The Added Mass node is available on different geometrical entity levels and can be used to supply inertia that is not part of the material itself. Such inertia does not need to be isotropic in the sense that the inertial effects are not the same in all directions.

The Added Mass node is only available with some COMSOL products (see https://www.comsol.com/products/specifications/).

This section is only present in the Added Mass node in the Shell interface.

Select a Mass type using Table 4-14 as a guide. The default option is the type for the geometric entity. The added mass matrix can be entered as Isotropic, Diagonal, or Symmetric. For Isotropic the same mass is used in all the diagonal elements of the mass matrix.

Select the Exclude contribution check box to switch off the loads generated by this node when the frame is accelerated using a Gravity, Rotating Frame, Linearly Accelerated Frame, or Base Excitation feature. The setting will also determine whether the node will contribute when computing mass properties and participation factors.

Physics tab with Solid Mechanics selected:

Physics tab with Shell or Membrane selected:

Physics tab with Plate selected:

Physics tab with Layered Shell selected:

Physics tab with Beam, Truss, or Wire selected:

Physics tab with Multibody Dynamics selected: