function may have nodes slightly off because the spacing is queried. The sweeper then tries to match that spacing, which may lead to unexpected mesh results.
If you apply a local Sizing Control to a solid body with a Method control set to Hex Dominant or Sweep, or to a sheet body with a Method control set to Quadrilateral Dominant, a near uniform quadrilateral mesh will result on all affected faces on a body meshed with Hex Dominant, on the source face meshed with Sweep, and on all affected faces meshed with Quadrilateral Dominant. To obtain even more of a uniform quadrilateral mesh, set the Behavior of the Sizing Control to Hard.
Limitations
The limitations for Axisymmetric sweep are as follows:
A warning message appears, when the nodes are off the mesh. You can click the warning message to locate that area on the model and can redefine mesh using Mesh Based Defeaturing for the particular area.
Axisymmetric algorithm does not support Surface of Influence.
Axisymmetric algorithm does not support edge biasing.
Axisymmetric Sweep does not support multibody.
Axisymmetric Sweep cannot handle any body with internal voids.
Axisymmetric Sweep does not support Mixed Order Meshing.