RichardsLMH Class Reference

Edge lumped mixed-hybrid solution of unsteady Darcy flow. More...

#include <richards_lmh.hh>

Inheritance diagram for RichardsLMH:

Collaboration diagram for RichardsLMH:

Classes
class	EqData

Public Member Functions
	RichardsLMH (Mesh &mesh, const Input::Record in_rec)
Public Member Functions inherited from DarcyMH
	TYPEDEF_ERR_INFO (EI_Reason, string)
	DECLARE_EXCEPTION (ExcSolverDiverge,<< "Diverged nonlinear solver. Reason: "<< EI_Reason::val)
	DECLARE_INPUT_EXCEPTION (ExcMissingTimeGovernor,<< "Missing the key 'time', obligatory for the transient problems.")
	DarcyMH (Mesh &mesh, const Input::Record in_rec)
	CREATE AND FILL GLOBAL MH MATRIX OF THE WATER MODEL. More...
const MH_DofHandler &	get_mh_dofhandler () override
void	init_eq_data ()
void	initialize () override
void	zero_time_step () override
void	update_solution () override
void	get_solution_vector (double *&vec, unsigned int &vec_size) override
void	get_parallel_solution_vector (Vec &vector) override
virtual void	output_data () override
	Write computed fields. More...
virtual	~DarcyMH () override
Public Member Functions inherited from DarcyFlowInterface
	DarcyFlowInterface (Mesh &mesh, const Input::Record in_rec)
virtual	~DarcyFlowInterface ()
Public Member Functions inherited from EquationBase
	EquationBase ()
	EquationBase (Mesh &mesh, const Input::Record in_rec)
virtual	~EquationBase ()
virtual void	choose_next_time ()
virtual void	set_time_upper_constraint (double dt, std::string message)
virtual void	set_time_lower_constraint (double dt, std::string message)
TimeGovernor &	time ()
virtual void	set_time_governor (TimeGovernor &time)
double	planned_time ()
double	solved_time ()
Mesh &	mesh ()
TimeMark::Type	mark_type ()
FieldSet &	data ()

Static Public Member Functions
static const Input::Type::Record &	get_input_type ()
Static Public Member Functions inherited from DarcyMH
static const Input::Type::Selection &	get_mh_mortar_selection ()
	Selection for enum MortarMethod. More...
static const Input::Type::Record &	type_field_descriptor ()
static const Input::Type::Record &	get_input_type ()
Static Public Member Functions inherited from DarcyFlowInterface
static Input::Type::Abstract &	get_input_type ()

Protected Member Functions
bool	zero_time_term (bool time_global=false) override
void	initialize_specific () override
void	assembly_source_term () override
	Source term is implemented differently in LMH version. More...
void	read_initial_condition () override
void	assembly_linear_system () override
void	setup_time_term () override
void	prepare_new_time_step () override
	postprocess velocity field (add sources) More...
void	postprocess () override
Protected Member Functions inherited from DarcyMH
void	solve_nonlinear ()
	Solve method common to zero_time_step and update solution. More...
void	make_serial_scatter ()
void	modify_system ()
void	create_linear_system (Input::AbstractRecord rec)
	Initialize global_row_4_sub_row. More...
void	allocate_mh_matrix ()
void	assembly_mh_matrix (MultidimAssembly &assembler)
void	set_mesh_data_for_bddc (LinSys_BDDC *bddc_ls)
virtual double	solution_precision () const
void	print_matlab_matrix (string matlab_file)
	Print darcy flow matrix in matlab format into a file. More...

Static Protected Attributes
static const int	registrar
	Registrar of class to factory. More...

Private Attributes
std::shared_ptr< EqData >	data_
VecScatter	solution_2_edge_scatter_
	PETSC scatter from the solution vector to the parallel edge vector with ghost values. More...

Additional Inherited Members
Public Types inherited from DarcyMH
enum	MortarMethod { NoMortar = 0, MortarP0 = 1, MortarP1 = 2 }
	Type of experimental Mortar-like method for non-compatible 1d-2d interaction. More...
typedef std::vector< std::shared_ptr< AssemblyBase > >	MultidimAssembly
Public Types inherited from DarcyFlowInterface
typedef DarcyFlowInterface	FactoryBaseType
	Typedef for usage of Input::Factory in child classes. More...
Protected Attributes inherited from DarcyMH
bool	solution_changed_for_scatter
MH_DofHandler	mh_dh
std::shared_ptr< Balance >	balance_
DarcyFlowMHOutput *	output_object
int	size
int	n_schur_compls
double *	solution
bool	use_steady_assembly_
bool	data_changed_
double	tolerance_
unsigned int	min_n_it_
unsigned int	max_n_it_
unsigned int	nonlinear_iteration_
LinSys *	schur0
Vec	sol_vec
VecScatter	par_to_all
Vec	steady_diagonal
Vec	steady_rhs
Vec	new_diagonal
Vec	previous_solution
std::shared_ptr< EqData >	data_
Protected Attributes inherited from EquationBase
bool	equation_empty_
	flag is true if only default constructor was called More...
Mesh *	mesh_
TimeGovernor *	time_
Input::Record	input_record_
FieldSet *	eq_data_
std::shared_ptr< Balance >	balance_
	object for calculation and writing the mass balance to file. More...

