structuralSEInterface

(To be removed) Specify structural superelement interface for component mode synthesis

structuralSEInterface will be removed. Use romInterface instead. (since R2023a) For more information on updating your code, see Version History.

Syntax

structuralSEInterface(structuralmodel,RegionType,RegionID)

sei = structuralSEInterface(___)

Description

structuralSEInterface(structuralmodel,RegionType,RegionID) defines the specified geometric region RegionType, RegionID as a superelement interface for component mode synthesis. For better performance, specify geometric regions with a minimal number of nodes. For example, use a set of edges instead of a face, or a set of vertices instead of an edge.

If you intend to use a reduced-order model in Simscape™ Multibody™, use structuralBC instead of structuralSEInterface.

sei = structuralSEInterface(___) returns the superelement interface assignment object using the previous syntax.

Examples

Superelement Interfaces for Component Mode Synthesis

Define the two ends of the beam as structural superelement interfaces. The reduced-order modeling technique retains the degrees of freedom on these boundaries while condensing all other degrees of freedom.

Create a structural model for modal analysis of a 3-D problem.

structuralmodel = createpde("structural","modal-solid");

Create a geometry and include it in the model. Plot the geometry.

gm = multicuboid(0.1,0.01,0.01);
structuralmodel.Geometry = gm;
pdegplot(structuralmodel,"EdgeLabels","on","FaceAlpha",0.5)

Specify Young's modulus, Poisson's ratio, and the mass density of the material.

structuralProperties(structuralmodel,"YoungsModulus",70E9, ...
                                     "PoissonsRatio",0.3, ...
                                     "MassDensity",2700);

Generate a mesh.

generateMesh(structuralmodel);

Specify the ends of the beam as structural superelement interfaces. For better performance, use the set of edges bounding each side of the beam instead of using the entire face.

structuralSEInterface(structuralmodel,"Edge",[4,6,9,10]);
structuralSEInterface(structuralmodel,"Edge",[2,8,11,12]);

Reduce the model to all modes in the frequency range [-Inf,500000] and the interface degrees of freedom.

R = reduce(structuralmodel,"FrequencyRange",[-Inf,500000])

R = 
  ReducedStructuralModel with properties:

                     K: [166×166 double]
                     M: [166×166 double]
              NumModes: 22
           RetainedDoF: [144×1 double]
    ReferenceLocations: []
                  Mesh: [1×1 FEMesh]

Input Arguments

structuralmodel — Structural model

StructuralModel object

Structural model, specified as a StructuralModel object. The model contains the geometry, mesh, structural properties of the material, body loads, boundary loads, and boundary conditions.

Example: structuralmodel = createpde("structural","transient-solid")

RegionType — Geometric region type

"Vertex" | "Edge" | "Face" (for a 3-D model only)

Geometric region type, specified as "Vertex", "Edge", or, for a 3-D model, "Face".

Example: structuralSEInterface(structuralmodel,"Face",[2,5])

Data Types: char | string

RegionID — Geometric region ID

vector of positive integers

Geometric region ID, specified as a vector of positive integers. Find the region IDs by using pdegplot.

Example: structuralSEInterface(structuralmodel,"Face",[2,5])

Data Types: double

Output Arguments

sei — Handle to superelement interface

StructuralSEIAssignment object

Superelement interface assignment, returned as a StructuralSEIAssignment object. See StructuralSEIAssignment Properties.

Version History

Introduced in R2019b

R2025a: To be removed

structuralSEInterface will be removed. Use romInterface instead.

For example, you can specify the fixed and loaded boundaries as structural superelement interfaces by creating a romInterface object for each superelement interface. In this case, the reduced order model retains the degrees of freedom (DoFs) on the fixed face and the loaded vertex while condensing all other DoFs in favor of modal DoFs.

gm = multicuboid(0.1,0.01,0.01);
model = femodel(AnalysisType="structuralModal", ...
                Geometry=gm);
romObj1 = romInterface(Edge=[4 6 9 10]);
romObj2 = romInterface(Edge=[2 8 11 12]);
model.ROMInterfaces = [romObj1,romObj2];

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 and Reduced-Order Modeling Technique for Beam with Point Load.