findStructuralDamping

(To be removed) Find damping model assigned to structural dynamics model

findStructuralDamping will be removed. To find Rayleigh damping parameters of the model, use the DampingAlpha and DampingBeta properties of femodel instead. (since R2023a) For more information on updating your code, see Version History.

Syntax

dma = findStructuralDamping(dampingModels)

Description

dma = findStructuralDamping(dampingModels) returns the damping model and its parameters assigned to the entire structural dynamics model. The toolbox supports the proportional (Rayleigh) damping model and the modal damping model. The parameters of the proportional damping model are the mass and stiffness proportional damping parameters. The parameter of the modal damping model is the modal damping ratio.

Use this function to find which damping model and parameters are currently active if you made multiple damping assignments.

Examples

Find Damping Model Assignment

Find the damping model assignment for a 3-D model.

Create a transient structural model.

structuralModel = createpde("structural","transient-solid");

Import and plot the geometry.

importGeometry(structuralModel,"Block.stl");
pdegplot(structuralModel,"CellLabels","on")

Specify the stiffness proportional damping parameter.

structuralDamping(structuralModel,"Beta",40);

Now specify the mass proportional damping parameter.

structuralDamping(structuralModel,"Alpha",10);

Check the damping parameter assignment for structuralModel. Notice that the Beta parameter is empty.

findStructuralDamping(structuralModel.DampingModels)

ans = 
  StructuralDampingAssignment with properties:

      RegionType: 'Cell'
        RegionID: 1
    DampingModel: "proportional"
           Alpha: 10
            Beta: []
            Zeta: []

When you specify damping parameters by calling the structuralDamping function several times, the toolbox uses the last assignment. Specify both the mass and stiffness parameters.

structuralDamping(structuralModel,"Alpha",10,"Beta",40);

Check the damping parameter assignment for structuralModel.

findStructuralDamping(structuralModel.DampingModels)

ans = 
  StructuralDampingAssignment with properties:

      RegionType: 'Cell'
        RegionID: 1
    DampingModel: "proportional"
           Alpha: 10
            Beta: 40
            Zeta: []

Input Arguments

dampingModels — Damping model

DampingModels property of StructuralModel object

Damping model of the structural model, specified as a DampingModels property of a StructuralModel object.

Example: structuralmodel.DampingModels

Output Arguments

dma — Damping model assignment

StructuralDampingAssignment object

Damping model assignment, returned as a StructuralDampingAssignment object. For details, see StructuralDampingAssignment Properties.

Version History

Introduced in R2018a

R2025a: To be removed

findStructuralDamping will be removed. To find Rayleigh damping parameters of the model, use the DampingAlpha and DampingBeta properties of femodel instead.

For example, you can check the Rayleigh damping parameters as follows.

 model = femodel(AnalysisType="structuralTransient", ...
                 Geometry="SquareBeam.stl");
model.DampingAlpha = 10;
model.DampingBeta = 2;
model.DampingAlpha
model.DampingBeta

Modal damping is specified as the DampingZeta argument of the solve function. This parameter is not stored within femodel.

The unified finite element model workflow defines the type of a problem and all of its parameters as the properties of an femodel object. This object enables you to specify physical parameters for structural, thermal, and electromagnetic types of analyses. The solver in the unified workflow uses only the parameters (properties) appropriate for the current analysis type while ignoring all other properties. If you switch the analysis type by setting the AnalysisType property of the model, the solver uses the appropriate set of properties corresponding to the new analysis type.

For more help migrating your existing code that uses StructuralModel to the unified finite element workflow, see Migration from Domain-Specific to Unified Workflow.