Domains

A domain in Cthonios is a group of element sections and all the associated datastructures necessary to run a finite element calculation. Different types of domains are used for different problems, e.g. quasi-static vs. dynamics problems have different requirements and solution strategies.

Input file syntax example

domains:
  domain_1:
    mesh:
      ...
    boundary conditions:
      ...
    sections:
      ...
    time stepper:
      ...

Quasi-static Domain

Quasi-static domains are appropriate for problems where the following equation holds

$\nabla\cdot \mathbf{P} + \mathbf{b} = \mathbf{0},$ where $\mathbf{P}$ is the first Piola-Kirchoff stress, $\nabla$ is the gradient operator with respsect to the reference corrdinates, and $\mathbf{b}$ is a body force.

Index

Cthonios.AbstractDomain — Type

abstract type AbstractDomain

Abstract base type for domains.

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Cthonios.Domain — Type

struct Domain{M, D, S, DBCs, DDofs} <: Cthonios.AbstractDomain

mesh::Any
dof::Any
sections::Any
dirichlet_bcs::Any
dirichlet_dofs::Any

Domain type to hold information like bcs, sections, etc. Note that the DofManager unknown dofs are not automatically set. After setting up a Domain you will need to run, update_unknown_dofs!.

mesh - Handle to an open FileMesh. dof - DofManager object. sections - A set of SectionInternals. dirichlet_bcs - A set of DirichletBCInternals. dirichlet_dofs - A set of dofs to apply dirichlet dofs. This is mainly for book-keeping purposes

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Cthonios.Domain — Method

Domain(
    mesh_file::String,
    sections_in,
    dbcs_in,
    n_dofs::Int64
) -> Domain{M, D, S, _A, Vector{Int64}} where {M<:(FiniteElementContainers.FileMesh{Exodus.ExodusDatabase{M, I, B, F, Init}} where {M, I, B, F, Init}), D<:(FiniteElementContainers.DofManager{Int64, _A, _B, Vector{Float64}, _C} where {_A, _B, _C<:(AbstractArray{Int64})}), S<:NamedTuple, _A}

Constructor for a Domain type. mesh_file - File name of a mesh to read. sections_in - A set of Sections. dbcs_in - A set of DirichletBCs. n_dofs - The number of dofs in the problem.

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Cthonios.StaticAssembler — Method

StaticAssembler(
    domain::Domain
) -> FiniteElementContainers.StaticAssembler{Float64, Int64, _A, _B, _C, _D, _E, _F, _G, _H, _I, _J, _K, Vector{Int64}, Vector{Int64}, Vector{Float64}} where {_A<:AbstractVector{Int64}, _B<:AbstractVector{Int64}, _C<:AbstractVector{Int64}, _D<:AbstractVector{Int64}, _E<:AbstractVector{Int64}, _F<:FiniteElementContainers.NodalField, _G<:AbstractVector{Float64}, _H, _I, _J, _K}

some FEMContainers abuse

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Cthonios.create_fields — Method

create_fields(domain::Domain) -> Any

Create a zero field based on domain.dof.

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Cthonios.create_unknowns — Method

create_unknowns(domain::Domain) -> Any

Creates an unknown vector based on domain.dof

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Cthonios.dirichlet_dofs — Method

dirichlet_dofs(domain::Domain) -> Any

Returns a sorted and unique vector of dirichlet dofs.

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Cthonios.update_dirichlet_vals! — Method

update_dirichlet_vals!(Ubc, domain::Domain, X, t)

Updates the values in Ubc with dirichlet boundary conditions in domain. Ubc - BC values to fill. domain - Domain. X - Nodal coordinates. t - A scalar time value to use in the BC functions.

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Cthonios.update_field_bcs! — Method

update_field_bcs!(U, domain::Domain, Ubc)

Updates the Dirichlet BC dofs in U with the values in Ubc. U - Nodal field to update. domain - Domain. Ubc - BC values to fill.

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Cthonios.update_field_unknowns! — Method

update_field_unknowns!(U, domain::Domain, Uu)

Updates the unknown dofs in U with the values in Uu. U - Nodal field to update. domain - Domain. Uu - Unknown values to fill.

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Cthonios.update_unknown_dofs! — Method

update_unknown_dofs!(domain::Domain, asm)

Update the unknown dofs in domain.dof, domain.dirichlet_dofs, and asm. TODO maybe move domain.dirichlet_dofsto the$DofManager$in$FiniteElementContainers$.$domain$- Domain object.$asm$` - Assembly object.

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Cthonios.update_unknown_dofs! — Method

update_unknown_dofs!(domain::Domain)

Update the unknown dofs in domain.dof and domain.dirichlet_dofs. TODO maybe move domain.dirichlet_dofsto the$DofManager$in$FiniteElementContainers$`.

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