Overview of the User’s Guide
The Structural Mechanics Module User’s Guide gets you started with modeling using COMSOL Multiphysics. The information in this guide is specific to this module. Instructions how to use COMSOL in general are included with the COMSOL Multiphysics Reference Manual.
As detailed in the section Where Do I Access the Documentation and Application Libraries?, this information can also be searched from the Help menu in COMSOL Multiphysics.
Modeling with the Structural Mechanics Module
The Structural Mechanics Modeling chapter gives you an insight on how to approach the modeling of various structural mechanics problems.
Structural Mechanics Theory
The Structural Mechanics Theory chapter introduces the general theory on which the physics interfaces in the Structural Mechanics Module are based.
The Solid Mechanics Interface
The Solid Mechanics chapter describes The Solid Mechanics Interface, which is used to model 3D solids, plane strain and plane stress 2D and 1D models, and 2D axisymmetric models.
The Shell and Plate Interfaces
The Shell and Plate chapter describes The Shell and Plate Interfaces, which are used to model thin 3D structures (shell) and out-of-plane loaded plates (plate). The underlying theory is described in Theory for the Shell and Plate Interfaces.
The Beam Interface
The Beam chapter describes The Beam Interface, which contains Euler (Euler–Bernoulli) and Timoshenko beams for modeling slender 3D and 2D structures. Typical examples are frameworks and latticeworks. The underlying theory for the physics interface is described in Theory for the Beam Interface.
The Beam Cross Section Interface
The Beam Cross Section chapter describes The Beam Cross Section Interface, which is used for computing cross section properties for beams. It can also be used for a detailed evaluation of stresses in a beam when the section forces to which it is subjected are known. The first section discusses Using the Beam Cross Section Interface, and the underlying theory is described in Theory for the Beam Cross Section Interface.
The Truss Interface
The Truss chapter describes The Truss Interface, which models slender 3D and 2D structures with components capable to withstand axial forces only. Typical applications are latticeworks, but it can also be used for modeling cables. In the section Modeling with Truss Elements, you will find a discussion about how to set up models using this interface. The underlying theory for the physics interface is described in Theory for the Truss Interface.
The Membrane Interface
The Membrane chapter describes The Membrane Interface, which can be used for modeling prestressed membranes, cladding on solids, and balloons, for example. The underlying theory for the physics interface is also included in Theory for the Membrane Interface.
The Wire Interface
The Wire chapter describes The Wire Interface, which is mainly intended for modeling pretensioned or sagging wires or cables. The underlying theory for the physics interface is also included in Theory for the Wire Interface.
The Pipe Mechanics Interface
The Pipe Mechanics chapter describes The Pipe Mechanics Interface, which is used for studying the stresses and deformations in piping systems. The underlying theory for the physics interface is also included in Theory for the Pipe Mechanics Interface.
The Phase Field in Solids Interface
The Phase Field in Solids chapter describes The Phase Field in Solids Interface, which is used to determine the degradation of material properties in the damaged regions. The underlying theory for the physics interface is also included in Theory for the Phase Field in Solids Interface.
The Transport in Solids Interface
The Transport in Solids chapter describes The Transport in Solids Interface, which can be used to model transport phenomena in solids. The underlying theory for the physics interface is also included in Theory for the Transport in Solids Interface.
The Multiphysics Interfaces
The Multiphysics Interfaces and Couplings chapter describes these physics interfaces found under the Structural Mechanics branch when adding a physics interface:
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The Thermal Stress, Solid Interface combines a Solid Mechanics interface with a Heat Transfer interface. The coupling appears on the domain level, where the temperature from the Heat Transfer interface acts as a thermal load for the Solid Mechanics interface, causing thermal expansion.
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The Thermal Stress, Shell Interface combines a Shell interface with a Heat Transfer in Shells interface. The coupling appears on the boundary level, where the temperature from the Heat Transfer in Shells interface acts as a thermal load for the Shell interface, causing thermal expansion.
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The Thermal Stress, Layered Shell Interface combines a Layered Shell interface with a Heat Transfer in Shells interface. The coupling appears on the boundary level, where the temperature from the Heat Transfer in Shells interface acts as a thermal load for the Layered Shell interface, causing thermal expansion.
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The Thermal Stress, Membrane Interface combines a Membrane interface with a Heat Transfer in Shells interface. The coupling appears on the boundary level, where the temperature from the Heat Transfer in Shells interface acts as a thermal load for the Membrane interface, causing thermal expansion.
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The Joule Heating and Thermal Expansion Interface combines solid mechanics using a thermal linear elastic material with an electromagnetic Joule heating model. This is a multiphysics combination of solid mechanics, electric currents, and heat transfer for modeling of, for example, thermoelectromechanical (TEM) applications.
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The Piezoelectricity, Solid Interface combines a Solid Mechanics interface with an Electrostatics interface. Piezoelectric materials in 3D, 2D plane strain and plane stress, and 2D axial symmetry can be modeled.
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The Piezoelectricity, Layered Shell Interface combines a Layered Shell interface with an Electric Currents in Layered Shells interface. This makes it possible to model piezoelectric effects in thin layered structures.
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The Piezoelectricity, Layered Shell Interface combines a Layered Shell interface with an Electric Currents in Layered Shells interface. This makes it possible to model piezoelectric effects in thin layered structures.
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The Electrostriction Interface combines a Solid Mechanics with an Electrostatics interface. Using this interface, you can solve problems where strains are caused by electrostrictive effects.
