Description
Base class for all constitutive models of sections of Euler beams.
To be used with ChElementBeamEuler. For practical purposes, either you use the concrete inherited classes like ChBeamSectionEulerSimple, ChBeamSectionEulerAdvanced etc., or you inherit your class from this.
#include <ChBeamSectionEuler.h>
Public Member Functions | |
| virtual double | GetAxialRigidity () const =0 |
| Gets the axial rigidity, usually A*E, but might be ad hoc. | |
| virtual double | GetXtorsionRigidity () const =0 |
| Gets the torsion rigidity, for torsion about X axis at elastic center, usually J*G, but might be ad hoc. | |
| virtual double | GetYbendingRigidity () const =0 |
| Gets the bending rigidity, for bending about Y axis at elastic center, usually Iyy*E, but might be ad hoc. | |
| virtual double | GetZbendingRigidity () const =0 |
| Gets the bending rigidity, for bending about Z axis at elastic center, usually Izz*E, but might be ad hoc. | |
| virtual double | GetSectionRotation () const =0 |
| Set the rotation of the Y Z section axes for which the YbendingRigidity and ZbendingRigidity are defined. | |
| virtual double | GetCentroidY () const =0 |
| Gets the Y position of the elastic center respect to centerline. | |
| virtual double | GetCentroidZ () const =0 |
| Gets the Z position of the elastic center respect to centerline. | |
| virtual double | GetShearCenterY () const =0 |
| Gets the Y position of the shear center respect to centerline. | |
| virtual double | GetShearCenterZ () const =0 |
| Gets the Z position of the shear center respect to centerline. | |
| virtual double | GetMassPerUnitLength () const =0 |
| Get mass per unit length, ex.SI units [kg/m]. | |
| virtual double | GetInertiaJxxPerUnitLength () const =0 |
| Get the Jxx component of the inertia per unit length (polar inertia) in the Y Z unrotated reference frame of the section at centerline. More... | |
| virtual void | ComputeInertiaMatrix (ChMatrixNM< double, 6, 6 > &M)=0 |
| Compute the 6x6 sectional inertia matrix, as in {x_momentum,w_momentum}=[Mm]{xvel,wvel} The matrix is computed in the material reference (i.e. More... | |
| virtual void | ComputeQuadraticTerms (ChVector<> &mF, ChVector<> &mT, const ChVector<> &mW)=0 |
| Compute the values of inertial force & torque depending on quadratic velocity terms, that is the gyroscopic torque (null for Euler beam as point-like mass section, might be nonzero if adding Rayleigh beam theory) and the centrifugal term (if any). More... | |
| void | SetArtificialJyyJzzFactor (double mf) |
| The Euler beam model has no rotational inertia per each section, assuming mass is concentrated on the centerline. More... | |
| double | GetArtificialJyyJzzFactor () |
| void | SetBeamRaleyghDamping (double mr) |
| Set the Rayleigh damping ratio r (as in: R = r * K ), to do: also mass-proportional term. | |
| double | GetBeamRaleyghDamping () |
 Public Member Functions inherited from chrono::fea::ChBeamSection | |
| void | SetDrawShape (std::shared_ptr< ChBeamSectionShape > mshape) |
| Set the graphical representation for this section. More... | |
| std::shared_ptr< ChBeamSectionShape > | GetDrawShape () const |
| Get the drawing shape of this section (i.e.a 2D profile used for drawing 3D tesselation and visualization) By default a thin square section, use SetDrawShape() to change it. | |
| void | SetDrawThickness (double thickness_y, double thickness_z) |
| Shortcut: adds a ChBeamSectionShapeRectangular for visualization as a centered rectangular beam, and sets its width/height. More... | |
| void | SetDrawCircularRadius (double draw_rad) |
| Shortcut: adds a ChBeamSectionShapeCircular for visualization as a centered circular beam, and sets its radius. More... | |
| void | SetCircular (bool ic) |
| OBSOLETE only for backward compability More... | |
Protected Attributes | |
| double | JzzJyy_factor |
Member Function Documentation
◆ ComputeInertiaMatrix()
|
pure virtual |
Compute the 6x6 sectional inertia matrix, as in {x_momentum,w_momentum}=[Mm]{xvel,wvel} The matrix is computed in the material reference (i.e.
it is the sectional mass matrix)
- Parameters
-
M 6x6 sectional mass matrix values here
Implemented in chrono::fea::ChBeamSectionRayleighAdvancedGeneric, chrono::fea::ChBeamSectionRayleighSimple, chrono::fea::ChBeamSectionEulerAdvancedGeneric, and chrono::fea::ChBeamSectionEulerSimple.
◆ ComputeQuadraticTerms()
|
pure virtual |
Compute the values of inertial force & torque depending on quadratic velocity terms, that is the gyroscopic torque (null for Euler beam as point-like mass section, might be nonzero if adding Rayleigh beam theory) and the centrifugal term (if any).
All terms expressed in the material reference, ie. the reference in the centerline of the section.
- Parameters
-
mF centrifugal term (if any) returned here mT gyroscopic term returned here mW current angular velocity of section, in material frame
Implemented in chrono::fea::ChBeamSectionEulerAdvancedGeneric, and chrono::fea::ChBeamSectionEulerSimple.
◆ GetInertiaJxxPerUnitLength()
|
pure virtual |
Get the Jxx component of the inertia per unit length (polar inertia) in the Y Z unrotated reference frame of the section at centerline.
Note: it automatically follows Jxx=Jyy+Jzz for the polar theorem. Also, Jxx=density*Ixx if constant density.
Implemented in chrono::fea::ChBeamSectionEulerAdvancedGeneric, and chrono::fea::ChBeamSectionEulerSimple.
◆ SetArtificialJyyJzzFactor()
|
inline |
The Euler beam model has no rotational inertia per each section, assuming mass is concentrated on the centerline.
However this creates a singular mass matrix, that might end in problems when doing modal analysis etc. A solution is to force Jyy and Jzz inertials per unit lengths to be a percent of the mass per unit length. By default it is 1/500. Use this function to set such factor. You can also turn it to zero. Note that the effect becomes negligible anyway for finer meshing.
The documentation for this class was generated from the following file:
- /builds/uwsbel/chrono/src/chrono/fea/ChBeamSectionEuler.h
