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Material Density in Features Defined in the Material Frame
In a model the features defined in the material frame with an input field for the density expect the density in the material frame, defined for the reference geometry. Hence this density is constant in most cases. A non constant density in the material frame means that there is addition or removal of matter.
As a consequence, when the material is defined from a material library and is temperature dependent, a constant reference temperature, the volume reference temperature, is used for the definition of the density in the Material Contents table.
The volume reference temperature defines the density in the reference geometry that should match with the geometry in the material frame. It is a model input of all the features defined in the material frame with an input field for the density. Following Table 3-5, Table 3-6, and Table 3-7, this concerns the following features: Solid, Porous Medium, Biological Tissue, Building Material, Shape Memory Alloy, Thin Layer (Heat Transfer Interface) and Solid (Heat Transfer in Shells Interface), Fracture (Heat Transfer Interface) and Porous Medium (Heat Transfer in Shells Interface), and Thin Rod.