Nodal Gravity

Computes the gravitational force for a given nodal mass.

Description

This NodalKernel computes the gravitational force proportional to nodal mass in the coordinate direction corresponding to the assigned variable. A constant gravitational acceleration can be provided using gravity_value parameter and an acceleration varying in space and time can be provided using the function parameter. A constant mass for all the nodes in the given boundary can be provided using the mass parameter. Otherwise, a CSV file containing nodal positions and the corresponding nodal masses can also be provided using the nodal_mass_file parameter.

For example, the below csv file has two rows with 4 columns. The first three columns correspond to the nodal positions in the global coordinate system and the last column corresponds to the nodal mass. Each row contains position and mass information for one node.

0.0, 0.0, 0.0, 2.0
4.0, 0.0, 0.0, 0.01899772
(modules/solid_mechanics/test/tests/beam/dynamic/nodal_mass.csv)

Input Parameters

  • variableThe name of the variable that this residual object operates on

    C++ Type:NonlinearVariableName

    Controllable:No

    Description:The name of the variable that this residual object operates on

Required Parameters

  • alpha0Alpha parameter for mass dependent numerical damping induced by HHT time integration scheme

    Default:0

    C++ Type:double

    Controllable:No

    Description:Alpha parameter for mass dependent numerical damping induced by HHT time integration scheme

  • blockThe list of blocks (ids or names) that this object will be applied

    C++ Type:std::vector<SubdomainName>

    Controllable:No

    Description:The list of blocks (ids or names) that this object will be applied

  • boundaryThe list of boundaries (ids or names) from the mesh where this object applies

    C++ Type:std::vector<BoundaryName>

    Controllable:No

    Description:The list of boundaries (ids or names) from the mesh where this object applies

  • function1A function that describes the gravitational force

    Default:1

    C++ Type:FunctionName

    Controllable:No

    Description:A function that describes the gravitational force

  • gravity_value0Acceleration due to gravity.

    Default:0

    C++ Type:double

    Controllable:No

    Description:Acceleration due to gravity.

  • massMass associated with the node

    C++ Type:double

    Controllable:No

    Description:Mass associated with the node

  • nodal_mass_fileThe file containing the nodal positions and the corresponding nodal masses.

    C++ Type:FileName

    Controllable:No

    Description:The file containing the nodal positions and the corresponding nodal masses.

Optional Parameters

  • absolute_value_vector_tagsThe tags for the vectors this residual object should fill with the absolute value of the residual contribution

    C++ Type:std::vector<TagName>

    Controllable:No

    Description:The tags for the vectors this residual object should fill with the absolute value of the residual contribution

  • extra_matrix_tagsThe extra tags for the matrices this Kernel should fill

    C++ Type:std::vector<TagName>

    Controllable:No

    Description:The extra tags for the matrices this Kernel should fill

  • extra_vector_tagsThe extra tags for the vectors this Kernel should fill

    C++ Type:std::vector<TagName>

    Controllable:No

    Description:The extra tags for the vectors this Kernel should fill

  • matrix_tagssystemThe tag for the matrices this Kernel should fill

    Default:system

    C++ Type:MultiMooseEnum

    Options:nontime, system

    Controllable:No

    Description:The tag for the matrices this Kernel should fill

  • vector_tagsnontimeThe tag for the vectors this Kernel should fill

    Default:nontime

    C++ Type:MultiMooseEnum

    Options:nontime, time

    Controllable:No

    Description:The tag for the vectors this Kernel should fill

Tagging Parameters

  • control_tagsAdds user-defined labels for accessing object parameters via control logic.

    C++ Type:std::vector<std::string>

    Controllable:No

    Description:Adds user-defined labels for accessing object parameters via control logic.

  • diag_save_inThe name of auxiliary variables to save this BC's diagonal jacobian contributions to. Everything about that variable must match everything about this variable (the type, what blocks it's on, etc.)

    C++ Type:std::vector<AuxVariableName>

    Controllable:No

    Description:The name of auxiliary variables to save this BC's diagonal jacobian contributions to. Everything about that variable must match everything about this variable (the type, what blocks it's on, etc.)

  • enableTrueSet the enabled status of the MooseObject.

    Default:True

    C++ Type:bool

    Controllable:Yes

    Description:Set the enabled status of the MooseObject.

  • implicitTrueDetermines whether this object is calculated using an implicit or explicit form

    Default:True

    C++ Type:bool

    Controllable:No

    Description:Determines whether this object is calculated using an implicit or explicit form

  • save_inThe name of auxiliary variables to save this BC's residual contributions to. Everything about that variable must match everything about this variable (the type, what blocks it's on, etc.)

    C++ Type:std::vector<AuxVariableName>

    Controllable:No

    Description:The name of auxiliary variables to save this BC's residual contributions to. Everything about that variable must match everything about this variable (the type, what blocks it's on, etc.)

  • seed0The seed for the master random number generator

    Default:0

    C++ Type:unsigned int

    Controllable:No

    Description:The seed for the master random number generator

  • use_displaced_meshFalseWhether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

    Default:False

    C++ Type:bool

    Controllable:No

    Description:Whether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

Advanced Parameters

Input Files