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structural_mechanics_model.hh
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			/**
			* Copyright (©) 2011-2023 EPFL (Ecole Polytechnique Fédérale de Lausanne)
			* Laboratory (LSMS - Laboratoire de Simulation en Mécanique des Solides)
			*
			* This file is part of Akantu
			*
			* Akantu is free software: you can redistribute it and/or modify it under the
			* terms of the GNU Lesser General Public License as published by the Free
			* Software Foundation, either version 3 of the License, or (at your option) any
			* later version.
			*
			* Akantu is distributed in the hope that it will be useful, but WITHOUT ANY
			* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
			* A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
			* details.
			*
			* You should have received a copy of the GNU Lesser General Public License
			* along with Akantu. If not, see <http://www.gnu.org/licenses/>.
			*/

			/* -------------------------------------------------------------------------- */
			#include "aka_named_argument.hh"
			#include "model.hh"
			/* -------------------------------------------------------------------------- */

			#ifndef AKANTU_STRUCTURAL_MECHANICS_MODEL_HH_
			#define AKANTU_STRUCTURAL_MECHANICS_MODEL_HH_

			/* -------------------------------------------------------------------------- */
			namespace akantu {
			class Material;
			class MaterialSelector;
			class DumperIOHelper;
			class NonLocalManager;
			template <ElementKind kind, class IntegrationOrderFunctor>
			class IntegratorGauss;
			template <ElementKind kind> class ShapeStructural;
			} // namespace akantu

			namespace akantu {

			struct StructuralMaterial {
			Real E{0};
			Real A{1};
			Real I{0};
			Real Iz{0};
			Real Iy{0};
			Real GJ{0};
			Real rho{0};
			Real t{0};
			Real nu{0};
			};

			class StructuralMechanicsModel : public Model {
			/* ------------------------------------------------------------------------ */
			/* Constructors/Destructors */
			/* ------------------------------------------------------------------------ */
			public:
			using MyFEEngineType =
			FEEngineTemplate<IntegratorGauss, ShapeStructural, _ek_structural>;

			StructuralMechanicsModel(Mesh & mesh, Int dim = _all_dimensions,
			const ID & id = "structural_mechanics_model");

			~StructuralMechanicsModel() override;

			/// Init full model
			void initFullImpl(const ModelOptions & options) override;

			/// Init boundary FEEngine
			void initFEEngineBoundary() override;

			/* ------------------------------------------------------------------------ */
			/* Virtual methods from SolverCallback */
			/* ------------------------------------------------------------------------ */
			/// get the type of matrix needed
			MatrixType getMatrixType(const ID & matrix_id) const override;

			/// callback to assemble a Matrix
			void assembleMatrix(const ID & matrix_id) override;

			/// callback to assemble a lumped Matrix
			void assembleLumpedMatrix(const ID & matrix_id) override;

			/// callback to assemble the residual (rhs)
			void assembleResidual() override;

			void assembleResidual(const ID & residual_part) override;

			bool canSplitResidual() const override { return true; }

			void afterSolveStep(bool converged) override;

			/// compute kinetic energy
			Real getKineticEnergy();

			/// compute potential energy
			Real getPotentialEnergy();

			/// compute the specified energy
			Real getEnergy(const ID & energy);

			/**
			* \brief This function computes the an approximation of the lumped mass.
			*
			* The mass is computed by looping over all beams and computing their mass.
			* The mass of a single beam is computed by the (initial) length of the beam,
			* its cross sectional area and its density.
			* The beam mass is then equaly distributed among the two nodes.
			*
			* For computing the rotational inertia, the function assumes that the mass of
			* a node is uniformaly distributed inside a disc (2D) or a sphere (3D). The
			* size of that disc, depends on the volume of the beam.
			*
			* Note that the computation of the mass is not unambigius.
			* The reason for this is, that the units of `StructralMaterial::rho` are not
			* clear. By default the function assumes that its unit are 'Mass per Volume'.
			* However, this makes the computed mass different than the consistent mass,
			* which seams to assume that its units are 'mass per unit length'.
			* The main difference between thge two are not the values, but that the
			* first version depends on `StructuralMaterial::A` while the later does not.
			* By defining the macro `AKANTU_STRUCTURAL_MECHANICS_CONSISTENT_LUMPED_MASS`
			* the function will compute the mass in a way that is consistent with the
			* consistent mass matrix.
			*
			* \note The lumped mass is not stored inside the DOFManager.
			*
			* \param ghost_type Should ghost types be computed.
			*/
			void assembleLumpedMassMatrix();

