The Piezoresistivity, Layered Shell Interface
This physics interface requires a Composite Material Module license. For theory and physics interface feature descriptions relating to the Layered Shell interface, see the Structural Mechanics Module User’s Guide.
The Piezoresistivity, Layered Shell interface () combines structural layered shells and electric currents in shells together with the constitutive relationships required to model the piezoresistive effects. The piezoresistive coupling can be formulated using either the piezoresistance or elastoresistance form.
When a predefined Piezoresistivity, Layered Shell interface is added from the Structural Mechanics branch () of the Model Wizard or from Add Physics windows, Layered Shell and Electric Currents in Layered Shells interfaces are added to the Model Builder.
In addition, the Multiphysics node is added, which automatically includes the multiphysics coupling feature Piezoresistivity, Layered.
The participating Electric Currents in Layered Shells interface will include by default a Piezoresistive Shell feature. (Such a feature can be also added manually to the corresponding interface.) You this feature to select those boundaries and layers, where the material is supposed to experience piezoresistive coupling. All piezoresistivity properties are entered in this feature. Note that the Piezoresistivity, Layered multiphysics coupling node can be active only on the selection, where Piezoresistive Shell is active. When used without the coupling feature, the Piezoresistive Shell node acts as an ordinary Conductive Shell feature with its material data input limited to the electric conductivity only.
All structural and electric functionality for modeling is also accessible to include surrounding elastic solids or air domains. For example, add any material model for other solid domains, a conductive or dielectric model, or a combination of these. Note that in order to model a nonsolid conductive or dielectric domain, such as air, you need to remove such domains from the domain selection for the entire Layered Shell interface. This is because all material models under that interface represent solid materials (with the Linear Elastic Material node always being present and active in all domains where it is not explicitly overridden by any other material model).
On the Constituent Physics Interfaces
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The Layered Shell interface is described in The Layered Shell Interface.
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The Electric Currents in Layered Shells interface is described in The Electric Currents, Layered Shell Interface in the AC/DC Module User’s Guide.
Settings for Physics Interfaces and Coupling Features
When physics interfaces are added using the predefined couplings, for example Piezoresistivity, Layered Shell, specific settings are included with the physics interfaces and the coupling features.
However, if physics interfaces are added one at a time, followed by the coupling features, these modified settings are not automatically included.
For example, if both Layered Shell and Electric Currents in Layered Shells interfaces are added, COMSOL Multiphysics adds an empty Multiphysics node. You can add the available coupling feature Piezoresistivity, Layered but the modified settings are not included.
Coupling features are available from the context menu (right-click the Multiphysics node) or from the Physics toolbar, Multiphysics Couplings menu.
Physics Interfaces and Coupling Features
Use the online help in COMSOL Multiphysics to locate and search all the documentation. All these links also work directly in COMSOL Multiphysics when using the Help system.