netdem::LinearSpring Class Reference

Contact model that uses linear spring elements to evaluate contact forces and moments. More...

#include <model_linear_spring.hpp>

Inheritance diagram for netdem::LinearSpring:

Public Member Functions
	LinearSpring ()
	Default constructor for LinearSpring.
	LinearSpring (double kn, double kt, double mu, double beta)
	Constructor for LinearSpring.
nlohmann::json	PackJson () override
	Packs the contact model properties into a JSON object.
void	InitFromJson (nlohmann::json const &js) override
	Initializes the contact model from a JSON object.
void	SetProperty (nlohmann::json const &js) override
	Sets the contact model properties.
void	SetProperty (std::string const &name, double value) override
	Sets a specific contact model property.
ContactModel *	Clone () const override
	Creates a copy of this contact model.
void	EvaluateForces (ContactForces *const cnt_forces, CollisionGeometries &cnt_geoms, ContactPP *const cnt, double dt) const override
	Evaluates the forces and moments between two particles using linear spring elements.
void	EvaluateForces (ContactForces *const cnt_forces, CollisionGeometries &cnt_geoms, ContactPW *const cnt, double dt) const override
	Evaluates the forces and moments between a particle and a wall using linear spring elements.
void	Print () const override
	Prints the contact model properties.
Public Member Functions inherited from netdem::ContactModel
virtual void	EvaluateForces (ContactForces *const cnt_forces, BondGeometries &cnt_geoms, ContactPP *const cnt, double dt) const
	Calculate the contact forces and moments due to this model.
virtual void	EvaluateForces (ContactForces *const cnt_forces, BondGeometries &cnt_geoms, ContactPW *const cnt, double dt) const
	Calculate the contact forces and moments due to this model.
virtual	~ContactModel ()

Public Attributes
double	kn {2e6}
	< Parameters used to calculate contact forces.
double	kt {1e6}
double	beta {0.7}
double	mu {0.5}
Public Attributes inherited from netdem::ContactModel
int	id {0}
std::string	label {"default"}
int	model_type {0}
std::string	model_name {"contact_model"}

Additional Inherited Members
Public Types inherited from netdem::ContactModel
enum	Type {   none , linear_spring , hertz_mindlin , volume_based ,   parallel_bond }

Detailed Description

Contact model that uses linear spring elements to evaluate contact forces and moments.

The linear spring contact model calculates the contact force based on the contact deformation, which is proportional to the normal displacement between two particles. The tangential force is calculated based on the Coulomb's friction law.

Examples

00_contact_test_sphere.cpp, 00_hertz_contact.cpp, 00_nut_in_bolt.cpp, 01_contact_test_trimesh.cpp, 02_energy_test.cpp, 03_friction_test_sphere.cpp, 04_friction_test_trimesh.cpp, 0_geometric_solver.cpp, 0_plane_case.cpp, 10_contact_test_sphere.cpp, 11_contact_test_trimesh.cpp, 1_gjk_solver.cpp, 1_membrane_case.cpp, 1_test_triaxial_comp.cpp, 21_test_dataset_ellipsoid_plane.cpp, 26_test_ann_vs_geom_ellipsoid_plane.cpp, 2_sdf_solver.cpp, 31_test_dataset_ellipsoid.cpp, 36_test_ann_vs_geom_ellipsoid.cpp, 37_test_ann_vs_geom_ellipsoid.cpp, 3_hybrid_solver.cpp, 81_golf_ball_impact.cpp, 81_voronoi_packing.cpp, 90_packing_demo.cpp, 90_random_packing.cpp, 91_packing_ellipsoid.cpp, 91_triaixal_comp_trimesh.cpp, 92_angle_repose_trimesh.cpp, 92_nut_in_bolt.cpp, 93_triaixal_comp_trimesh.cpp, 94_angle_repose_trimesh.cpp, 96_random_packing_ellipsoid.cpp, angle_repose_main.cpp, blade_mixing_main.cpp, landslide_main.cpp, and odemetric_comp_main.cpp.

Constructor & Destructor Documentation

LinearSpring() [1/2]

netdem::LinearSpring::LinearSpring

(

)

Default constructor for LinearSpring.

LinearSpring() [2/2]

netdem::LinearSpring::LinearSpring	(	double	kn,
		double	kt,
		double	mu,
		double	beta )

Constructor for LinearSpring.

Parameters

kn	Normal stiffness parameter used to calculate contact forces.
kt	Tangential stiffness parameter used to calculate contact forces.
mu	Coefficient of friction used to calculate contact forces.
beta	Coefficient of restitution used to calculate contact forces.

Member Function Documentation

Clone()

ContactModel * netdem::LinearSpring::Clone ( ) const

overridevirtual

Creates a copy of this contact model.

Returns

A new instance of the contact model.

Reimplemented from netdem::ContactModel.

EvaluateForces() [1/2]

void netdem::LinearSpring::EvaluateForces ( ContactForces *const cnt_forces, CollisionGeometries & cnt_geoms, ContactPP *const cnt, double dt ) const

overridevirtual

Evaluates the forces and moments between two particles using linear spring elements.

Parameters

cnt_forces	The contact forces data structure to store the results.
cnt_geoms	The collision geometries data structure containing the contact information.
cnt	The contact point between the two particles.
dt	The simulation timestep.

Reimplemented from netdem::ContactModel.

EvaluateForces() [2/2]

void netdem::LinearSpring::EvaluateForces ( ContactForces *const cnt_forces, CollisionGeometries & cnt_geoms, ContactPW *const cnt, double dt ) const

overridevirtual

Evaluates the forces and moments between a particle and a wall using linear spring elements.

Parameters

cnt_forces	The contact forces data structure to store the results.
cnt_geoms	The collision geometries data structure containing the contact information.
cnt	The contact point between the particle and the wall.
dt	The simulation timestep.

Reimplemented from netdem::ContactModel.

InitFromJson()

void netdem::LinearSpring::InitFromJson ( nlohmann::json const & js )

overridevirtual

Initializes the contact model from a JSON object.

Parameters

js	A JSON object containing the contact model properties.

Reimplemented from netdem::ContactModel.

PackJson()

nlohmann::json netdem::LinearSpring::PackJson ( )

overridevirtual

Packs the contact model properties into a JSON object.

Returns

A JSON object containing the contact model properties.

Reimplemented from netdem::ContactModel.

Print()

void netdem::LinearSpring::Print ( ) const

overridevirtual

Prints the contact model properties.

Reimplemented from netdem::ContactModel.

SetProperty() [1/2]

void netdem::LinearSpring::SetProperty ( nlohmann::json const & js )

overridevirtual

Sets the contact model properties.

Parameters

js	A JSON object containing the contact model properties.

Reimplemented from netdem::ContactModel.

SetProperty() [2/2]

void netdem::LinearSpring::SetProperty ( std::string const & name, double value )

overridevirtual

Sets a specific contact model property.

Parameters

name	The name of the property to set.
value	The value to set the property to.

Reimplemented from netdem::ContactModel.

Member Data Documentation

beta

double netdem::LinearSpring::beta {0.7}

kn

double netdem::LinearSpring::kn {2e6}

< Parameters used to calculate contact forces.

kt

double netdem::LinearSpring::kt {1e6}

mu

double netdem::LinearSpring::mu {0.5}

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The documentation for this class was generated from the following files:

• /Users/lzhshou/Documents/Research/myProjects/apaam/repo/netdem/src/dem/model_linear_spring.hpp
• /Users/lzhshou/Documents/Research/myProjects/apaam/repo/netdem/src/dem/model_linear_spring.cpp