			/* ------------------------------------------------------------------------ */
			/* Virtual methods from Model */
			/* ------------------------------------------------------------------------ */
			protected:
			/// get some default values for derived classes
			std::tuple<ID, TimeStepSolverType>
			getDefaultSolverID(const AnalysisMethod & method) override;

			ModelSolverOptions
			getDefaultSolverOptions(const TimeStepSolverType & type) const override;

			static UInt getNbDegreeOfFreedom(ElementType type);

			/* ------------------------------------------------------------------------ */
			/* Methods */
			/* ------------------------------------------------------------------------ */
			void initSolver(TimeStepSolverType time_step_solver_type,
			NonLinearSolverType non_linear_solver_type) override;

			/// initialize the model
			void initModel() override;

			/// compute the stresses per elements
			void computeStresses();

			/// compute the nodal forces
			void assembleInternalForce();

			/// compute the nodal forces for an element type
			void assembleInternalForce(ElementType type, GhostType gt);

			/// assemble the stiffness matrix
			void assembleStiffnessMatrix();

			/// assemble the mass matrix for consistent mass resolutions
			void assembleMassMatrix();

			protected:
			/// assemble the mass matrix for either _ghost or _not_ghost elements
			void assembleMassMatrix(GhostType ghost_type);

			/// computes rho
			void computeRho(Array<Real> & rho, ElementType type, GhostType ghost_type);

			/// finish the computation of residual to solve in increment
			void updateResidualInternal();

			/* ------------------------------------------------------------------------ */
			private:
			template <ElementType type> void assembleStiffnessMatrix();
			template <ElementType type> void computeStressOnQuad();
			template <ElementType type>
			void computeTangentModuli(Array<Real> & tangent_moduli);

			/* ------------------------------------------------------------------------ */
			/* Dumpable interface */
			/* ------------------------------------------------------------------------ */
			public:
			std::shared_ptr<dumpers::Field>
			createNodalFieldReal(const std::string & field_name,
			const std::string & group_name,
			bool padding_flag) override;

			std::shared_ptr<dumpers::Field>
			createNodalFieldBool(const std::string & field_name,
			const std::string & group_name,
			bool padding_flag) override;

			std::shared_ptr<dumpers::Field>
			createElementalField(const std::string & field_name,
			const std::string & group_name, bool padding_flag,
			Int spatial_dimension, ElementKind kind) override;

			/* ------------------------------------------------------------------------ */
			/* Accessors */
			/* ------------------------------------------------------------------------ */
			public:
			/// set the value of the time step
			void setTimeStep(Real time_step, const ID & solver_id = "") override;

			/// get the StructuralMechanicsModel::displacement vector
			AKANTU_GET_MACRO(Displacement, *displacement_rotation, Array<Real> &);

			/// get the StructuralMechanicsModel::velocity vector
			AKANTU_GET_MACRO(Velocity, *velocity, Array<Real> &);

			/// get the StructuralMechanicsModel::acceleration vector, updated
			/// by
			/// StructuralMechanicsModel::updateAcceleration
			AKANTU_GET_MACRO(Acceleration, *acceleration, Array<Real> &);

			/// get the StructuralMechanicsModel::external_force vector
			AKANTU_GET_MACRO(ExternalForce, *external_force, Array<Real> &);

			/// get the StructuralMechanicsModel::internal_force vector (boundary forces)
			AKANTU_GET_MACRO(InternalForce, *internal_force, Array<Real> &);

			/// get the StructuralMechanicsModel::boundary vector
			AKANTU_GET_MACRO(BlockedDOFs, *blocked_dofs, Array<bool> &);

			/**
			* Returns a const reference to the array that stores the lumped mass.
			*
			* The returned array has dimension `N x d` where `N` is the number of nodes
			* and `d`, is the number of degrees of freedom per node.
			*/
			inline const Array<Real> & getLumpedMass() const {
			if (this->mass == nullptr) {
			AKANTU_EXCEPTION("The pointer to the mass was not allocated.");
			};
			return *(this->mass);
			};

			// These function is an alias, for compability with the solid mechanics
			inline const Array<Real> & getMass() const { return this->getLumpedMass(); }

			// Creates the array for storing the mass
			bool allocateLumpedMassArray();

