Library
Documenting the public user interface.
Architectures
Oceananigans.Architectures.AbstractArchitecture
— TypeAbstractArchitecture
Abstract supertype for architectures supported by Oceananigans.
Oceananigans.Architectures.CPU
— TypeCPU <: AbstractArchitecture
Run Oceananigans on a single-core of a CPU.
Oceananigans.Architectures.GPU
— TypeGPU <: AbstractArchitecture
Run Oceananigans on a single NVIDIA CUDA GPU.
Oceananigans.Architectures.@hascuda
— Macro@hascuda expr
A macro to compile and execute expr
only if CUDA is installed and available. Generally used to wrap expressions that can only be compiled if CuArrays
and CUDAnative
can be loaded.
Boundary conditions
Oceananigans.BoundaryConditions.BCType
— TypeBCType
Abstract supertype for boundary condition types.
Oceananigans.BoundaryConditions.Flux
— TypeFlux
A type specifying a boundary condition on the flux of a field.
Oceananigans.BoundaryConditions.Gradient
— TypeGradient
A type specifying a boundary condition on the derivative or gradient of a field. Also called a Neumann boundary condition.
Oceananigans.BoundaryConditions.NoPenetration
— TypeNoPenetration
A type specifying a no-penetration boundary condition for a velocity component that is normal to a wall.
Thus NoPenetration
can only be applied to u
along x, v
along y, or w
along z. For all other cases –- fields located at (Cell, Cell, Cell), or u
, v
, and w
in (y, z), (x, z), and (x, y), respectively, either Value
, Gradient
, or Flux
conditions must be used.
A condition may not be specified with a NoPenetration
boundary condition.
Note that this differs from a zero Value
boundary condition as Value
imposes values at the cell centers (and could apply to tracers) while a no-penetration boundary condition only applies to normal velocity components at a wall, where the velocity at the cell face collocated at the wall is known and set to zero.
Oceananigans.BoundaryConditions.Value
— TypeValue
A type specifying a boundary condition on the value of a field. Also called a Dirchlet boundary condition.
Oceananigans.BoundaryConditions.BoundaryCondition
— TypeBoundaryCondition{C<:BCType}(condition)
Construct a boundary condition of type C
with a condition
that may be given by a number, an array, or a function with signature:
condition(i, j, grid, time, iteration, U, Φ, parameters) = # function definition
that returns a number and where i
and j
are indices along the boundary.
Boundary condition types include Periodic
, Flux
, Value
, Gradient
, and NoPenetration
.
Oceananigans.BoundaryConditions.CoordinateBoundaryConditions
— TypeCoordinateBoundaryConditions(left, right)
A set of two BoundaryCondition
s to be applied along a coordinate x, y, or z.
The left
boundary condition is applied on the negative or lower side of the coordinate while the right
boundary condition is applied on the positive or higher side.
Oceananigans.BoundaryConditions.FieldBoundaryConditions
— TypeFieldBoundaryConditions
An alias for NamedTuple{(:x, :y, :z)}
that represents a set of three CoordinateBoundaryCondition
s applied to a field along x, y, and z.
Oceananigans.BoundaryConditions.FieldBoundaryConditions
— MethodFieldBoundaryConditions(x, y, z)
Construct a FieldBoundaryConditions
using a CoordinateBoundaryCondition
for each of the x
, y
, and z
coordinates.
Oceananigans.BoundaryConditions.FieldBoundaryConditions
— MethodFieldBoundaryConditions(grid, loc;
east = DefaultBoundaryCondition(topology(grid)[1], loc[1]),
west = DefaultBoundaryCondition(topology(grid)[1], loc[1]),
south = DefaultBoundaryCondition(topology(grid)[2], loc[2]),
north = DefaultBoundaryCondition(topology(grid)[2], loc[2]),
bottom = DefaultBoundaryCondition(topology(grid)[3], loc[3]),
top = DefaultBoundaryCondition(topology(grid)[3], loc[3]))
Construct FieldBoundaryConditions
for a field with location loc
(a 3-tuple of Face
or Cell
) defined on grid
(the grid's topology is what defined the default boundary conditions that are imposed).
Specific boundary conditions can be applied along the x dimension with the west
and east
kwargs, along the y-dimension with the south
and north
kwargs, and along the z-dimension with the bottom
and top
kwargs.
