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LabelBlockHT Object

Properties

Methods

Summary

Physical properties of a block for problems of steady-state and transient heat transfer.

Details

The LabelBlockHT object represents physical data applicable to block label for the heat transfer problem.

When you need to set or modify some physical parameters for the block label, you have to get the LabelBlockHT object using the Content property of the Label object, modify the LabelBlockHT object using its properties and then put it back in the Label object assigning your LabelBlockHT to the Content property of your Label object.

The LabelBlockHT object inherits methods and properties from its base class LabelBlock. In addition it provide properties and methods specific for the heat transfer analysis. Those are:

Properties

Kxx

Gets and sets the components of thermal conductivity tensor for linear media in (W/K·m).
Alternatively you use the Spline property (see below) to describe the thermal conductivity as a function of temperature.

Kyy

Spline

Gets and sets a Spline object that represents the thermal conductivity as a function of the temperature. See Using Splines section for details.

Loading

Gets and sets the volume power of the heat source in (W/m3).
Alternatively you use the LoadingSpline property (see below) to describe the thermal conductivity as a function of temperature.

LoadingSpline

Gets and sets the volume power of the heat source as a function of the temperature. See Using Splines section for details.

NonLinearLoading

Returns True if the LoadingSpline is set instead of Loading. In other words, the NonLinearLoading property allows you to know whether the thermal source is depend on the temperature.

MassDensity

Gets and sets the material mass density in (kg/m3).
This parameter is only necessary for transient heat transfer problems.

SpecificHeat

Gets and sets the specific heat in (J/kg·K).
Alternatively you use the SpecificHeatSpline property (see below) to describe the specific heat as a function of temperature.
This parameter is only necessary for transient heat transfer problems.

SpecificHeatSpline

Gets and sets the specific heat as a function of the temperature.
See Using Splines section for details.
This parameter is only necessary for transient heat transfer problems.

NonLinearSpecificHeat

Returns True if the SpecificHeatSpline is set instead of SpecificHeat. In other words, the NonLinearSpecificHeat property allows you to know whether the specific heat is depend on the temperature.

Methods

CreateConductivityCurve

Creates a new empty functional dependency that can be used for describing the the thermal conductivity as a function of temperature.

CreateLoadingCurve

Creates a new empty functional dependency that can be used for describing the volume power of the heat source as a function of the temperature.

CreateSpecificHeatCurve

Creates a new empty functional dependency that can be used for describing the specific heat as a function of the temperature.

You always have to set both Kxx and Kyy properties even for isotropic materials. If the Polar property is set to True, the Kxx component is considered as a radial and Kyy - as tangential component of the thermal conductivity tensor.

Using Splines

Object Spline represents the functional dependency of one variable from another. The LabelBlockHT object can use up to two splines: one for thermal conductivity and the second for the volume power of the heat source as a function of the temperature. You use the Spline property to get or set the conductivity spline and LoadingSpline property to operate with thermal source spline.

To get an existing Spline object you use the Spline or LoadingSpline property. If the spline you need does not yet exist, the Spline or LoadingSpline property returns Nothing. In that case you have to first create a new spline use CreateConductivityCurve or CreateLoadingCurve for conductivity and thermal source respectively.

To enter or modify spline data you use methods and properties of the Spline object. When you are finished with spline data you have to assign the Spline object back to the LabelBlockHT object using Spline or LoadingSpline property.

In the example below we edit the data for the HeatedBody label. Before we start editing the label has a thermal conductivity spline defined and the power of the heat source is given as a constant. We add the additional point (temperature = 400 K, conductivity = 0.65 W/K·m) to the conductivity spline and create a new spline to the thermal source:

Dim lb As QuickField.Label
Dim lbHT As QuickField.LabelBlockHT

Set lb = prb.Labels(qfBlock).Item("HeatedBody")
Set lbHT = lb.Content
With lbHT
    Dim lambda As Spline
    Dim source As Spline

    Set lambda = .Spline
    lambda.Add QF.PointXY(400, 0.65)
    .Spline = lambda

    Set source = .CreateLoadingCurve
    source.Add PointXY(100, 1000)
    source.Add PointXY(200, 800)
    source.Add PointXY(300, 750)
    source.Add PointXY(400, 720)
    .LoadingSpline = source
End With
lb.Content = lbHT