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interpolateAcceleration

Interpolate acceleration at arbitrary spatial locations for all time or frequency steps for dynamic structural model

Description

intrpAccel = interpolateAcceleration(structuralresults,xq,yq) returns the interpolated acceleration values at the 2-D points specified in xq and yq for all time or frequency steps.

example

intrpAccel = interpolateAcceleration(structuralresults,xq,yq,zq) uses the 3-D points specified in xq, yq, and zq.

intrpAccel = interpolateAcceleration(structuralresults,querypoints) uses the points specified in querypoints.

Examples

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Interpolate acceleration at the geometric center of a beam under a harmonic excitation

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

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

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

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

Figure contains an axes object. The axes object contains 6 objects of type quiver, text, patch, line.

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

structuralProperties(structuralmodel,"YoungsModulus",210E9, ...
                                     "PoissonsRatio",0.3, ...
                                     "MassDensity",7800);

Fix one end of the beam.

structuralBC(structuralmodel,"Face",5,"Constraint","fixed");

Apply a sinusoidal displacement along the y-direction on the end opposite the fixed end of the beam.

structuralBC(structuralmodel,"Face",3,...
                             "YDisplacement",1E-4, ...
                             "Frequency",50);

Generate a mesh.

generateMesh(structuralmodel,"Hmax",0.01);

Specify the zero initial displacement and velocity.

structuralIC(structuralmodel,"Displacement",[0;0;0], ...
                             "Velocity",[0;0;0]);

Solve the model.

tlist = 0:0.002:0.2;
structuralresults = solve(structuralmodel,tlist);

Interpolate acceleration at the geometric center of the beam.

coordsMidSpan = [0;0;0.005];
intrpAccel = interpolateAcceleration(structuralresults,coordsMidSpan);

Plot the y-component of acceleration of the geometric center of the beam.

figure
plot(structuralresults.SolutionTimes,intrpAccel.ay)
title("Y-Acceleration of the Geometric Center of the Beam")

Figure contains an axes object. The axes object with title Y-Acceleration of the Geometric Center of the Beam contains an object of type line.

Input Arguments

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Solution of the dynamic structural analysis problem, specified as a TransientStructuralResults or FrequencyStructuralResults object. Create structuralresults by using the solve function.

Example: structuralresults = solve(structuralmodel,tlist)

x-coordinate query points, specified as a real array. interpolateAcceleration evaluates accelerations at the 2-D coordinate points [xq(i),yq(i)] or at the 3-D coordinate points [xq(i),yq(i),zq(i)]. Therefore, xq, yq, and (if present) zq must have the same number of entries.

interpolateAcceleration converts the query points to column vectors xq(:), yq(:), and (if present) zq(:). The function returns accelerations as an FEStruct object with the properties containing vectors of the same size as these column vectors. To ensure that the dimensions of the returned solution are consistent with the dimensions of the original query points, use the reshape function. For example, use intrpAccel = reshape(intrpAccel.ux,size(xq)).

Data Types: double

y-coordinate query points, specified as a real array. interpolateAcceleration evaluates accelerations at the 2-D coordinate points [xq(i),yq(i)] or at the 3-D coordinate points [xq(i),yq(i),zq(i)]. Therefore, xq, yq, and (if present) zq must have the same number of entries. Internally, interpolateAcceleration converts the query points to the column vector yq(:).

Data Types: double

z-coordinate query points, specified as a real array. interpolateAcceleration evaluates accelerations at the 3-D coordinate points [xq(i),yq(i),zq(i)]. Therefore, xq, yq, and zq must have the same number of entries. Internally, interpolateAcceleration converts the query points to the column vector zq(:).

Data Types: double

Query points, specified as a real matrix with either two rows for 2-D geometry or three rows for 3-D geometry. interpolateAcceleration evaluates accelerations at the coordinate points querypoints(:,i), so each column of querypoints contains exactly one 2-D or 3-D query point.

Example: For 2-D geometry, querypoints = [0.5,0.5,0.75,0.75; 1,2,0,0.5]

Data Types: double

Output Arguments

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Accelerations at the query points, returned as an FEStruct object with the properties representing spatial components of acceleration at the query points. For query points that are outside the geometry, intrpAccel returns NaN. Properties of an FEStruct object are read-only.

Version History

Introduced in R2018a