Face Load
Add a Face Load to boundaries to use it as a pressure or tangential force acting on a surface. The loads are defined in the given coordinate system.
Interface Selection
Select the interface or interfaces at which the load is to be applied.
Table 6-45: Interface Selections; Face load.
Selection
Apply To
Selection of Individual Interfaces
Boundary
When added: Exterior interfaces.
When Selected Interfaces is selected.
Only exterior interfaces can be selected.
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For a general description of layer and interface selections, see The Shell Properties and Interface Selection Sections.
Force
Select a Load type — Force per unit area, Total force, or Pressure.
Select a Load type — Force per unit area, Pressure, Total force, or for 2D components, Force per unit length. Then enter values or expressions for the components in the matrix based on the selection and the space dimension.
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For Force per unit area, the traction components are given explicitly.
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For Total force, COMSOL Multiphysics then divides the total force by the area of the boundaries where the load is active. Then it is applied in the same way as for a Force per unit area. When working with curved boundaries or local coordinate systems, use this option carefully, as the result is not always intuitive.
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For Pressure, a scalar input is given, and the orientation of the load is along the direction of the shell boundary normal. The sign convention is such that for a positive value of the pressure, the load acts toward the shell, when considered as a solid object. Thus, the orientation of the load is flipped if it is moved from the top side to the bottom side
Table 6-46: Load types.
Load Type
variable
SI unit
Force per unit area
FA
N/m2
Total force
Ftot
N
Pressure
 p
Pa
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The pressure load is a ‘follower load’. The direction changes with deformation in a geometrically nonlinear analysis.
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After selecting a Load type, the Load list normally only contains User defined. When combining with another physics interface, it is also possible to choose a predefined load from this list.
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You can add the Phase subnode to specify the phase of this load in a frequency domain analysis.
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You can specify this load to be a Harmonic Perturbation in a frequency domain analysis.
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You can assign this load to a load group. See Load Cases in the Structural Mechanics Modeling chapter.
Location in User Interface
Context Menus
Layered Shell>Face and Volume Loads>Face Load
Ribbon
Physics tab with Layered Shell selected:
Boundaries>Face and Volume Loads>Face Load