volume

Volume of 3-D mesh elements

Syntax

V = volume(mesh)

[V,VE] = volume(mesh)

V = volume(mesh,elements)

Description

V = volume(mesh) returns the volume V of the entire mesh.

[V,VE] = volume(mesh) also returns a row vector VE containing volumes of each individual element of the mesh.

V = volume(mesh,elements) returns the combined volume of the specified elements of the mesh.

Examples

Volume of 3-D Mesh

Generate a 3-D mesh and find its volume.

Create a PDE model.

model = createpde;

Import and plot the geometry.

importGeometry(model,'BracketWithHole.stl');
pdegplot(model)

Generate a mesh and plot it.

mesh = generateMesh(model);
figure
pdemesh(model)

Compute the volume of the entire mesh.

mv = volume(mesh)

mv = 8.0295e-04

Volume of Individual Elements of 3-D Mesh

Generate a 3-D mesh and find the volume of each element.

Create a PDE model.

model = createpde;

Import and plot the geometry.

importGeometry(model,'BracketWithHole.stl');
pdegplot(model)

Generate a mesh and plot it.

mesh = generateMesh(model);
figure
pdemesh(model)

Compute the volume of the entire mesh and the volume of each individual element of the mesh. Display the volumes of the first 5 elements.

[va,vi] = volume(mesh);
vi(1:5)

ans = 1×5
10-6 ×

    0.5427    0.2243    0.4379    0.2740    0.4541

Total Volume of Group of Elements

Find the combined volume of a group of elements of a 3-D mesh.

Create a PDE model.

model = createpde;

Import and plot the geometry.

importGeometry(model,'BracketWithHole.stl');
pdegplot(model)

Generate a mesh and plot it.

mesh = generateMesh(model);
figure
pdemesh(model)

Evaluate the shape quality of the mesh elements and find the elements with the quality values less than 0.5.

Q = meshQuality(mesh);
elemIDs = find(Q < 0.5);

Compute the total volume of these elements.

mv05 = volume(mesh,elemIDs)

mv05 = 4.2568e-06

Find how much of the total mesh volume belongs to these elements. Return the result as a percentage.

mv05_percent = mv05/volume(mesh)*100

mv05_percent = 0.5301

Input Arguments

mesh — Mesh object

Mesh property of a PDEModel object | output of generateMesh

Mesh object, specified as the Mesh property of a PDEModel object or as the output of generateMesh.

Example: model.Mesh

elements — Element IDs

positive integer | matrix of positive integers

Element IDs, specified as a positive integer or a matrix of positive integers.

Example: [10 68 81 97 113 130 136 164]

Output Arguments

V — Volume

positive number

Volume of the entire mesh or the combined volume of the specified elements of the mesh, returned as a positive number.

VE — Volume of individual elements

row vector of positive numbers

Volume of individual elements, returned as a row vector of positive numbers.