Oceananigans.BoundaryConditions.BoundaryFunction
— Type BoundaryFunction{B, X1, X2}(func, parameters=nothing)
A wrapper for the user-defined boundary condition function func
, on the boundary specified by symbol B
and at location (X1, X2)
, and with parameters
.
Example
julia> using Oceananigans, Oceananigans.BoundaryConditions, Oceananigans.Fields
julia> toptracerflux = BoundaryFunction{:z, Cell, Cell}((x, y, t) -> cos(2π*x) * cos(t)) (::BoundaryFunction{:z,Cell,Cell,var"#7#8",Nothing}) (generic function with 1 method)
julia> toptracerbc = BoundaryCondition(Flux, toptracerflux);
julia> flux_func(x, y, t, p) = cos(p.k * x) * cos(p.ω * t); # function with parameters
julia> parameterizeduvelocityflux = BoundaryFunction{:z, Face, Cell}(fluxfunc, (k=4π, ω=3.0)) (::BoundaryFunction{:z,Face,Cell,typeof(flux_func),NamedTuple{(:k, :ω),Tuple{Float64,Float64}}}) (generic function with 1 method)
julia> topubc = BoundaryCondition(Flux, parameterizeduvelocity_flux);
Oceananigans.BoundaryConditions.TracerBoundaryCondition
— MethodTracerBoundaryCondition(bctype, B, args...)
Returns a BoundaryCondition
of type bctype
, that applies the function func
to a tracer on the boundary B
, which is one of :x, :y, :z
. The boundary function has the signature
`func(ξ, η, t)`
where t
is time, and ξ
and η
are coordinates along the boundary, eg: (y, z)
for B = :x
, (x, z)
for B = :y
, or (x, y)
for B = :z
.
Oceananigans.BoundaryConditions.UVelocityBoundaryCondition
— MethodUVelocityBoundaryCondition(bctype, B, args...)
Returns a BoundaryCondition
of type bctype
, that applies the function func
to u
, the x
-velocity field, on the boundary B
, which is one of :x, :y, :z
. The boundary function has the signature
`func(ξ, η, t)`
where t
is time, and ξ
and η
are coordinates along the boundary, eg: (y, z)
for B = :x
, (x, z)
for B = :y
, or (x, y)
for B = :z
.
Oceananigans.BoundaryConditions.VVelocityBoundaryCondition
— MethodVVelocityBoundaryCondition(bctype, B, args...)
Returns a BoundaryCondition
of type bctype
, that applies the function func
to v
, the y
-velocity field, on the boundary B
, which is one of :x, :y, :z
. The boundary function has the signature
`func(ξ, η, t)`
where t
is time, and ξ
and η
are coordinates along the boundary, eg: (y, z)
for B = :x
, (x, z)
for B = :y
, or (x, y)
for B = :z
.
Oceananigans.BoundaryConditions.WVelocityBoundaryCondition
— MethodVVelocityBoundaryCondition(bctype, B, args...)
Returns a BoundaryCondition
of type bctype
, that applies the function func
to w
, the z
-velocity field, on the boundary B
, which is one of :x, :y, :z
. The boundary function has the signature
`func(ξ, η, t)`
where t
is time, and ξ
and η
are coordinates along the boundary, eg: (y, z)
for B = :x
, (x, z)
for B = :y
, or (x, y)
for B = :z
.
Oceananigans.BoundaryConditions.fill_halo_regions!
— MethodFill halo regions in x, y, and z for a given field.
Oceananigans.BoundaryConditions.fill_halo_regions!
— Methodfill_halo_regions!(fields, arch)
Fill halo regions for each field in the tuple fields
according to their boundary conditions, possibly recursing into fields
if it is a nested tuple-of-tuples.
Oceananigans.BoundaryConditions.apply_y_bcs!
— Methodapply_y_bcs!(Gc, arch, grid, args...)
Apply flux boundary conditions to a field c
by adding the associated flux divergence to the source term Gc
at the left and right.
Oceananigans.BoundaryConditions.apply_z_bcs!
— Methodapply_z_bcs!(Gc, arch, grid, args...)
Apply flux boundary conditions to a field c
by adding the associated flux divergence to the source term Gc
at the top and bottom.
