Software for Expanding CAD Functionality in COMSOL Multiphysics®

A detailed view of the stress of a shaft bracket model made of steel material.

Constraints and Dimensions

The Design Module includes a set of sketching tools used for adding constraints and dimensions to planar drawings for 2D models, 3D work planes, and in geometry parts. Some of the available constraint options include parallel, perpendicular, and tangent constraints. For example, to make two polygon segments meet at 90 degrees, you click on the two edges and use a perpendicular constraint. The options for dimensions include, among others, length dimension, radius, and angle. You can, for example, simply click-and-drag an edge to interactively set a length dimension. To aid in creating consistent drawings, the Design Module gives you immediate feedback, whether a sketch is underdefined, overdefined, or well defined.

All of the dimensions detailed above can be made parametric using the general parametric framework in COMSOL Multiphysics^®. This enables you to run parametric sweeps across one or multiple dimensions. Additionally, when combined with the Optimization Module, you can run parametric optimizations, taking full advantage of the parametric functionality.

CAD Import Functionality

The Design Module contains all of the functionality within the CAD Import Module, which is based on importing and exporting a wide range of CAD file formats. To ensure the validity of the imported geometric information, you can automatically (or manually) repair your CAD models and defeature them to help with setting up and running an analysis. Additionally, this includes associative geometry import: when an updated file is imported, the software reads information in the CAD files to identify the geometric entities in the file and compares it with a previously imported version of the file. In this way, physics and other settings on the geometry are retained to the greatest extent possible. For more information on these features and functionality, see the CAD Import Module page.

The COMSOL Multiphysics UI showing the Model Builder with the Geometry node selected, the Delete Holes operation settings, and a geometry of a cover plate with holes of various sizes in the Graphics window.

Geometric Operations in the Design Module

The Design Module offers functionality for creating and modifying geometry as well as more advanced Boolean operations.

Fillet

Fillets are created by simply clicking on one or more edges and specifying a radius. This will create rounded corners on the selected set of edges and is used, for example, in structural mechanics to avoid stress concentrations and in electromagnetics to avoid electric breakdown.

Offset Faces

The Offset Faces operation is used to offset faces on 3D geometry objects along their normal direction. This feature is also useful for editing 3D geometries and enables the parameterization of geometric features in objects imported from 3D CAD files. In MEMS applications, this operation can be used for creating 3D geometries in a way that emulates the deposition of materials onto nonflat surfaces.

Midsurface

The Midsurface operation removes the thickness of a solid object having constant thickness, resulting in a surface object. Such surface objects are typically used with a Shell interface where the thickness is represented as a physics property instead of a geometric feature.

Loft

The Loft operation enables the creation of a loft surface using specified profile and guide curves. This surface is formed from one or several faces that interpolate between the profiles. The operation is particularly useful for generating smooth geometric transitions among profile curves with varying shapes.

Chamfer

Chamfers are created by simply clicking on an edge and specifying a distance. This will create beveled corners at the selected edges.

Transform Faces

The Transform Faces operation applies a linear transformation to selected faces on 3D geometry objects. This transformation can include displacement, rotation, and isotropic scaling. Its functionality becomes particularly useful when working with models imported from 3D CAD files. For example, the operation allows for the parameterization of geometric features in imported objects, sweeps over parameters, and the optimization of designs when used with the Optimization Module.

Thicken

The Thicken operation is used to convert a surface object to a solid object by giving it a thickness, usually in the normal direction.

A closeup view of the Geometry settings and a turbine model in the Graphics window.

Advanced Boolean Operations

The Design Module provides more advanced Boolean operations that are expected to yield better results for more complex geometry models, for example, when computing the union of objects having touching faces that do not match exactly.

Design Module

Constraints and Dimensions

CAD Import Functionality