- direction_vectorThe direction vector of the axis of rotation about which the calculated torque is calculated
C++ Type:libMesh::VectorValue<double>
Controllable:No
Description:The direction vector of the axis of rotation about which the calculated torque is calculated
- reaction_force_variablesThe reaction variables
C++ Type:std::vector<AuxVariableName>
Controllable:No
Description:The reaction variables
Torque Reaction
TorqueReaction calculates the torque in 2D and 3Dabout a user-specified axis of rotation centeredat a user-specified origin.
Description
The postprocessor TorqueReaction calculates the applied torque from the reaction forces, coupled as AuxVariables, about a user specified axis of rotation.
TorqueReaction takes a scalar approach to calculating the sum of the acting torques by projecting both the reaction force vector and the position vector (the coordinates of the node upon which the force is applied) onto the axis of rotation and applying the Pythagorean theorem, as in a statics course. This scalar approach allows the postprocessor to accept any axis of rotation direction.
The torque from the reaction forces is calculated, as shown in Eq. (1) relative to the user specified axis of rotation origin and direction. (1) where is the applied reaction force vector, is the current node position, is the origin of the axis of rotation, and is the direction vector of the axis of rotation. The component of the torque acting along the user specified axis of rotation vector, is calcuated as Eq. (2): (2) where is the torque vector calculated in Eq. (1) and is the axis of rotation direction vector.
Example Input File Syntax
[./torque]
type = TorqueReaction
boundary = right
reaction_force_variables = 'saved_x saved_y'
direction_vector = '0. 0. 1.'
[../]
A list of the AuxVariables which save the reaction forces must be provided to the TorqueReaction block.
[./saved_x]
[../]
[./saved_y]
[../]
The reaction force AuxVariables must also be computed using the tagging system to save the reactions to a separate vector in the stress divergence kernel, which is handled in this case using the extra_vector_tags parameter in the Master action:
[Modules/TensorMechanics/Master]
[Modules/TensorMechanics/Master]
[Modules/TensorMechanics/Master]
[master]
strain = SMALL
generate_output = 'stress_xx stress_yy'
add_variables = true
extra_vector_tags = 'ref'
[]
[]
[]
[]
The TagVectorAux AuxKernel is used to extract the saved components of the reaction vector from a tagged vector and put them in an AuxVariable. This shows how the component of this is extracted, and the others are handled in a similar manner:
[saved_x]
type = TagVectorAux
vector_tag = 'ref'
v = 'disp_x'
variable = 'saved_x'
[]
Input Parameters
- axis_origin0 0 0Origin of the axis of rotation used to calculate the torque
Default:0 0 0
C++ Type:libMesh::VectorValue<double>
Controllable:No
Description:Origin of the axis of rotation used to calculate the torque
- 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
- execute_onTIMESTEP_ENDThe list of flag(s) indicating when this object should be executed, the available options include NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, MULTIAPP_FIXED_POINT_END, MULTIAPP_FIXED_POINT_BEGIN, FINAL, CUSTOM, ALWAYS.
Default:TIMESTEP_END
C++ Type:ExecFlagEnum
Controllable:No
Description:The list of flag(s) indicating when this object should be executed, the available options include NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, MULTIAPP_FIXED_POINT_END, MULTIAPP_FIXED_POINT_BEGIN, FINAL, CUSTOM, ALWAYS.
- unique_node_executeFalseWhen false (default), block restricted objects will have the execute method called multiple times on a single node if the node lies on a interface between two subdomains.
Default:False
C++ Type:bool
Controllable:No
Description:When false (default), block restricted objects will have the execute method called multiple times on a single node if the node lies on a interface between two subdomains.
Optional Parameters
- allow_duplicate_execution_on_initialFalseIn the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).
Default:False
C++ Type:bool
Controllable:No
Description:In the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).
- 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.
- enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Controllable:Yes
Description:Set the enabled status of the MooseObject.
- execution_order_group0Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group.
Default:0
C++ Type:int
Controllable:No
Description:Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group.
- force_postauxFalseForces the UserObject to be executed in POSTAUX
Default:False
C++ Type:bool
Controllable:No
Description:Forces the UserObject to be executed in POSTAUX
- force_preauxFalseForces the UserObject to be executed in PREAUX
Default:False
C++ Type:bool
Controllable:No
Description:Forces the UserObject to be executed in PREAUX
- force_preicFalseForces the UserObject to be executed in PREIC during initial setup
Default:False
C++ Type:bool
Controllable:No
Description:Forces the UserObject to be executed in PREIC during initial setup
- outputsVector of output names where you would like to restrict the output of variables(s) associated with this object
C++ Type:std::vector<OutputName>
Controllable:No
Description:Vector of output names where you would like to restrict the output of variables(s) associated with this object
- 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_meshTrueWhether 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:True
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.