Point Load, Free

Add a node to specifiably concentrated loads with locations specified by coordinates. Such loads do not have to be placed in a geometrical point or in a mesh node. This is particularly useful for the following cases:

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Imported meshes, where there may not be suitable points for load application

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Moving loads

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Several point loads, in which case it may be impractical to create points at all load locations

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For each free point load, there will be a search for the mesh element that is closest to the given location. For the load to be active, the location must be within a certain small distance from at least one element. The actual load location is taken as the point on the element that is closest to the given location. If no element is found, the load is silently ignored.

You can check the number of loads that were ignored through the variable <phys>.<load_tag>.num_ignored, for example solid.plf1.num_ignored.

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The local stress field in the element where a point load acts will not be reliable.

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

Location and Force

Select a — or that determines how the given coordinates are interpreted in case of a geometrically nonlinear analysis. When is selected, the load location on the body is interpreted with respect to the initial configuration. When is selected, then the load location is given in space fixed coordinates, which usually means that the material point on the body where the load is applied will change with deformation even if the coordinate values are constant.

For each row in the table, enter the data for one load. If material frame input is used, then the location is specified in terms of the material coordinates (, , ). If spatial frame input is used, then the spatial coordinates (, , ) are used. Then, enter the force values, , , and . The force vector is interpreted in the coordinate system selected in the section.

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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.


	Pratt Truss Bridge: Application Library path Structural_Mechanics_Module/Beams_and_Shells/pratt_truss_bridge

Location in User Interface

Context Menus

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Physics tab with selected: