findThermalProperties

Find thermal material properties assigned to a geometric region

Domain-specific heat transfer workflow is not recommended. New features might not be compatible with this workflow. For help migrating your existing code to the unified finite element workflow, see Migration from Domain-Specific to Unified Workflow.

Syntax

tmpa = findThermalProperties(materialProperties,RegionType,RegionID)

Description

tmpa = findThermalProperties(materialProperties,RegionType,RegionID) returns thermal material properties tmpa assigned to the specified region.

Examples

Find Thermal Conductivity, Mass Density, and Specific Heat for Faces of 2-D Geometry

Create a transient thermal model that has three faces.

thermalmodel = createpde("thermal","transient");
geometryFromEdges(thermalmodel,@lshapeg);
pdegplot(thermalmodel,"FaceLabels","on")
ylim([-1.1,1.1])
axis equal

For face 1, specify the following thermal properties:

• Thermal conductivity is $10\mathrm{W}/\left(\mathrm{m}{\cdot }^{\circ }\mathit{C}\right)$

• Mass density is $1\mathrm{kg}/{\mathrm{m}}^3$

• Specific heat is $0.1\mathrm{J}/\left(\mathrm{kg}{\cdot }^{\circ }\mathrm{C}\right)$

thermalProperties(thermalmodel,"ThermalConductivity",10,...
                               "MassDensity",1,...
                               "SpecificHeat",0.1,...
                               "Face",1);

For face 2, specify the following thermal properties:

• Thermal conductivity is $20\mathrm{W}/\left(\mathrm{m}{\cdot }^{\circ }\mathit{C}\right)$

• Mass density is $2\mathrm{kg}/{\mathrm{m}}^3$

• Specific heat is $0.2\mathrm{J}/\left(\mathrm{kg}{\cdot }^{\circ }\mathrm{C}\right)$

thermalProperties(thermalmodel,"ThermalConductivity",20,...
                               "MassDensity",2,...
                               "SpecificHeat",0.2,...
                               "Face",2);

For face 3, specify the following thermal properties:

• Thermal conductivity is $30\mathrm{W}/\left(\mathrm{m}{\cdot }^{\circ }\mathit{C}\right)$)

• Mass density is $3\mathrm{kg}/{\mathrm{m}}^3$

• Specific heat is $0.3\mathrm{J}/\left(\mathrm{kg}{\cdot }^{\circ }\mathrm{C}\right)$

thermalProperties(thermalmodel,"ThermalConductivity",30,...
                               "MassDensity",3,...
                               "SpecificHeat",0.3,...
                               "Face",3);

Check the material properties specification for face 1.

mpaFace1 = findThermalProperties(thermalmodel.MaterialProperties, ...
                                                        "Face",1)

mpaFace1 = 
  ThermalMaterialAssignment with properties:

             RegionType: 'face'
               RegionID: 1
    ThermalConductivity: 10
            MassDensity: 1
           SpecificHeat: 0.1000

Check the heat source specification for faces 2 and 3.

mpa = findThermalProperties(thermalmodel.MaterialProperties, ...
                                              "Face",[2,3]);
mpaFace2 = mpa(1)

mpaFace2 = 
  ThermalMaterialAssignment with properties:

             RegionType: 'face'
               RegionID: 2
    ThermalConductivity: 20
            MassDensity: 2
           SpecificHeat: 0.2000

mpaFace3 = mpa(2)

mpaFace3 = 
  ThermalMaterialAssignment with properties:

             RegionType: 'face'
               RegionID: 3
    ThermalConductivity: 30
            MassDensity: 3
           SpecificHeat: 0.3000

Find Thermal Conductivity for Cells of 3-D Geometry

Create a geometry that consists of three stacked cylinders and include the geometry in a thermal model.

gm = multicylinder(10,[1 2 3],"ZOffset",[0 1 3])

gm = 
  DiscreteGeometry with properties:

       NumCells: 3
       NumFaces: 7
       NumEdges: 4
    NumVertices: 4
       Vertices: [4x3 double]

thermalmodel = createpde("thermal");
thermalmodel.Geometry = gm;
pdegplot(thermalmodel,"CellLabels","on","FaceAlpha",0.5)

Thermal conductivity of the cylinder C1 is $10\mathrm{W}/\left(\mathrm{m}{\cdot }^{\circ }\mathrm{C}\right)$.

thermalProperties(thermalmodel,"ThermalConductivity",10,"Cell",1);

Thermal conductivity of the cylinder C2 is $20\mathrm{W}/\left(\mathrm{m}{\cdot }^{\circ }\mathrm{C}\right)$.

thermalProperties(thermalmodel,"ThermalConductivity",20,"Cell",2);

Thermal conductivity of the cylinder C3 is $30\mathrm{W}/\left(\mathrm{m}{\cdot }^{\circ }\mathrm{C}\right)$.

thermalProperties(thermalmodel,"ThermalConductivity",30,"Cell",3);

Check the material properties specification for cell 1:

mpaCell1 = findThermalProperties(thermalmodel.MaterialProperties, ...
                                                        "Cell",1)

mpaCell1 = 
  ThermalMaterialAssignment with properties:

             RegionType: 'cell'
               RegionID: 1
    ThermalConductivity: 10
            MassDensity: []
           SpecificHeat: []

Check the heat source specification for cells 2 and 3:

mpa = findThermalProperties(thermalmodel.MaterialProperties,"Cell",2:3);
mpaCell2 = mpa(1)

mpaCell2 = 
  ThermalMaterialAssignment with properties:

             RegionType: 'cell'
               RegionID: 2
    ThermalConductivity: 20
            MassDensity: []
           SpecificHeat: []

mpaCell3 = mpa(2)

mpaCell3 = 
  ThermalMaterialAssignment with properties:

             RegionType: 'cell'
               RegionID: 3
    ThermalConductivity: 30
            MassDensity: []
           SpecificHeat: []

Input Arguments

materialProperties — Material properties of the model

MaterialProperties property of a thermal model

Material properties of the model, specified as the MaterialProperties property of a thermal model.

Example: thermalmodel.MaterialProperties

RegionType — Geometric region type

"Face" for a 2-D model | "Cell" for a 3-D model

Geometric region type, specified as "Face" or "Cell".

Example: findThermalProperties(thermalmodel.MaterialProperties,"Cell",1)

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: findThermalProperties(thermalmodel.MaterialProperties,"Face",1:3)

Data Types: double

Output Arguments

tmpa — Material properties assignment

ThermalMaterialAssignment object

Material properties assignment, returned as a ThermalMaterialAssignment object. See ThermalMaterialAssignment Properties.

Version History

Introduced in R2017a