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MechanicalFemPhysics
The GeMA Mechanical FEM Physics Plugin
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MechanicalFemPhysics
The GeMA Mechanical FEM Physics Plugin
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The Mechanical FEM physics plugin implementation is divided in the following plugin options:
The Mechanical Fem Physic plugin publishes four objects type depending on the nature of the element formulation: Continuum element, Interface element,composite element and Large deformation.
a) Continuum element plugin options
b) Interface element plugin options
c) "Composite element plugin options".
d) "Large deformation plugin options".
The Mechanical Fem Physic plugin requires the model to contain the displacement state variable 'u', which is a vector with size equal to the node coordinate dimension. Both formulation, continuum and interface elements, require the same state variable 'u'.
Example:
The Mechanical Fem Physic plugin uses different materials according to the element formulation adopted: continnum, interface, Composite, and large deformation.
a) Continuum material reference.
b) Interface material reference.
When defining plugin object of Mechanical fem Physic, the following fields are available for usage during the definition:
| Attribute | Description | Type | Required | Def. Value |
|---|---|---|---|---|
| id | The physics name. | String | Yes | - |
| Example: id = 'myPhysicsName' | ||||
| typeName | Physics defines the plugin name according to the type name such as 'planeStress','planeStrain', etc. | String | Yes | - |
| Example: typeName = 'MechanicalFemPhysics.3D' | ||||
| type | Type of physics object. Should be equal to 'fem'. | String | Yes | - |
| Required value: type= 'fem' | ||||
| ruleSet | Integration rule set selected for simulation elements. | String | No | Empty |
| Example: ruleSet = 1 | ||||
| mesh | The mesh name. | String | Yes | - |
| Example: mesh = 'myMeshName' | ||||
| boundaryConditions | Table filled with the names of the boundary conditions associated with this physics. | String table | Yes | - |
| Example: boundaryConditions = {'myBc1', 'myBc2', 'myBc3'} | ||||
| materials | Table filled with the names of the materials associated with this analysis. | String table | Yes | - |
| Example: materials = {'elastic', 'vonMises', 'elasticInterface'} | ||||
| enabledGravity | Boolean value to enable or disable the gravity. | String table | No | - |
| Example: enabledGravity = 'true' | ||||
| enabledBodyForce | Boolean value to enable or disable the Body Force. | String table | No | - |
| Example: enabledBodyForce = 'true' | ||||
| externalLoads | For staggered solution, either in a one way or in a two way schema, results from hydraulic physics can be accounted as external load. The mechanical Fem physics supports pore pressure "P" as external load. | Table | No | nil |
Example: externalLoads = { pressureLoad = "P" } | ||||
| externalLoadRegions | Sometimes, the provided external loads should not be applied to the whole spatial domain, but instead to a mesh sub-domain. Like elementGorups, this attribute allows for specifying the set of elements over which an external load will be applied. | Table | No | nil |
Example: externalLoadRegions = { pressureLoad = { "cellGroup1", "cellGroup3", disjoint = true } } | ||||
Like other Fem physics, stateVar, property and attribute renaming fields are supported. Likewise, restricting the physics application domain to a set of cell groups, setting the desired integration rule and unit system remapping are also available. Those common optional fields are detailed at the GeMA Common Fem Porocess.
Example for problems using Continuum Elements:
Example for problems using Interface Elements:
The plugin of Mechanical Fem physics supports the followin Boundary conditions.
The Mechanical Fem Physic sets a fixed displacement and prescribed value.
Example:
The Mechanical Fem Physic sets node concentrated forces as detailed below.
Example:
The pressure is applied to the model by defining a pressure value on the edge (2D) or face (3D). Pressure is definied in kPa, Positive signal means that the pressure is entering into the model.
Example:
The Mechanical Fem Physic plugin supports different elements according to the element formulation adopted: continnum, interface, Composite, and large deformation.
a) Continuum supported element
b) Interface supported element
c) "Composite element plugin options".
d) "Large deformation plugin options".
The Mechanical Fem physics uses internally the international system of units for its calculations, as can be seen above by the default units for properties and attributes. The whole unit system can be replaced through the unitSystem physics attribute, as described at the gemaFemProcessCommonFemPhysicsOptions page.
When making the substitution, the units on the follwoing table should be replaced by the desired units, forming a coherent unit system. The unit system of the material should be also replaced.
1.8.15