Buoyancy
Oceananigans.Buoyancy.SeawaterBuoyancy
— TypeSeawaterBuoyancy{FT, EOS, T, S} <: AbstractBuoyancy{EOS}
Buoyancy model for seawater. T
and S
are either nothing
if both temperature and salinity are active, or of type FT
if temperature or salinity are constant, respectively.
Oceananigans.Buoyancy.SeawaterBuoyancy
— TypeSeawaterBuoyancy([FT=Float64;] gravitational_acceleration = g_Earth,
equation_of_state = LinearEquationOfState(FT),
constant_temperature = false, constant_salinity = false)
Returns parameters for a temperature- and salt-stratified seawater buoyancy model with a gravitational_acceleration
constant (typically called 'g'), and an equation_of_state
that related temperature and salinity (or conservative temperature and absolute salinity) to density anomalies and buoyancy. If either temperature
or salinity
are specified, buoyancy is calculated
Oceananigans.Buoyancy.∂x_b
— Method∂x_b(i, j, k, grid, b::SeawaterBuoyancy, C)
Returns the x-derivative of buoyancy for temperature and salt-stratified water,
where g
is gravitational acceleration, α
is the thermal expansion coefficient, β
is the haline contraction coefficient, Θ
is conservative temperature, and sᴬ
is absolute salinity.
Note: In Oceananigans, model.tracers.T
is conservative temperature and model.tracers.S
is absolute salinity.
Note that ∂x_Θ
, ∂x_sᴬ
, α
, and β
are all evaluated at cell interfaces in x
and cell centers in y
and z
.
Oceananigans.Buoyancy.∂y_b
— Method∂y_b(i, j, k, grid, b::SeawaterBuoyancy, C)
Returns the y-derivative of buoyancy for temperature and salt-stratified water,
where g
is gravitational acceleration, α
is the thermal expansion coefficient, β
is the haline contraction coefficient, Θ
is conservative temperature, and sᴬ
is absolute salinity.
Note: In Oceananigans, model.tracers.T
is conservative temperature and model.tracers.S
is absolute salinity.
Note that ∂y_Θ
, ∂y_sᴬ
, α
, and β
are all evaluated at cell interfaces in y
and cell centers in x
and z
.
Oceananigans.Buoyancy.∂z_b
— Method∂z_b(i, j, k, grid, b::SeawaterBuoyancy, C)
Returns the vertical derivative of buoyancy for temperature and salt-stratified water,
where g
is gravitational acceleration, α
is the thermal expansion coefficient, β
is the haline contraction coefficient, Θ
is conservative temperature, and sᴬ
is absolute salinity.
Note: In Oceananigans, model.tracers.T
is conservative temperature and model.tracers.S
is absolute salinity.
Note that ∂z_Θ
, ∂z_sᴬ
, α
, and β
are all evaluated at cell interfaces in z
and cell centers in x
and y
.
Oceananigans.Buoyancy.BuoyancyTracer
— TypeBuoyancyTracer <: AbstractBuoyancy{Nothing}
Type indicating that the tracer b
represents buoyancy.
Oceananigans.Buoyancy.LinearEquationOfState
— TypeLinearEquationOfState{FT} <: AbstractEquationOfState
Linear equation of state for seawater.
Oceananigans.Buoyancy.LinearEquationOfState
— TypeLinearEquationOfState([FT=Float64;] α=1.67e-4, β=7.80e-4)
Returns parameters for a linear equation of state for seawater with thermal expansion coefficient α
[K⁻¹] and haline contraction coefficient β
[ppt⁻¹]. The buoyancy perturbation associated with a linear equation of state is
Default constants are taken from Table 1.2 (page 33) of Vallis, "Atmospheric and Oceanic Fluid Dynamics: Fundamentals and Large-Scale Circulation" (2ed, 2017).
Oceananigans.Buoyancy.RoquetIdealizedNonlinearEquationOfState
— TypeRoquetIdealizedNonlinearEquationOfState{F, C, T} <: AbstractNonlinearEquationOfState
Parameters associated with the idealized nonlinear equation of state proposed by Roquet et al., "Defining a Simplified yet 'Realistic' Equation of State for Seawater", Journal of Physical Oceanography (2015).
