Description
Base class for all finite elements, that can be used in the ChMesh physics item.
#include <ChElementBase.h>
Public Member Functions | |
virtual int | GetNnodes ()=0 |
Gets the number of nodes used by this element. | |
virtual int | GetNdofs ()=0 |
Gets the number of coordinates in the field used by the referenced nodes. More... | |
virtual int | GetNodeNdofs (int n)=0 |
Get the number of coordinates from the n-th node that are used by this element. More... | |
virtual std::shared_ptr< ChNodeFEAbase > | GetNodeN (int n)=0 |
Access the nth node. | |
virtual void | GetStateBlock (ChVectorDynamic<> &mD)=0 |
Fills the D vector with the current field values at the nodes of the element, with proper ordering. More... | |
virtual void | ComputeMmatrixGlobal (ChMatrixRef M)=0 |
Sets M as the mass matrix. More... | |
virtual void | ComputeNodalMass () |
Compute element's nodal masses. | |
virtual void | ComputeKRMmatricesGlobal (ChMatrixRef H, double Kfactor, double Rfactor=0, double Mfactor=0)=0 |
Sets H as the stiffness matrix K, scaled by Kfactor. More... | |
virtual void | ComputeInternalForces (ChVectorDynamic<> &Fi)=0 |
Computes the internal forces (ex. More... | |
virtual void | Update () |
Update: this is called at least at each time step. More... | |
virtual void | EleDoIntegration () |
This is optionally implemented if there is some internal state that requires integration. | |
virtual void | EleIntLoadResidual_F (ChVectorDynamic<> &R, const double c) |
Adds the internal forces (pasted at global nodes offsets) into a global vector R, multiplied by a scaling factor c, as R += forces * c. | |
virtual void | EleIntLoadResidual_Mv (ChVectorDynamic<> &R, const ChVectorDynamic<> &w, const double c) |
Adds the product of element mass M by a vector w (pasted at global nodes offsets) into a global vector R, multiplied by a scaling factor c, as R += M * v * c. | |
virtual void | InjectKRMmatrices (ChSystemDescriptor &mdescriptor)=0 |
Tell to a system descriptor that there are item(s) of type ChKblock in this object (for further passing it to a solver) Basically does nothing, but inherited classes must specialize this. | |
virtual void | KRMmatricesLoad (double Kfactor, double Rfactor, double Mfactor)=0 |
Adds the current stiffness K and damping R and mass M matrices in encapsulated ChKblock item(s), if any. More... | |
virtual void | VariablesFbLoadInternalForces (double factor=1.) |
Adds the internal forces, expressed as nodal forces, into the encapsulated ChVariables, in the 'fb' part: qf+=forces*factor WILL BE DEPRECATED - see EleIntLoadResidual_F. | |
virtual void | VariablesFbIncrementMq () |
Adds M*q (internal masses multiplied current 'qb') to Fb, ex. More... | |
Friends | |
class | ChMesh |
Member Function Documentation
◆ ComputeInternalForces()
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pure virtual |
Computes the internal forces (ex.
the actual position of nodes is not in relaxed reference position) and set values in the Fi vector, with n.rows = n.of dof of element.
Implemented in chrono::fea::ChElementShellReissner4, chrono::fea::ChElementBeamIGA, chrono::fea::ChElementShellBST, chrono::fea::ChElementTetra_4_P, chrono::fea::ChElementShellANCF_8, chrono::fea::ChElementShellANCF, chrono::fea::ChElementBeamANCF, chrono::fea::ChElementBeamEuler, chrono::fea::ChElementHexa_20, chrono::fea::ChElementCableANCF, chrono::fea::ChElementTetra_10, chrono::fea::ChElementHexa_8, chrono::fea::ChElementTetra_4, chrono::fea::ChElementBar, and chrono::fea::ChElementSpring.
◆ ComputeKRMmatricesGlobal()
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pure virtual |
Sets H as the stiffness matrix K, scaled by Kfactor.
Optionally, also superimposes global damping matrix R, scaled by Rfactor, and mass matrix M, scaled by Mfactor. Matrices are expressed in global reference. Corotational elements can take the local Kl & Rl matrices and rotate them.
Implemented in chrono::fea::ChElementShellReissner4, chrono::fea::ChElementShellBST, chrono::fea::ChElementTetra_4_P, chrono::fea::ChElementShellANCF_8, chrono::fea::ChElementBeamIGA, chrono::fea::ChElementShellANCF, chrono::fea::ChElementBeamANCF, chrono::fea::ChElementBeamEuler, chrono::fea::ChElementHexa_20, chrono::fea::ChElementCableANCF, chrono::fea::ChElementTetra_10, chrono::fea::ChElementHexa_8, chrono::fea::ChElementTetra_4, chrono::fea::ChElementBar, and chrono::fea::ChElementSpring.