			/**
			* Tests if *this has a lumped mass pointer.
			*/
			inline bool hasLumpedMass() const { return (this->mass != nullptr); };

			AKANTU_GET_MACRO_BY_ELEMENT_TYPE_CONST(RotationMatrix, rotation_matrix, Real);

			AKANTU_GET_MACRO_BY_ELEMENT_TYPE_CONST(Stress, stress, Real);

			AKANTU_GET_MACRO_BY_ELEMENT_TYPE(ElementMaterial, element_material, UInt);

			AKANTU_GET_MACRO_BY_ELEMENT_TYPE(Set_ID, set_ID, UInt);

			/**
			* \brief This function adds the `StructuralMaterial` material to the list of
			* materials managed by *this.
			*
			* It is important that this function might invalidate all references to
			* structural materials, that were previously optained by `getMaterial()`.
			*
			* \param material The new material.
			* \param name the name associated to this material
			*
			* \return The ID of the material that was added.
			*
			* \note The return type is is new.
			*/
			UInt addMaterial(StructuralMaterial & material, const ID & name = "");

			const StructuralMaterial &
			getMaterialByElement(const Element & element) const;

			/**
			* \brief Returns the ith material of *this.
			* \param material_index The index of requested material
			*/
			const StructuralMaterial & getMaterial(UInt material_index) const;

			const StructuralMaterial & getMaterial(const ID & name) const;

			/**
			* \brief Returns the number of the different materials inside *this.
			*/
			UInt getNbMaterials() const { return materials.size(); }

			/* ------------------------------------------------------------------------ */
			/* Boundaries (structural_mechanics_model_boundary.cc) */
			/* ------------------------------------------------------------------------ */
			public:
			/// Compute Linear load function set in global axis
			void computeForcesByGlobalTractionArray(const Array<Real> & traction_global,
			ElementType type);

			/// Compute Linear load function set in local axis
			void computeForcesByLocalTractionArray(const Array<Real> & tractions,
			ElementType type);

			/* ------------------------------------------------------------------------ */
			/* Class Members */
			/* ------------------------------------------------------------------------ */
			private:
			/// time step
			Real time_step;

			/// conversion coefficient form force/mass to acceleration
			Real f_m2a;

			/// displacements array
			std::unique_ptr<Array<Real>> displacement_rotation;

			/// velocities array
			std::unique_ptr<Array<Real>> velocity;

			/// accelerations array
			std::unique_ptr<Array<Real>> acceleration;

			/// forces array
			std::unique_ptr<Array<Real>> internal_force;

			/// forces array
			std::unique_ptr<Array<Real>> external_force;

			/**
			* \brief This is the "lumped" mass array.
			*
			* It is a bit special, since it is not a one dimensional array, bit it is
			* actually a matrix. The number of rows equals the number of nodes. The
			* number of colums equals the number of degrees of freedoms per node. This
			* layout makes the thing a bit more simple.
			*
			* Note that it is only allocated in case, the "Lumped" mode is enabled.
			*/
			std::unique_ptr<Array<Real>> mass;

			/// boundaries array
			std::unique_ptr<Array<bool>> blocked_dofs;

			/// stress array
			ElementTypeMapArray<Real> stress;

			ElementTypeMapArray<UInt> element_material;

			// Define sets of beams
			ElementTypeMapArray<UInt> set_ID;

			/// number of degre of freedom
			Int nb_degree_of_freedom;

			// Rotation matrix
			ElementTypeMapArray<Real> rotation_matrix;

			// /// analysis method check the list in akantu::AnalysisMethod
			// AnalysisMethod method;

			/// flag defining if the increment must be computed or not
			bool increment_flag;

			bool need_to_reassemble_mass{true};
			bool need_to_reassemble_stiffness{true};
			bool need_to_reassemble_lumped_mass{true};

			/* ------------------------------------------------------------------------ */
			std::vector<StructuralMaterial> materials;
			std::map<std::string, UInt> materials_names_to_id;
			};

			} // namespace akantu

			#include "structural_mechanics_model_inline_impl.hh"

			#endif /* AKANTU_STRUCTURAL_MECHANICS_MODEL_HH_ */

rAKA/src/model/structural_mechanics/structural_mechanics_model.hha67b29746942features/72-czm…

structural_mechanics_model.hhView Options

rAKA/src/model/structural_mechanics/structural_mechanics_model.hh
a67b29746942features/72-czm…

structural_mechanics_model.hh
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