Oceananigans.Buoyancy.RoquetIdealizedNonlinearEquationOfState
— TypeRoquetIdealizedNonlinearEquationOfState([FT=Float64,] flavor, ρ₀=1024.6,
polynomial_coeffs=optimized_roquet_coeffs[flavor])
Returns parameters for the idealized polynomial nonlinear equation of state with reference density ρ₀
and polynomial_coeffs
proposed by Roquet et al., "Defining a Simplified yet 'Realistic' Equation of State for Seawater", Journal of Physical Oceanography (2015). The default reference density is ρ₀ = 1024.6 kg m⁻³
, the average surface density of seawater in the world ocean.
The flavor
of the nonlinear equation of state is a symbol that selects a set of optimized polynomial coefficients defined in Table 2 of Roquet et al., "Defining a Simplified yet 'Realistic' Equation of State for Seawater", Journal of Physical Oceanography (2015), and further discussed in the text surrounding equations (12)–(15). The optimization minimizes errors in estimated horizontal density gradient estiamted from climatological temperature and salinity distributions between the 5 simplified forms chosen by Roquet et. al and the full-fledged TEOS-10 equation of state.
The equations of state define the density anomaly ρ′
, and have the polynomial form
`ρ′(T, S, D) = Σᵢⱼₐ Rᵢⱼₐ Tⁱ Sʲ Dᵃ`,
where T
is conservative temperature, S
is absolute salinity, and D
is the geopotential depth, currently just D = -z
. The Rᵢⱼₐ
are constant coefficients.
Flavors of idealized nonlinear equations of state
- `:linear`: a linear equation of state, `ρ′ = R₁₀₀ * T + R₀₁₀ * S`
- `:cabbeling`: includes quadratic temperature term,
`ρ′ = R₁₀₀ * T + R₀₁₀ * S + R₀₂₀ * T^2`
- `:cabbeling_thermobaricity`: includes 'thermobaricity' term,
`ρ′ = R₁₀₀ * T + R₀₁₀ * S + R₀₂₀ * T^2 + R₀₁₁ * T * D`
- `:freezing`: same as `:cabbeling_thermobaricity` with modified constants to increase
accuracy near freezing
- `:second_order`: includes quadratic salinity, halibaricity, and thermohaline term,
`ρ′ = R₁₀₀ * T + R₀₁₀ * S + R₀₂₀ * T^2 + R₀₁₁ * T * D`
+ R₂₀₀ * S^2 + R₁₀₁ * S * D + R₁₁₀ * S * T`
Example
julia> using Oceananigans
julia> eos = Oceananigans.RoquetIdealizedNonlinearEquationOfState(:cabbeling);
julia> eos.polynomial_coeffs (R₀₁₀ = -0.0844, R₁₀₀ = 0.7718, R₀₂₀ = -0.004561, R₀₁₁ = 0.0, R₂₀₀ = 0.0, R₁₀₁ = 0.0, R₁₁₀ = 0.0)
References
- Roquet et al., "Defining a Simplified yet 'Realistic' Equation of State for
Seawater", Journal of Physical Oceanography (2015).
- "Thermodynamic Equation of State for Seawater" (TEOS-10), http://www.teos-10.org
Coriolis
Oceananigans.Coriolis.FPlane
— TypeFPlane{FT} <: AbstractRotation
A parameter object for constant rotation around a vertical axis.
Oceananigans.Coriolis.FPlane
— TypeFPlane([FT=Float64;] f=nothing, rotation_rate=Ω_Earth, latitude=nothing)
Returns a parameter object for constant rotation at the angular frequency f/2
, and therefore with background vorticity f
, around a vertical axis. If f
is not specified, it is calculated from rotation_rate
and latitude
according to the relation `f = 2rotation_ratesind(latitude).
By default, rotation_rate
is assumed to be Earth's.
Also called FPlane
, after the "f-plane" approximation for the local effect of a planet's rotation in a planar coordinate system tangent to the planet's surface.
Oceananigans.Coriolis.NonTraditionalFPlane
— TypeNonTraditionalFPlane{FT} <: AbstractRotation
A Coriolis implementation that facilitates non-traditional Coriolis terms in the zonal and vertical momentum equations along with the traditional Coriolis terms.
