The Linear Elastic Material node adds the equations for a linear elastic solid and an interface for defining the elastic material properties.
By adding the following subnodes to the Linear Elastic Material node you can incorporate many other effects:
The Global coordinate system is selected by default. The
Coordinate system list contains all applicable coordinate systems in the component. The coordinate system is used for interpreting directions of orthotropic and anisotropic material data and when stresses or strains are presented in a local system. The coordinate system must have orthonormal coordinate axes, and be defined in the material frame. Many of the possible subnodes inherit the coordinate system settings.
Define the Solid model and the linear elastic material properties.
Note: The Orthotropic and
Anisotropic options are only available with certain COMSOL products (see
https://www.comsol.com/products/specifications/)
The default Density ρ uses values
From material. For
User defined enter another value or expression.
If any material in the model has a temperature dependent mass density, and From material is selected, the
Volume reference temperature list will appear in the
Model Input section. As a default, the value of
Tref is obtained from a
Common model input. You can also select
User defined to enter a value or expression for the reference temperature locally.
For an Isotropic Solid model, from the
Specify list select a pair of elastic properties for an isotropic material —
Young’s modulus and Poisson’s ratio,
Young’s modulus and shear modulus,
Bulk modulus and shear modulus,
Lamé parameters, or
Pressure-wave and shear-wave speeds. For each pair of properties, select from the applicable list to use the value
From material or enter a
User defined value or expression.
When Orthotropic is selected from the
Solid model list, the material properties vary in orthogonal directions only. The
Material data ordering can be specified in either
Standard or
Voigt notation. When
User defined is selected in 3D, enter three values in the fields for
Young’s modulus E,
Poisson’s ratio ν, and the
Shear modulus G. This defines the relationship between engineering shear strain and shear stress. It is applicable only to an
orthotropic material and follows the equation
When Anisotropic is selected from the
Solid model list, the material properties vary in all directions, and the stiffness comes from the symmetric
Elasticity matrix,
D. The
Material data ordering can be specified in either
Standard or
Voigt notation. When
User defined is selected, a 6-by-6 symmetric matrix is displayed.
If a study step is geometrically nonlinear, the default behavior is to use a large strain formulation in all domains. Select the Geometrically linear formulation check box to always use a small strain formulation, irrespective of the setting in the study step.
Select the Calculate dissipated energy check box as needed to compute the energy dissipated by for example creep, plasticity, viscoplasticity, viscoelasticity, or damping.
If Pressure formulation is used, select the discretization for the
Auxiliary pressure —
Automatic,
Discontinuous Lagrange,
Continuous,
Linear or
Constant. If
Strain formulation is used, select the discretization for the
Auxiliary volumetric strain —
Automatic,
Discontinuous Lagrange,
Continuous,
Linear or
Constant.
Select the Reduced integration check box to reduce the integration points for the weak contribution of the feature. Select a method for
Hourglass stabilization —
Automatic,
Manual, or
None to use in combination with the reduced integration scheme. The default
Automatic stabilization technique is based on the shape function and shape order of the displacement field.
When Shear stabilization is selected, enter a stabilization shear modulus,
Gstb. The value should be in the order of magnitude of the equivalent shear modulus.
When Volumetric stabilization is selected, enter a stabilization bulk modulus,
Kstb. The value should be in the order of magnitude of the equivalent bulk modulus.