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The Ferroelectroelasticity Interface combines a Solid Mechanics with an Electrostatics interface. Using this interface, you can solve problems involving ferroelectric materials, for example within nonlinear piezoelectricity.
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Hygroscopic Swelling combines a Solid Mechanics with a Magnetic Fields interface. Using this interface, you can solve problems in the magnetostrictive field with linear as well as nonlinear material models.
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The Fluid–Solid Interaction Interface combines fluid flow with the Solid Mechanics interface to capture the interaction between the fluid and the solid in a situation where the fluid domain has significant deformation. The solid material exists on domains which are adjacent to the fluid.
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The Fluid–Shell Interaction Interface combines fluid flow with the Shell interface to capture the interaction between the fluid and the solid in a situation where the fluid domain has significant deformation. The shell is modeled on the boundary of the fluid.
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The Fluid–Membrane Interaction Interface combines fluid flow with the Membrane interface to capture the interaction between the fluid and the membrane in a situation where the fluid domain has significant deformation. The membrane is modeled on the boundary of the fluid.
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The Fluid–Solid Interaction, Fixed Geometry Interface combines fluid flow with the Solid Mechanics interface to capture the interaction between the fluid and the solid in a situation where the fluid domain can be considered to be nondeforming. The solid material exists on domains which are adjacent to the fluid.
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The Fluid–Shell Interaction, Fixed Geometry Interface combines fluid flow with the Shell interface to capture the interaction between the fluid and the solid in a situation where the fluid domain can be considered to be nondeforming. The shell is modeled on the boundary of the fluid
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The Fluid–Membrane Interaction, Fixed Geometry Interface combines fluid flow with the Membrane interface to capture the interaction between the fluid and the membrane in a situation where the fluid domain can be considered to be nondeforming. The membrane is modeled on the boundary of the fluid.
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The Fluid–Pipe Interaction, Fixed Geometry Interface combines flow computed using the Pipe Flow interface with structural analysis in the Pipe Mechanics interface. Different types of fluid loads are transferred to the structural analysis.
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The Fluid–Solid Interaction, Conjugate Heat Transfer Interface combines fluid flow with the Solid Mechanics interface and the Heat Transfer in Solids and Fluids interface. It combines fluid-structure interaction modeling with a nonisothermal flow. Heat transfer is considered both in the fluid and in the solid in order to capture thermal expansion effects.
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The Fluid–Solid Interaction, Two-Phase Flow, Phase Field Interface combines two-phase fluid flow with the Solid Mechanics interface to capture the interaction between the fluid and the solid in a situation where the fluid domain has significant deformation. The solid material exists on domains which are adjacent to the fluid.
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The Fluid–Solid Interaction, Two-Phase Flow, Phase Field, Fixed Geometry Interface combines two-phase fluid flow with the Solid Mechanics interface to capture the interaction between the fluid and the solid in a situation where the fluid domain can be considered to be nondeforming. The solid material exists on domains which are adjacent to the fluid.
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The Fluid–Solid Interaction, Viscoelastic Flow Interface combines the Viscoelastic Flow interface with a Deforming Domain feature and the Solid Mechanics interface to capture the interaction between a viscoelastic fluid and solids in a situation where the fluid domain has significant deformation.
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The Fluid–Solid Interaction, Viscoelastic Flow, Fixed Geometry Interface combines the Viscoelastic Flow interface with a Deforming Domain feature and the Solid Mechanics interface to capture the interaction between a viscoelastic fluid and solids in a situation where the fluid domain can be considered to be nondeforming.
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The Solid–Thin-Film Damping Interface combines the Thin-Film Flow interface and the Solid Mechanics interface to model phenomena where a thin-film fluid and a deformable solid affect each other. The fluid can be either a liquid or a gas, with the possibility to include cavitation in liquids.
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The Shell–Thin-Film Damping Interface combines the Thin-Film Flow interface and the Shell interface to model phenomena where a thin-film fluid and a deformable shells affect each other. The fluid can be either a liquid or a gas, with the possibility to include cavitation in liquids.
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The Poroelasticity, Solid Interface combines a transient formulation of Darcy’s law with a quasistatic formulation of Solid Mechanics. The coupling occurs on the domain level, where the pore pressure from the Darcy’s Law interface acts as a load for the Solid Mechanics interface, causing swelling or shrinking. Changes in volumetric strain affect the pore space, acting as a mass source or sink in Darcy’s Law.
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The Poroelasticity, Layered Shell Interface combines the Layered Darcy’s Law formulation with the Layered Shell interface for structural mechanics. This multiphysics interface is only available for 3D simulations and it can be active on boundaries where a layered material is present.
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The Unsaturated Poroelasticity Interface combines a transient formulation of Moisture Transport in Solids with a quasistatic formulation of Solid Mechanics. The coupling occurs on the domain level, where the pore pressure from the Moisture Transport in Solids interface acts as a load for the Solid Mechanics interface, causing swelling or shrinking. Changes in volumetric strain affect the pore space, impacting the transport of moist air and liquid water in the porous solid.
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The Phase-Field Damage Interface combines the Solid Mechanics and Phase Field in Solids interfaces to model the evolution of damage and cracks in deforming solids. The coupling occurs on the domain level, where the driving force for damage depends on the state of deformation in the solid, which governs the evolution of the phase field. In turn, the phase field determines the degradation of the solid properties in the damaged regions.