Oceananigans.Coriolis.NonTraditionalFPlane
— TypeNonTraditionalFPlane([FT=Float64;] fz=nothing, fy=nothing,
rotation_rate=Ω_Earth, latitude=nothing)
Returns a parameter object for constant rotation about an axis in the y-z
plane with y
- and z
-components fy/2
and fz/2
, and the background vorticity is (0, fy, fz)
.
In oceanography fz
and fy
represent the components of planetary voriticity which are perpendicular and parallel to the ocean surface in a domain in which x, y, z
correspond to the directions east, north, and up.
If fz
and fy
are not specified, they are calculated from rotation_rate
and latitude
according to the relations fz = 2*rotation_rate*sind(latitude)
and fy = 2*rotation_rate*cosd(latitude)
, respectively. By default, rotation_rate
is assumed to be Earth's.
Oceananigans.Coriolis.BetaPlane
— TypeBetaPlane{T} <: AbstractRotation
A parameter object for meridionally increasing Coriolis parameter (f = f₀ + βy
).
Oceananigans.Coriolis.BetaPlane
— TypeBetaPlane([T=Float64;] f₀=nothing, β=nothing,
rotation_rate=Ω_Earth, latitude=nothing, radius=R_Earth)
A parameter object for meridionally increasing Coriolis parameter (f = f₀ + βy
).
The user may specify both f₀
and β
, or the three parameters rotation_rate
, latitude
, and radius
that specify the rotation rate and radius of a planet, and the central latitude at which the β
-plane approximation is to be made.
By default, the rotation_rate
and planet radius
is assumed to be Earth's.
Diagnostics
Oceananigans.Diagnostics.HorizontalAverage
— TypeHorizontalAverage{F, R, P, I, Ω} <: AbstractDiagnostic
A diagnostic for computing horizontal average of a field.
Oceananigans.Diagnostics.HorizontalAverage
— MethodHorizontalAverage(model, field; frequency=nothing, interval=nothing, return_type=Array)
Construct a HorizontalAverage
of field
.
After the horizontal average is computed it will be stored in the result
property.
The HorizontalAverage
can be used as a callable object that computes and returns the horizontal average.
A frequency
or interval
(or both) can be passed to indicate how often to run this diagnostic if it is part of model.diagnostics
. frequency
is a number of iterations while interval
is a time interval in units of model.clock.time
.
A return_type
can be used to specify the type returned when the HorizontalAverage
is used as a callable object. The default return_type=Array
is useful when running a GPU model and you want to save the output to disk by passing it to an output writer.
Oceananigans.Diagnostics.run_diagnostic
— Methodrun_diagnostic(model, havg::HorizontalAverage{NTuple{1}})
Compute the horizontal average of havg.field
and store the result in havg.result
.
Oceananigans.Diagnostics.CFL
— TypeCFL{D, S}
An object for computing the Courant-Freidrichs-Lewy (CFL) number.
Oceananigans.Diagnostics.CFL
— MethodCFL(Δt [, timescale=Oceananigans.cell_advection_timescale])
Returns an object for computing the Courant-Freidrichs-Lewy (CFL) number associated with time step or TimeStepWizard
Δt
and timescale
.
See also AdvectiveCFL
and DiffusiveCFL
.
Oceananigans.Diagnostics.AdvectiveCFL
— MethodAdvectiveCFL(Δt)
Returns an object for computing the Courant-Freidrichs-Lewy (CFL) number associated with time step or TimeStepWizard
Δt
and the time scale for advection across a cell.
Example
julia> model = IncompressibleModel(grid=RegularCartesianGrid(size=(16, 16, 16), length=(8, 8, 8)));
julia> cfl = AdvectiveCFL(1.0);
julia> data(model.velocities.u) .= π;
julia> cfl(model)
6.283185307179586
Oceananigans.Diagnostics.DiffusiveCFL
— MethodDiffusiveCFL(Δt)
Returns an object for computing the diffusive Courant-Freidrichs-Lewy (CFL) number associated with time step or TimeStepWizard
Δt
and the time scale for diffusion across a cell associated with model.closure
.
The maximum diffusive CFL number among viscosity and all tracer diffusivities is returned.
Example
julia> model = IncompressibleModel(grid=RegularCartesianGrid(size=(16, 16, 16), length=(1, 1, 1)));
julia> dcfl = DiffusiveCFL(0.1);
julia> dcfl(model)
2.688e-5
Oceananigans.Diagnostics.FieldMaximum
— TypeFieldMaximum(mapping, field)
An object for calculating the maximum of a mapping
function applied element-wise to field
.
