# COMSOL MULTIPHYSICS 5.2a RELEASE HIGHLIGHTS

## Geometry and Mesh Updates

COMSOL Multiphysics® version 5.2a brings many geometry and mesh updates. For instance, there is a new geometry operation to easily partition faces when modeling with structured meshes or to simplify your CAD geometries. There are also improved capabilities for meshing tetrahedral and hexahedral elements. Browse all of the geometry and mesh updates below.

### New Geometry Operation: Partition Faces

The new geometry operation Partition Faces enables you to divide a selected face into multiple faces, using either edges or vertices adjacent to it. For example, you can partition the face of a 3D geometry through the extensions of selected edges of the geometry. This extends an edge into the adjacent face in order to partition that face.

This function serves multiple purposes when modeling, with two examples shown here. In the first case, face partitioning is useful when it would be better to mesh a face with a structured mesh instead of an unstructured mesh, but the face is not suitable for structured (mapped/swept) meshing.

In the second case, when cleaning up complex CAD geometries, you can use face partitioning to eliminate narrow regions of a face. First, use the Partition Faces operation to cut the narrow portion of the face into a separate face. Then, use the Collapse Faces operation to collapse the narrow face.

A Partition Faces node can be placed at any position in the list of subnodes under the Geometry node, which means the operation can partition output geometries, including assembly geometries and virtual geometries, from any subnode.

### Utilize Selections from Work Planes in 3D

Selections created in 2D nodes under Plane Geometry are now available for use in the 3D geometry operations following the work plane. For example, a domain selection created by a Rectangle feature becomes a boundary selection in 3D. If you select Show in physics in the work plane's settings, the selections will also be available for physics, materials, and meshing.

### Cursor Coordinates Displayed When Drawing in 2D

When you draw a 2D geometry, the cursor coordinates of the size of the drawn primitive are now displayed in the status bar at the bottom of the window for reference.

### Improved Quality of Tetrahedral Meshes

The Free Tetrahedral operation has a new element quality optimization algorithm that results in meshes with a higher minimum element quality. The new algorithm offers an option for choosing an optimization level (Basic, Medium, or High), as well as options to avoid creating elements that are too large and prevent inverted curved elements from appearing when computing a study that uses a nonlinear geometry shape order. Additionally, the tetrahedral meshing algorithm has been made more robust and memory efficient.

### Improved Quad Meshing for Specific Geometric Shapes

The Free Quad operation generates more efficient and higher-quality meshes for specific shapes. This feature is available for domains in 2D, as well as for planar faces in 3D that have convex shapes, such as circles and sharp corners.

### Reverse Explicit Distributions

A Reverse direction check box is now available for explicit distributions in the Distribution node. The value of the Reverse direction setting for an edge selection is automatically updated for all of the edges that are altered in the geometry. This means that you do not need to manually redefine explicit distributions for edges that alter direction when you change the geometry.

### Hide and Measure Features for Imported Meshes and Mesh Control Entities

You can now hide entities when working with imported meshes and geometries with mesh control entities. Furthermore, you can measure the length, area, and volume of mesh control entities by using the Measure ribbon button or the Measure settings window.

### Import of ASCII STL Files: Multiple Solids

A broadly accepted extension of the ASCII STL file format supports multiple solids in a single file by including each solid in a `solid... endsolid` section in the file. The import of such files now results in multiple objects according to the number of `solid... endsolid` sections found in the file.