When you add a new Component to the Model Builder, a meshing sequence is added by default in the Mesh node ( or ). You can add more meshing sequences to the Component by right-clicking the Component node and selecting Add Mesh, or by selecting the same option from the The Mesh Toolbar. When a Component has more than one meshing sequence, they are collected under a Meshes node. To add new meshing sequences to such a Component, you can alternatively right-click Meshes.

The Mesh icon () means that the mesh is conforming with the geometric model of the component’s geometry, that is the result of the geometry operations in the component's Geometry node. The Mesh node icon () decorated with the geometry compass means that the meshing sequence defines its own geometric model, for example a mesh sequence where you import a mesh. A green or yellow frame around the Mesh node icon () means that the physics is defined on the geometric model defined by this mesh.

A meshing sequence defines its own geometric model if it contains operations that can change the number of geometric entities, for example by introducing new boundary partitions. Such operations are the ones from the categories Create Entities, Booleans and Partitions, Delete and Join Entities, and the Import operation.

The Mesh node’s Settings window contains the following sections:

From the list, choose Physics-controlled mesh (the default) to let the physics interfaces determine the meshing sequence according to the Physics-Controlled Mesh section below, or choose User-controlled mesh to control the mesh directly using subnodes to this Mesh node, such as Meshing Operations and Attributes.

A mesh sequence that defines its own geometric model is always of the sequence type User-controlled mesh. For a mesh that is conforming with the component’s geometry, the sequence type Physics-controlled mesh is available only when, in the Settings window for the Component, the Geometry is selected from the Physics defined on list.

If you select Physics-controlled mesh in the Sequence type list in the Settings window of a Mesh node and build the meshing sequence, COMSOL Multiphysics creates a mesh that is adapted to the current physics interface settings in the model. The default is to use physics-controlled mesh. For example, for a fluid-flow model you get a somewhat finer mesh than for general physics with a boundary layer mesh along the no-slip boundaries. If you want to modify the overall element size of the physics-induced mesh, select another element size from the Element size list in the Settings window of the main Mesh node and rebuild the mesh. If you change the physics interface settings in the model and rebuild the meshing sequence, COMSOL Multiphysics creates a new mesh adapted to the new physics interface settings.

It is only possible to choose Physics-controlled mesh if the geometry sequence defines the component’s geometric model, on which the physics is applied. A mesh that defines its own geometric model can only have the sequence type User-controlled mesh.

When running a study with adaptation, the solver will automatically set up new adapted meshes which will be noted Controlled by adaptation study and the study will be selected in the list. The mesh will be automatically updated when rerunning the study. Click the button Disconnect from Study and Edit to be able to inspect and edit the meshing sequence. A disconnected mesh will not be updated when rerunning the study. For more information, see Meshes Generated by Adaptation.

This section is only available when the sequence type is set to Physics-controlled mesh.

From the Element size list, choose an element size for the mesh, ranging from Extremely coarse to Extremely fine (default value: Normal).

In the table below, all active physics interfaces, multiphysics couplings, and moving mesh features in the model component appear in the Contributor column. By default, all check boxes under Use are selected so that all listed physics interfaces and moving mesh features contribute to the mesh control suggestions. Clear some of the check boxes if desired to control which physics interfaces and other features that contribute to the physics-controlled mesh. Some physics interfaces may have additional settings for mesh control. A separate section with these settings appears for every such physics interface if its corresponding Use check box is selected. See the documentation for each individual physics interface for more details.

This section is only available when the sequence type is set to User-controlled mesh.

Select the Build new operations automatically check box to allow new operation for this mesh to build automatically. Clear the check box to require that the Build Selected or Build All buttons are pressed in order for the operations to build. The default value is controlled by the preference setting Mesh>Build new operations automatically. Select the In new meshes preference setting to always build operations directly, unless overridden by the settings in the individual Mesh nodes.

When the mesh defines its own geometric model and the physics is defined on this geometric model, the setting Build automatically when leaving mesh appears. This setting controls if the meshing sequence is automatically built (selected by default) when going to another node in the model builder where the geometric model of the mesh is used. For example, when defining materials or physics settings.