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Structure

AbstractKernel_ class is an abstract class for physics kernel.

Workflow​

Kernel-Workflow

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TYPE, ABSTRACT :: AbstractKernel_
  LOGICAL(LGT) :: isInitiated = .FALSE.
  !! This variable is Set to true when we initiate the kernel
  LOGICAL(LGT) :: isCommonDomain = .TRUE.
  !! This variable is True when the domain is common
  !! It is useful in the case of multi-physics simulations.
  !! In multi-physics applications different fields can have different
  !! type and order of shape functions. To construct such shape functions
  !! we may have to use different finite element meshes (hence, domains).
  !! For example, in the fluid mechanics, we often use Taylor-Hood element
  !! Which employs different order of interpolation for pressure and velocity.
  !! NOTE: In most of the application isCommonDomain is TRUE.
  TYPE(String) :: name
  !! This is the name of the kernel. It can be anything you want.
  TYPE(String) :: engine
  !! Which type of linear solver library (engine) we use to
  !! solve system of linear equations. We can specify following
  !! values.
  !! `NATIVE_SERIAL`
  !! `NATIVE_OMP`
  !! `NATIVE_MPI`
  !! `LIS_SERIAL`
  !! `LIS_OMP`
  !! `LIS_MPI`
  !! `PETSC`
  INTEGER(I4B) :: coordinateSystem = DEFAULT_coordinateSystem
  !! Spatial coordinate system type. It can take following values
  !! `KERNEL_CARTESIAN` for Cartesian coordinates
  !! `KERNEL_CYLINDRICAL` for Cylinderical coordinates
  !! `KERNEL_SPHERICAL` for Sperical coordinates
  !! NOTE: These parameters are defined in the AbstractKernelParam module.
  INTEGER(I4B) :: maxIter = DEFAULT_maxIter
  !! Maximum  number of iteration iterations
  !! This is useful when when we use iterative solvers like
  !! Newton method, Modified Newton method, or Iterative-predictor solvers.
  !! NOTE: DEFAULT_maxIter is defined in AbstractKernelParam
  INTEGER(I4B) :: timeDependency = 0
  !! This variable indicates if the problem is time dependent or not.
  !! It can take following values:
  !! KERNEL_STEADY  or KERNEL_STATIC
  !! KERNEL_PSEUDOSTATIC
  !! KERNEL_TRANSIENT or KERNEL_DYNAMIC
  !! NOTE: These variables are defined in AbstractKernelParam
  INTEGER(I4B) :: nsd = 0
  !! Spatial dimension of the problem,
  INTEGER(I4B) :: nnt = 1
  !! Number of nodes in time element
  !! NOTE: This variables is used only in space-time finite element methods
  INTEGER(I4B) :: tdof = 0
  !! Total number of degree of freedom per node
  !! NOTE: This variable is Set internally by each kernel while
  !! Setting the kernel.
  REAL(DFP) :: normRHS = 0.0_DFP
  !! norm of the right-hand-side vector in the system of linear equations
  !! NOTE: This variable is used internally
  REAL(DFP) :: dt = 0.0_DFP
  !! Time step size used in the pseudostatic and dynamic problems
  !! Needed in transient case
  REAL(DFP) :: startTime = 0.0
  !! Starting time of simulation
  !! NOTE: This varible is needed in the transient or pseudostatic simulation
  !! only.
  REAL(DFP) :: endTime = 0.0
  !! Final time of the simulation
  !! NOTE: This varible is needed in the transient or pseudostatic simulation
  !! only.
  REAL(DFP) :: currentTime = 0.0
  !! The current time of the simulation
  !! NOTE: This varible is needed in the transient simulation only.
  INTEGER(I4B) :: currentTimeStep = 1
  !! Current time step number of the simulation.
  !! NOTE: This varible is needed in the transient simulation only.
  INTEGER(I4B) :: totalTimeStep = 0
  !! Total number of time step number in the simulation.
  !! NOTE: This varible is needed in the transient simulation only.
  REAL(DFP) :: lengthScale = 1.0_DFP
  !! This variable denotes the length scale of the problem.
  !! NOTE: This variable is for internal use only.
  !! INTERNAL:
  INTEGER(I4B) :: postProcessOpt = 0
  !! Postprocessing options
  !! INFO: The actual action depends upon the specific kernels
  REAL(DFP) :: gravity(3) = 0.0_DFP
  !! Acceleration vector due to gravity
  TYPE(IterationData_) :: iterData
  !! Iteration data
  !! INFO: The actual action depends upon the specific kernels
  INTEGER(I4B), ALLOCATABLE :: elemToMatId(:, :)
  !! This variable denotes the Element number to material mapping.
