Template Class NavierStokesSolver

• Defined in File navier_stokes.h

Inheritance Relationships

Base Type

• public dealii::EnableObserverPointer

Class Documentation

template<int dim, int spacedim = dim>
class NavierStokesSolver : public dealii::EnableObserverPointer

Distributed mixed finite-element solver for transient Stokes/Navier&#8212;Stokes.

The solver deliberately follows the lifecycle of PoissonSolver: grid creation, finite-element setup, algebraic setup, assembly, solve, output, and a small explicit time-stepping driver. A single Problem owns the native two-block algebraic system [velocity, pressure].

The default finite-element pair is Taylor&#8212;Hood Q_k/Q_{k-1}. The pressure is normalized by constraining one pressure degree of freedom to zero. This is a direct algebraic pressure normalization; it removes the constant nullspace without adding a third Lagrange-multiplier block.

This first implementation supports full-dimensional two- and three- dimensional meshes only (dim == spacedim). It has no elasticity, immersed-boundary, coupling, ALE, or external time-integrator dependency.

Public Types

using VectorType = LA::MPI::Vector

using BlockVectorType = LA::MPI::BlockVector

Public Functions

explicit NavierStokesSolver(const NavierStokesParameters<dim, spacedim> &par)

void make_grid()

void setup_fe()

void setup_system()

void assemble_system()

Assemble the time-discrete system at the current time.

void solve()

Solve the currently assembled two-block saddle-point system.

void output_results() const

void advance_one_timestep()

Advance one backward-Euler step and accept its solution.

void run()

Run the complete transient lifecycle.

void accept_state(const VectorType &velocity, const VectorType &pressure, double time, unsigned int step_number)

Accept semantic velocity and pressure fields from an external solver.

dealii::types::global_dof_index n_dofs() const

unsigned int n_time_steps() const

unsigned int timestep_number() const

double solution_l2_norm() const

bool solution_is_finite() const

double system_residual_l2_norm() const

double divergence_l2_norm() const

double current_time() const

double time_step() const

const dealii::parallel::TriangulationBase<dim, spacedim> &triangulation() const

const dealii::DoFHandler<dim, spacedim> &dof_handler() const

const dealii::FiniteElement<dim, spacedim> &finite_element() const

const dealii::Mapping<dim, spacedim> &mapping() const

const dealii::AffineConstraints<double> &constraints() const

const LA::MPI::BlockSparseMatrix &system_matrix() const

const LA::MPI::BlockSparseMatrix &mass_matrix() const

const LA::MPI::BlockSparseMatrix &continuous_operator() const

Return the continuous spatial Stokes operator [A,-B^T;-B,0].

const LA::MPI::SparseMatrix &velocity_mass_matrix() const

Return the physical velocity mass matrix without the density factor.

const LA::MPI::SparseMatrix &pressure_metric_matrix() const

Return the pressure metric used only by the native preconditioner.

void velocity_forcing_at_time(double time, LA::MPI::Vector &destination) const

Assemble the unscaled velocity forcing vector at an external time.

const BlockVectorType &system_rhs() const

const BlockVectorType &solution() const

const BlockVectorType &previous_solution() const

const BlockVectorType &locally_relevant_solution() const

const dealii::IndexSet &locally_owned_dofs() const

const dealii::IndexSet &locally_relevant_dofs() const

const std::vector<dealii::IndexSet> &locally_owned_dofs_by_block() const

const std::vector<dealii::IndexSet> &locally_relevant_dofs_by_block() const

const dealii::FEValuesExtractors::Vector &velocity_extractor() const

const dealii::FEValuesExtractors::Scalar &pressure_extractor() const

const dealii::ComponentMask &velocity_component_mask() const

double density() const

Return the physical density used by the continuous velocity equation.

double viscosity() const

Return the physical viscosity used by the continuous velocity equation.

bool include_convective_term() const

Whether the semidiscrete contributor includes the convective term.

dealii::types::global_dof_index velocity_block_size() const

Return the global mixed-block offset of the pressure block.

void set_solution(const BlockVectorType &new_solution)

Replace the accepted state and use it as the next-step history.