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Coefficient of Linear Thermal Expansion Tab

The material's coefficient of linear thermal expansion is set on this tab.

It is in the [Edit Material Property] dialog box. See [How to Set Body Attribute/Material Property].

 

The isotropic or anisotropic materials can be set up here.

The anisotropic material should be set by the axial vector.

 

 

Given that the coefficient of linear thermal expansion is α, the internal temperature is θ, and the reference temperature is θ0,

 

the initial strain (heat) without temperature dependency is acquired by α multiplied by the temperature change (θ - θ0).

 

α (θ - θ0)

 

The initial strain (heat) with temperature dependency is calculated by integrating α between θ0 and θ.

 

∫α(T) dT: Integration from θ0 to θ

 

The instantaneous coefficient of linear thermal expansion (gradient of the thermal strain at the reference temperature) is used for the temperature-dependent coefficient of linear thermal expansion in Femtet.

The secant coefficient of thermal expansion is not supported.

 

Set the temperature-independent initial strain on the initial strain tab of the body attribute.

 

Setting Items	Notes
Anisotropy	Selects either Isotropic or Anisotropic.
Temperature Dependency	Selects either No or Yes. When Yes is selected and is clicked, the [Coefficient of Linear Thermal Expansion-Temperature] Table will show up.   In the case of isotropic materials In the case of anisotropic materials   Fill in the table with the temperature and the instantaneous coefficient of linear thermal expansion.   Click the Graph button. The graph for the nonlinearity based on the entered data will show up. At least 2 pairs of data are required for the graphing.
Coefficient of Linear Thermal Expansion	Sets for the material of isotropic and not temperature-dependent.
Vector of Coefficient of Linear Thermal Expansion	Sets for the material of anisotropic and not temperature-dependent. The direction of the material is defined on the Direction tab.