  !! For example, `elemToMatID( iel, POROUS_MATERIAL_ID )` denotes the
  !! porous material type assigned to element number `iel`
  !! Similarly, `elemToMatID( iel, FLUID_MATERIAL_ID )` denotes
  !! the fluid material type assigned to element number `iel`.
  INTEGER(I4B), ALLOCATABLE :: dbcIndx(:)
  !! Indices where Dirichlet boundary conditions is prescribed
  !! INFO: This variable is for internal use only.
  !! It is formed from the Dirichlet boundary conditions.
  !! INTERNAL:
  CLASS(AbstractLinSolver_), POINTER :: linsol => NULL()
  !! A pointer to a Linear iterative solver
  !! NOTE: The actual linear solver depends upon the
  !! engine and type of problem. linsol is initiated in
  !! KernelInitiateFromParam routine.
  CLASS(AbstractMatrixField_), POINTER :: tanmat => NULL()
  !! Global tangent matrix
  !! NOTE: The actual form of tangent matrix depends upon the engine
  !! and type of problem.
  CLASS(Domain_), POINTER :: dom => NULL()
  !! Domain of the problem
  TYPE(DomainPointer_), ALLOCATABLE :: domains(:)
  !! Domain of the problem
  TYPE(ReferenceLine_) :: refTimeElem
  !! reference element for time domain
  TYPE(ReferenceLine_) :: refLinTimeElem
  !! reference element for time domain
  TYPE(String) :: baseContinuityForSpace
  !! Continuity of basis function in space
  TYPE(String) :: baseInterpolationForSpace
  !! Interpolation of shape function in space
  TYPE(String) :: quadratureTypeForSpace
  !! Quadrature type in space
  INTEGER(I4B) :: quadTypeForSpace
  !! Quadrature type in space
  INTEGER(I4B) :: ipTypeForSpace = 0
  !! Interpolation grid used for Lagrange polynomials
  INTEGER(I4B) :: basisTypeForSpace = 0
  !! Basis type for space
  REAL(DFP) :: alphaForSpace = 0.0_DFP
  !! Parameter for Jacobi polynomials in space
  REAL(DFP) :: betaForSpace = 0.0_DFP
  !! Parameter for Jacobi polynomials in space
  REAL(DFP) :: lambdaForSpace = 0.0_DFP
  !! Parameter for Ultraspherical polynomials in  space
  TYPE(String) :: baseContinuityForTime
  !! Continuity of basis function in time in time domain
  TYPE(String) :: baseInterpolationForTime
  !! Interpolation of basis function in time
  TYPE(String) :: quadratureTypeForTime
  !! Quadrature type in time
  INTEGER(I4B) :: quadTypeForTime
  !! Quadrature type in time
  INTEGER(I4B) :: ipTypeForTime
  !! Interpolation grid used for Lagrange polynomials
  INTEGER(I4B) :: basisTypeForTime
  !! Basis type for space
  REAL(DFP) :: alphaForTime = 0.0_DFP
  !! Parameter for Jacobi polynomials in space
  REAL(DFP) :: betaForTime = 0.0_DFP
  !! Parameter for Jacobi polynomials in space
  REAL(DFP) :: lambdaForTime = 0.0_DFP
  !! Parameter for Ultraspherical polynomials in space
  TYPE(String) :: domainFile
  !! Domain file name
  TYPE(QuadraturePoint_), ALLOCATABLE :: quadratureForSpace(:)
  !! Quadrature points in space element
  !! The size of quadratureForSpace is same as the total number of
  !! mesh in the domain
  TYPE(QuadraturePoint_) :: quadratureForTime
  !! Quadrature points in time element
  !! INFO: This is used in space-time computation
  TYPE(FiniteElementPointer_), ALLOCATABLE :: cellFE(:)
  !! Cell finite element
  TYPE(FiniteElementPointer_), ALLOCATABLE :: linCellFE(:)
  !! Linear cell finite element
  TYPE(FiniteElementPointer_), ALLOCATABLE :: facetFE(:)
  !! Facet finite element
  TYPE(FiniteElementPointer_), ALLOCATABLE :: linFacetFE(:)
  !! Linear facet finite element
  TYPE(FiniteElementPointer_), ALLOCATABLE :: edgeFE(:)
  !! Edge finite element
  TYPE(FiniteElementPointer_), ALLOCATABLE :: linEdgeFE(:)
  !! Linear edge finite element
  TYPE(FiniteElement_) :: timeFE
  !! Time finite element
  TYPE(FiniteElement_) :: linTimeFE
  !! Linear time finite element
  TYPE(ElemshapeData_) :: linTimeElemSD
    !! Element shape data on linear time element #STFEM
  TYPE(ElemshapeData_) :: timeElemSD
    !! Element shape data on time element #STFEM
  TYPE(ElemshapeData_), ALLOCATABLE :: linSpaceElemSD(:)
    !! Element shape data on linear space (simplex) element
  TYPE(ElemshapeData_), ALLOCATABLE :: spaceElemSD(:)
    !! Element shape data on space element
  TYPE(STElemshapeData_), ALLOCATABLE :: stelemsd(:, :)
    !! Element shape data on space-time element
END TYPE

