findStructuralIC

Find initial displacement and velocity assigned to geometric region

Syntax

sica = findStructuralIC(structuralmodel.InitialConditions,RegionType,RegionID)

Description

sica = findStructuralIC(structuralmodel.InitialConditions,RegionType,RegionID) returns the initial displacement and velocity assigned to the specified region.

Examples

Find Initial Conditions for Cells of 3-D Geometry

Find the initial displacement and velocity assigned to the cells of a 3-D geometry.

Create a transient dynamic model for a 3-D problem.

structuralmodel = createpde('structural','transient-solid');

Create the geometry consisting of the three nested cylinders and include it in the model. Plot the geometry.

gm = multicylinder([5 10 15],2);
structuralmodel = createpde('structural','transient-solid');
structuralmodel.Geometry = gm;
pdegplot(structuralmodel,'CellLabels','on','FaceAlpha',0.5)

Set the initial conditions for each cell. When you specify only the initial velocity or initial displacement, structuralIC assumes that the omitted parameter is zero.

structuralIC(structuralmodel,'Displacement',[0;0;0],'Velocity',[0;0;0],'Cell',1);
structuralIC(structuralmodel,'Displacement',[0;0.1;0],'Cell',2);
structuralIC(structuralmodel,'Velocity',[0;0.2;0],'Cell',3);

Check the initial condition specification for cell 1.

SICACell1 = findStructuralIC(structuralmodel.InitialConditions,'Cell',1)

SICACell1 = 
  GeometricStructuralICs with properties:

             RegionType: 'Cell'
               RegionID: 1
    InitialDisplacement: [3x1 double]
        InitialVelocity: [3x1 double]

SICACell1.InitialDisplacement

ans = 3×1

     0
     0
     0

SICACell1.InitialVelocity

ans = 3×1

     0
     0
     0

Find Initial Displacement Set as Previously Obtained Static Solution

Use a static solution as an initial condition for a dynamic structural model. Check and plot the initial displacement.

Create a static model.

staticmodel = createpde('structural','static-solid');

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

gm = multicuboid(0.06,0.005,0.01);
staticmodel.Geometry = gm;
pdegplot(staticmodel,'FaceLabels','on','FaceAlpha',0.5)
view(50,20)

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

structuralProperties(staticmodel,'YoungsModulus',210E9, ...
                                 'PoissonsRatio',0.3,...
                                 'MassDensity',7800);

Apply the boundary condition and static load.

structuralBC(staticmodel,'Face',5,'Constraint','fixed');
structuralBoundaryLoad(staticmodel,'Face',3,'SurfaceTraction',[0;1E6;0]);
generateMesh(staticmodel,'Hmax',0.02);
Rstatic = solve(staticmodel);

Create a dynamic model and assign geometry.

dynamicmodel = createpde('structural','transient-solid');
gm = multicuboid(0.06,0.005,0.01);
dynamicmodel.Geometry = gm;

Apply the boundary condition.

structuralBC(dynamicmodel,'Face',5,'Constraint','fixed');

Specify the initial condition using the static solution.

generateMesh(dynamicmodel,'Hmax',0.02);
structuralIC(dynamicmodel,Rstatic)

ans = 
  NodalStructuralICs with properties:

    InitialDisplacement: [113x3 double]
        InitialVelocity: [113x3 double]

Check the initial condition specification for dynamicmodel.

sica = findStructuralIC(dynamicmodel.InitialConditions,'Cell',1)

sica = 
  NodalStructuralICs with properties:

    InitialDisplacement: [113x3 double]
        InitialVelocity: [113x3 double]

Plot the z-component of the initial displacement.

pdeplot3D(dynamicmodel,'ColorMapData',sica.InitialDisplacement(:,3))
title('Initial Displacement in the Z-direction')

Input Arguments

structuralmodel.InitialConditions — Initial conditions

InitialConditions property of a StructuralModel object

Initial conditions of a transient structural model, specified as the InitialConditions property of a StructuralModel object.

RegionType — Geometric region type

'Face' | 'Edge' | 'Vertex' | 'Cell' for a 3-D model

Geometric region type, specified as 'Face', 'Edge', or 'Vertex' for a 2-D model or 3-D model, or 'Cell' for a 3-D model.

Data Types: char

RegionID — Geometric region ID

vector of positive integers

Geometric region ID, specified as a vector of positive integers. Find the region IDs using pdegplot, as shown in Create Geometry and Remove Face Boundaries or STL File Import.

Data Types: double

Output Arguments

sica — Structural initial condition assignment

GeometricStructuralICs object | NodalStructuralICs object

Structural initial condition for a particular region, returned as a GeometricStructuralICs or NodalStructuralICs object. For details, see GeometricStructuralICs Properties and NodalStructuralICs Properties.