COMSOL 6.4 - Face Load

Face Load

Add a 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 7-47: 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.

Coordinate System Selection

The list contains all applicable coordinate systems in the model, including the and the . The is selected by default. Face loads are specified along the axes of the selected coordinate system.

Force

Select a — , , , or . Then enter values or expressions for the components in the matrix based on the selection and the space dimension.

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For and , the traction components are given explicitly.

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For , 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 . 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 , 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 7-48: Load types.
Load Type	variable	SI unit
Force per reference area	fA	N/m2
Force per deformed area	fa	N/m2
Total force	Ftot	N
Pressure	p	Pa

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See Defining a Layer Local System in the Composite Materials Modeling chapter.

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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 , the list normally only contains . 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

Ribbon

Physics tab with selected: