Thickness and Offset
Use the Thickness and Offset node to define the thickness for the membrane. In addition to the default Thickness and Offset node always present in the interface, you can add more Thickness and Offset nodes if needed.
If the actual membrane is not located on the selected boundaries, you can also prescribe an offset in the direction of the surface normal. The offset is defined as positive if the membrane is displaced from the meshed boundary in the direction of the positive boundary normal.
Thickness and Offset
Enter a value for the Thickness d of the selected boundaries. The default is 0.0001 m. The thickness can be variable if an expression is used.
Select an option from the Offset definition list — No offset, Relative offset, or Physical offset.
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For No offset, the modeled boundary coincides with the membrane.
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For Relative offset, enter a value or expression in the zrel_offset field for the offset as the ratio between the offset distance and half the membrane thickness. A value of +1 means that the actual membrane bottom surface is located on the meshed boundary, and a value of -1 means that the membrane top surface is located on the meshed boundary.]
Figure 7-1: Meshed boundary indicated in red. The vector n indicates the positive orientation of the boundary normal.
Values of zrel_offset outside the range [-1,1] are also allowed.
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For Physical offset, enter a value or expression in the zoffset field for the actual distance from the meshed boundary to the membrane.
Figure 7-2: Meshed boundary indicated in red. The vector n indicates the positive orientation of the boundary normal.
Thickness and offset settings specified on this node are not applicable for a Layered Linear Elastic Material node as this information is provided on Layered Material, and Layered Material Link nodes.
Location in User Interface
Context Menus
Membrane>Thickness and Offset
Ribbon
Physics tab with Membrane selected:
Boundaries>Membrane>Thickness and Offset