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 6-42: 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 — , , or .

Select a — , , , or for 2D components, . Then enter values or expressions for the components in the matrix based on the selection and the space dimension.

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For , 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 6-43:
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 , 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: