A model component is a fundamental part of the model and contains a geometry with its associated physics interface, mesh, and variables and other definitions that are local to that component. The Component node defines the namespace for each part of a model that is defined in a model component. A model can have several
Component nodes. For example, if you are setting up a system model using both a 2D simplification — represented in one 2D
Component branch — and a full 3D description in another
Component, these can both be added to the Model Builder to represent different aspects or parts of the model. You can couple variables between different components in a model using coupling operators.
The Component node icon also indicates the space dimension:.
You can create models with multiple geometries by adding one or more Component nodes to the Model Builder. Typically a component is added to the model in the Model Wizard when you select a space dimension.
To copy a component with all its subnodes, right-click the Component node and choose
Copy (or, for Windows users, click
Copy on the Quick Access Toolbar). You can then paste it in the same or a new COMSOL Desktop session by right-clicking the root node and choosing
Paste Multiple Items (or, for Windows users, click
Paste Multiple Items on the Quick Access Toolbar).
It is also possible to insert components from another COMSOL Multiphysics model. To do so, right-click the top node (root node) and choose Insert Components from Model. An
Insert Components dialog box appears where you can browse or type the path and name of the COMSOL Multiphysics model file from which you want to insert components in the
Model field. Select one or more of the components in the model from the
Components list and then click
OK to insert them into the current model.
In a model with more than one component, you can switch the focus to another component by selecting from the list of components in the Home toolbar’s
Model section. You can also switch to another component by clicking its
Component node in the model tree (or any other node inside that component).
The Settings window has the following sections (also see
Figure 3-3):
The default setting in the Unit system list,
Same as global system, is to use the global unit system, which you specify in the root node’s
Settings window. If you want to use another unit system in a model, select it from this list.
For Spatial frame coordinates, the default names are
x,
y, and
z for 3D as well as planar 1D and 2D geometries. For axisymmetric geometries, the default names for the spatial frame coordinates are
r,
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(
phi), and
z. If you use the geometry to represent something other than space, or if you for some other reason want to use other names for the spatial coordinates, you can change the names in the fields for the
First,
Second, and
Third coordinate under
Spatial frame coordinates.
For Material frame coordinates, the default names are
X,
Y, and
Z for 3D as well as planar 1D and 2D geometries. For axisymmetric geometries, the default names for the material frame coordinates are
R,
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(
PHI), and
Z. You can change the names in the fields for the
First,
Second, and
Third coordinate under
Material frame coordinates.
For Geometry frame coordinates, the default names are
Xg,
Yg, and
Zg for 3D as well as planar 1D and 2D geometries. For axisymmetric geometries, the default names for the geometry frame coordinates are
Rg,
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(
PHIg), and
Zg. You can change the names in the fields for the
First,
Second, and
Third coordinate under
Geometry frame coordinates.
For Mesh frame coordinates, the default names are
Xm,
Ym, and
Zm for 3D as well as planar 1D and 2D geometries. For axisymmetric geometries, the default names for the mesh frame coordinates are
Rm,
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(
PHIm), and
Zm. You can change the names in the fields for the
First,
Second, and
Third coordinate under
Mesh frame coordinates.
The setting in the Geometry shape order list determines the order of the curved mesh elements that determine the geometry shape. The default setting is
Automatic, but it is also possible to select an order such as
Linear,
Quadratic,
Cubic,
Quartic,
Quintic,
Sextic, and
Septic. The default setting allows for automatic reduction of the order in some cases.