Geometry Updates

COMSOL Multiphysics® version 5.5 brings extensive improvements to geometry modeling with new sketching tools. On top of this, there are several updates to the general functionality, including new transform operations, and new parts in the Part Libraries. Read more about these updates below.

New Sketching Tools

A set of new sketching tools for planar drawings are available when working with 2D geometry models and 3D work planes. On the new Sketch toolbar there are options for drawing polygons, circular arcs, interpolation curves, Bezier curves, rectangles, squares, circles, and ellipses. These drawing options are completely new versions of the corresponding functionality available in earlier versions of COMSOL Multiphysics®.

A cropped screenshot showing the Sketch tab open in COMSOL Multiphysics version 5.5. Using the Sketch tab The new Sketch tab with various tools for creating planar drawings.

A new polygon tool lets you move points and lines interactively by clicking and dragging. When editing point coordinates, the corresponding point is highlighted with a red circle in the Graphics window. Similarly, a new tool for creating an interpolation curve allows you to interactively draw the curve. To edit the curve, you can either drag a point in the Graphics window or change the point coordinate in a table. While dragging a point, a green guideline indicates alignment with other points, available for several of the new sketching tools.

The Settings window for the Interpolation Curve tool is shown next to the Graphics window showing the sketch and a green guideline. Using the interactive interpolation curve tool The new interactive interpolation curve tool with a green guideline indicating alignment between points.

The tools for drawing squares, rectangles, circles, and ellipses have new options for interactive editing. Auxiliary points and lines are associated with the geometry primitives, including circular arcs, that aid in interactively changing the object's parameters by clicking and dragging. For example, when using the mouse to drag an entity, you can press Ctrl and/or Shift to change how the other entities move. In a similar way, the new tools for creating Bezier curves can be drawn and edited interactively. The snapping functionality has been improved and extended to include snapping to existing lines and circles as well as the possibility of snapping lines and circles that you draw to existing points, lines, and circles. Additionally, when you have multiple features in the sketch, you can double-click on a highlighted vertex or edge to open the corresponding Settings window for that feature.

Three new options for creating circular arcs are available for various input combinations: Start, Center, Angle, Start, Tangent, End, and Start Middle, End. A new Sketch Fillet operation lets you interactively drag a fillet starting from a corner. The fillet radius will be determined by the mouse release point and can be subsequently edited.

If you have a license for the Design Module, the Sketch tab also contains buttons for using geometric constraints and dimensions. See the Design Module release highlights page for more information.

The Plane Geometry settings are shown next to a sketched circular arc in the Graphics window. Sketching a circular arc A circular arc defined with the new option for specifying start point, tangent, and end point.

New Rotate, Move, and Copy Options

There are now more ways to rotate 3D geometry objects with the Rotate feature: you can choose to specify an axis and rotation or to specify Euler angles. This option is also available in Work Plane features defined using the Transformed plane type and in the Part Instance nodes in the Position and Orientation of Output section. The Move and Copy features now include a Specify list in the Displacement section with the options Displacement vector and Positions. This makes it possible to specify the move using a vertex or coordinates for the old position and vertices or coordinates for the location to move and copy to.

New Rigid Transform Operation

A new feature, Rigid Transform, does both translation and rotation in 3D. You can specify the transformation by matching two work planes, which eliminates the need to compute the rotation axis and angle. Alternatively, you can use settings similar to the Move and Rotate features and combine translation and rotation operations to specify the transformation. This feature can be useful for positioning imported objects.

The COMSOL Multiphysics UI showing the Model Builder, Rigid Transform feature settings, and a hinge assembly model in the Graphics window. Using a Rigid Transform feature A Rigid Transform feature applied to a hinge assembly model by matching the location and orientation of two Work Planes.

Specify Work Plane by Vertex and Normal Vector

You can now specify a work plane by giving its normal vector and a point or vertex in the plane. Together with the Rigid Transform feature, this makes it possible to orient an object so that one of its planar faces gets a prescribed normal vector.

New End Condition for Interpolation Curve

In the Interpolation Curve feature, you can now choose to use no end condition instead of a given tangent direction or zero curvature. The shape of the curve changes slightly for the open curve case due to a new underlying curve parameterization scheme.

New Geometry Parts in the Part Library

The Part Library for COMSOL Multiphysics® has been extended to include the five platonic solids (cube, tetrahedron, octahedron, dodecahedron, and icosahedron), as well as a propeller with constant pitch and a random flat surface.

The COMSOL Multiphysics Part Libraries, showing the new Platonic Solids options, with the icosahedron selected. The icosahedron geometry part The new icosahedron part instance in the COMSOL Multiphysics® Part Library.
The COMSOL Multiphysics Part Libraries, showing the new Random Surfaces option: Random Flat Surface. The Random Flat Surface geometry part The new random flat surface part in the COMSOL Multiphysics® Part Library.

Automatic Removal of Narrow Face Regions

The Remove Details operation has expanded functionality to automatically remove narrow face regions from your geometry. By making sure that the Narrow face regions check box is selected (it is selected by default), located in the Details to Remove section, the operation will find and remove any narrow face region from your geometry automatically. You can see this new feature in the Fluid-Structure Interaction in Aluminum Extrusion model.

The COMSOL Multiphysics UI showing the new remove narrow face regions check box, and two meshes in the Graphics window, one with the narrow face, and one with the narrow face removed. Removing narrow face regions automatically Select the Narrow face regions check box in the Details to Remove section to find and remove them from your geometry. Shown are a face with narrow regions inducing additional mesh refinement and bad element quality (red) and the resulting face after automatic removal of the narrow regions (cyan).