◆ ComputeMmatrixGlobal()
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pure virtual |
Sets M as the mass matrix.
The matrix is expressed in global reference.
Implemented in chrono::fea::ChElementShellReissner4, chrono::fea::ChElementShellANCF_8, chrono::fea::ChElementShellANCF, chrono::fea::ChElementBeamANCF, chrono::fea::ChElementCableANCF, and chrono::fea::ChElementGeneric.
◆ GetNdofs()
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pure virtual |
Gets the number of coordinates in the field used by the referenced nodes.
This is for example the size (n.of rows/columns) of the local stiffness matrix.
Implemented in chrono::fea::ChElementTetra_4_P, chrono::fea::ChElementShellBST, chrono::fea::ChElementBeamANCF, chrono::fea::ChElementShellANCF_8, chrono::fea::ChElementShellReissner4, chrono::fea::ChElementShellANCF, chrono::fea::ChElementBeamIGA, chrono::fea::ChElementBeamEuler, chrono::fea::ChElementCableANCF, chrono::fea::ChElementBrick, chrono::fea::ChElementBrick_9, chrono::fea::ChElementTetra_4, chrono::fea::ChElementTetra_10, chrono::fea::ChElementBar, chrono::fea::ChElementHexa_8, chrono::fea::ChElementHexa_20, and chrono::fea::ChElementSpring.
◆ GetNodeNdofs()
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pure virtual |
Get the number of coordinates from the n-th node that are used by this element.
Note that this may be different from the value returned by GetNodeN(n)->Get_ndof_w();
Implemented in chrono::fea::ChElementTetra_4_P, chrono::fea::ChElementShellBST, chrono::fea::ChElementBeamANCF, chrono::fea::ChElementShellANCF_8, chrono::fea::ChElementShellReissner4, chrono::fea::ChElementShellANCF, chrono::fea::ChElementBeamIGA, chrono::fea::ChElementBeamEuler, chrono::fea::ChElementCableANCF, chrono::fea::ChElementBrick, chrono::fea::ChElementBrick_9, chrono::fea::ChElementTetra_4, chrono::fea::ChElementTetra_10, chrono::fea::ChElementBar, chrono::fea::ChElementHexa_8, chrono::fea::ChElementHexa_20, and chrono::fea::ChElementSpring.
◆ GetStateBlock()
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pure virtual |
Fills the D vector with the current field values at the nodes of the element, with proper ordering.
If the D vector size is not this->GetNdofs(), it will be resized. For corotational elements, field is assumed in local reference!
Implemented in chrono::fea::ChElementShellANCF_8, chrono::fea::ChElementShellReissner4, chrono::fea::ChElementShellBST, chrono::fea::ChElementTetra_4_P, chrono::fea::ChElementShellANCF, chrono::fea::ChElementBeamANCF, chrono::fea::ChElementBeamIGA, chrono::fea::ChElementBeamEuler, chrono::fea::ChElementCableANCF, chrono::fea::ChElementHexa_20, chrono::fea::ChElementHexa_8, chrono::fea::ChElementTetra_10, chrono::fea::ChElementTetra_4, chrono::fea::ChElementBar, and chrono::fea::ChElementSpring.
◆ KRMmatricesLoad()
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pure virtual |
Adds the current stiffness K and damping R and mass M matrices in encapsulated ChKblock item(s), if any.
The K, R, M matrices are added with scaling values Kfactor, Rfactor, Mfactor.
Implemented in chrono::fea::ChElementGeneric.
◆ Update()
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inlinevirtual |
Update: this is called at least at each time step.
If the element has to keep updated some auxiliary data, such as the rotation matrices for corotational approach, this is the proper place.
Reimplemented in chrono::fea::ChElementShellReissner4, chrono::fea::ChElementShellBST, chrono::fea::ChElementShellANCF_8, chrono::fea::ChElementShellANCF, chrono::fea::ChElementBeamANCF, chrono::fea::ChElementBeamIGA, chrono::fea::ChElementBeamEuler, chrono::fea::ChElementCableANCF, chrono::fea::ChElementHexahedron, and chrono::fea::ChElementTetrahedron.
◆ VariablesFbIncrementMq()
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inlinevirtual |
Adds M*q (internal masses multiplied current 'qb') to Fb, ex.
if qb is initialized with v_old using VariablesQbLoadSpeed, this method can be used in timestepping schemes that do: M*v_new = M*v_old + forces*dt WILL BE DEPRECATED
Reimplemented in chrono::fea::ChElementGeneric.
The documentation for this class was generated from the following file:
- /builds/uwsbel/chrono/src/chrono/fea/ChElementBase.h