isInitiated​

This is set to true when the kernel is initiated.

isCommonDomain​

This is set to true when single domain is used for several physical variables. This is applicable to multi-physics problems, only.

name​

It is the name of the kernel

engine​

Linear solver engine name, following engines are possible:

  • NATIVE_SERIAL
  • NATIVE_OMP
  • NATIVE_MPI
  • LIS_SERIAL
  • LIS_OMP
  • LIS_MPI
  • PETSC
info

Default engine is NATIVE_SERIAL

coordinateSystem​

Spatial coordinate type and spatial dimension of partial differential equations.

Possible options are given below.

  • KERNEL_1D_H
  • KERNEL_1D_V,
  • KERNEL_2D,
  • KERNEL_2D_AXISYM,
  • KERNEL_3D,
  • KERNEL_2D_PLANE_STRESS,
  • KERNEL_2D_PLANE_STRAIN

timeDependency​

It represents the time dependency of partial differential equations.

  • KERNEL_STATIC,
  • KERNEL_PSEUDOSTATIC,
  • KERNEL_TRANSIENT

nsd​

Spatial dimension of the problem, it will be determined from coordinateSystem

nnt​

Number of nodes in time domain, required for space-time finite element computation.

tdof​

Total number of degree of freedom per node. Internal use only

normRHS​

Norm of right-hand side vector. Internal use only

dt​

Time step size used in the kernel. This is needed in transient case only.

startTime​

present time of simulation needed in transient case

endTime​

Final time of simulation, needed in transient case

currentTime​

Current time, needed in transient case

lengthScale​

Length scale of the problem

currentTimeStep​

present time step number, needed in transient case

totalTimeStep​

total number of time steps, needed in transient case

postProcessOpt​

post-processing options

gravity​

Acceleration vector due to gravity

iterData​

contains information about the iteration ; such maximum number of iteration, ConvergenceType, toleranceIn, and many others, see IterationData

elemToMatId​

element number to material mapping, elemToMatID( iel, POROUS_MATERIAL_ID ) denotes the porous material type assigned to iel. Similarly, elemToMatID( iel, FLUID_MATERIAL_ID ) denotes the fluid material type assigned to iel

linsol​

Linear iterative solver

tanmat​

Global tangent matrix

refTimeElem​

reference element for time domain

refLinTimeElem​

reference element for time domain

baseContinuityForSpace​

Continuity of basis function for pressure and velocity field

baseInterpolationForSpace​

Interpolation of shape function for pressure and velocity field

quadratureTypeForSpace​

Quadrature type for pressure field

baseContinuityForTime​

Continuity of basis function for pressure field in time domain

baseInterpolationForTime​

Interpolation of basis function for pressure field in time domain

quadratureTypeForTime​

Quadrature type for pressure field in time domain