You are viewing the documentation for an older COMSOL version. The latest version is available here.
Linear Elastic Material
The Linear Elastic Material node adds the equations for a linear elastic beam 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:
•
Thermal Expansion (for Materials)
•
Hygroscopic Swelling
•
Initial Stress and Strain
•
External Stress
•
Safety
•
Damping
Linear Elastic Material
Define the linear elastic material properties.
Specification of Elastic Properties for Isotropic Materials
From the Specify list, select a pair of elastic properties for an isotropic material. Select:
•
Young’s modulus and Poisson’s ratio to specify Young’s modulus (elastic modulus) E and Poisson’s ratio ν. Poisson’s ratio is used for computing the torsional stiffness, and is thus important only for 3D beams.
•
Young’s modulus and shear modulus to specify Young’s modulus (elastic modulus) E and the shear modulus G. The shear modulus is used for computing the torsional stiffness, and is thus important only for 3D beams.
•
Bulk modulus and shear modulus to specify the bulk modulus K and the shear modulus G.
•
Lamé parameters to specify the Lamé parameters λ and μ.
•
Pressure-wave and shear-wave speeds to specify the pressure-wave speed (longitudinal wave speed) cp and the shear-wave speed (transverse wave speed) cs.
This is the wave speed for a solid continuum. In a truss or beam element, the actual speed with which a longitudinal wave travels is lower than the value given. When using this type of input the density must also be given.
For each pair of properties, select from the applicable list to use the value From material or enter a User defined value or expression.
Each of these pairs define the elastic properties, and it is possible to convert from one set of properties to another.
Density
Define the Density ρ of the material. Select From material to take the value from the material or User defined to enter a value for the density.
The density is needed for dynamic analysis or when the elastic data is given in terms of wave speed. It is also used when computing mass forces for gravitational or rotating frame loads, and when computing mass properties (Computing Mass Properties).
Thermally Loaded Beam: Application Library path Structural_Mechanics_Module/Verification_Examples/thermally_loaded_beam
Location in User Interface
Context Menus
Beam>Material Models>Linear Elastic Material
Ribbon
Physics tab with Beam selected:
Edges>Material Models>Linear Elastic Material (3D)
Boundaries>Material Models>Linear Elastic Material (2D)