Detailed Description

Edge lumped mixed-hybrid solution of unsteady Darcy flow.

The time term and sources are evenly distributed form an element to its edges. This applies directly to the second Schur complement. After this system for pressure traces is solved we reconstruct pressures and side flows as follows:

1. Element pressure is average of edge pressure. This is in fact same as the MH for steady case so we let SchurComplement class do its job.
2. We let SchurComplement to reconstruct fluxes and then account time term and sources which are evenly distributed from an element to its sides. It can be proved, that this keeps continuity of the fluxes over the edges.

This lumping technique preserves discrete maximum principle for any time step provided one use acute mesh. But in practice even worse meshes are tractable.

Ideas how to unify steady and unsteady flow: zero_time_step:

1. Set initial time.
2. Read initial condition. Reconstruct pressures.
3. Assembly system (possibly in matrix free way).
4. Reconstruct velocities (schur complement resolve).
5. Solve iteratively as regular time step if an input flag "steady_initial_time" is set.
6. (Detect that there is no time term. I such case use arbitrary long time step up to next change of data. Some kind of time step estimator would be nice.

update solution:

1. Move to the next time.
2. Update fields
3. Nonlinear solve.
4. In case of slow convergence, use shorter time-step, within estimated limits. Otherwise there is a different problem.

Definition at line 61 of file richards_lmh.hh.

Constructor & Destructor Documentation

RichardsLMH::RichardsLMH	(	Mesh &	mesh,
		const Input::Record	in_rec
	)

Definition at line 109 of file richards_lmh.cc.

Member Function Documentation

void RichardsLMH::assembly_linear_system ( )

overrideprotectedvirtual

Assembly or update whole linear system.

Reimplemented from DarcyMH.

Definition at line 218 of file richards_lmh.cc.

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void RichardsLMH::assembly_source_term ( )

overrideprotectedvirtual

Source term is implemented differently in LMH version.

Reimplemented from DarcyMH.

Definition at line 155 of file richards_lmh.cc.

const it::Record & RichardsLMH::get_input_type ( )

static

Definition at line 72 of file richards_lmh.cc.

void RichardsLMH::initialize_specific ( )

overrideprotectedvirtual

Reimplemented from DarcyMH.

Definition at line 118 of file richards_lmh.cc.

void RichardsLMH::postprocess ( )

overrideprotectedvirtual

Reimplemented from DarcyMH.

Definition at line 274 of file richards_lmh.cc.

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void RichardsLMH::prepare_new_time_step ( )

overrideprotectedvirtual

postprocess velocity field (add sources)

Reimplemented from DarcyMH.

Definition at line 197 of file richards_lmh.cc.

void RichardsLMH::read_initial_condition ( )

overrideprotectedvirtual

Read initial condition into solution vector. Must be called after create_linear_system.

For the LMH scheme we have to be able to save edge pressures in order to restart simulation or use results of one simulation as initial condition for other one.

Reimplemented from DarcyMH.

Definition at line 161 of file richards_lmh.cc.

void RichardsLMH::setup_time_term ( )

overrideprotectedvirtual

Reimplemented from DarcyMH.

Definition at line 265 of file richards_lmh.cc.

bool RichardsLMH::zero_time_term ( bool  time_global = false )

overrideprotectedvirtual

Returns true is the fields involved in the time term have values that makes the time term zero. For time_global==true, it returns true if there are no field descriptors in the input list, so the fields )of the time ter) have their default values for whole simulation. If time_global==false (default), only the actual values are considered.

Reimplemented from DarcyMH.

Definition at line 204 of file richards_lmh.cc.

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Member Data Documentation

std::shared_ptr<EqData> RichardsLMH::data_

private

Definition at line 114 of file richards_lmh.hh.

const int RichardsLMH::registrar

staticprotected

Initial value:

=
        Input::register_class< RichardsLMH, Mesh &, const Input::Record >("Flow_Richards_LMH") +
        RichardsLMH::get_input_type().size()

Registrar of class to factory.

Definition at line 99 of file richards_lmh.hh.

VecScatter RichardsLMH::solution_2_edge_scatter_

private

PETSC scatter from the solution vector to the parallel edge vector with ghost values.

Definition at line 116 of file richards_lmh.hh.

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

• /opt/flow123d/flow123d/src/flow/richards_lmh.hh
• /opt/flow123d/flow123d/src/flow/richards_lmh.cc