Examples
julia> model = IncompressibleModel(grid=RegularCartesianGrid(size=(16, 16, 16), length=(1, 1, 1)));
julia> max_abs_u = FieldMaximum(abs, model.velocities.u);
julia> max_w² = FieldMaximum(x->x^2, model.velocities.w);
Oceananigans.Diagnostics.NaNChecker
— TypeNaNChecker{F} <: AbstractDiagnostic
A diagnostic that checks for NaN
values and aborts the simulation if any are found.
Oceananigans.Diagnostics.NaNChecker
— MethodNaNChecker(model; frequency, fields)
Construct a NaNChecker
for model
. fields
should be a Dict{Symbol,Field}
. A frequency
should be passed to indicate how often to check for NaNs (in number of iterations).
Fields
Oceananigans.Fields.AbstractField
— TypeAbstractField{X, Y, Z, A, G}
Abstract supertype for fields located at (X, Y, Z)
with data stored in a container of type A
. The field is defined on a grid G
.
Oceananigans.Fields.Field
— TypeField{X, Y, Z, A, G, B} <: AbstractField{X, Y, Z, A, G}
A field defined at the location (X
, Y
, Z
), each of which can be either Cell
or Face
, and with data stored in a container of type A
(typically an array). The field is defined on a grid G
and has field boundary conditions B
.
Oceananigans.Fields.Field
— TypeField(X, Y, Z, arch, grid, [ bcs = FieldBoundaryConditions(grid, (X, Y, Z)),
data = zeros(arch, grid, (X, Y, Z)) ] )
Construct a Field
on grid
with data
on architecture arch
with boundary conditions bcs
. Each of (X, Y, Z)
is either Cell
or Face
and determines the field's location in (x, y, z)
.
Example
julia> ω = Field(Face, Face, Cell, CPU(), RegularCartesianmodel.grid)
Oceananigans.Fields.Field
— MethodField(L::Tuple, arch, grid, data, bcs)
Construct a Field
at the location defined by the 3-tuple L
, whose elements are Cell
or Face
.
Oceananigans.Fields.CellField
— FunctionCellField([ FT=eltype(grid) ], arch::AbstractArchitecture, grid,
[ bcs = TracerBoundaryConditions(grid),
data = zeros(FT, arch, grid, (Cell, Cell, Cell) ] )
Return a Field{Cell, Cell, Cell}
on architecture arch
and grid
containing data
with field boundary conditions bcs
.
Oceananigans.Fields.XFaceField
— FunctionXFaceField([ FT=eltype(grid) ], arch::AbstractArchitecture, grid,
[ bcs = UVelocityBoundaryConditions(grid),
data = zeros(FT, arch, grid, (Face, Cell, Cell) ] )
Return a Field{Face, Cell, Cell}
on architecture arch
and grid
containing data
with field boundary conditions bcs
.
Oceananigans.Fields.YFaceField
— FunctionYFaceField([ FT=eltype(grid) ], arch::AbstractArchitecture, grid,
[ bcs = VVelocityBoundaryConditions(grid),
data = zeros(FT, arch, grid, (Cell, Face, Cell)) ] )
Return a Field{Cell, Face, Cell}
on architecture arch
and grid
containing data
with field boundary conditions bcs
.
Oceananigans.Fields.ZFaceField
— FunctionZFaceField([ FT=eltype(grid) ], arch::AbstractArchitecture, grid,
[ bcs = WVelocityBoundaryConditions(grid),
data = zeros(FT, arch, grid, (Cell, Cell, Face)) ] )
Return a Field{Cell, Cell, Face}
on architecture arch
and grid
containing data
with field boundary conditions bcs
.
Oceananigans.Fields.data
— MethodReturns f.data
for f::Field
or f
for `f::AbstractArray.
Oceananigans.Fields.interior
— MethodReturns a view of f
that excludes halo points.
Oceananigans.Fields.interiorparent
— MethodReturns a reference (not a view) to the interior points of field.data.parent.
Oceananigans.Fields.location
— MethodReturns the location (X, Y, Z)
of an AbstractField{X, Y, Z}
.
Oceananigans.Fields.set!
— Methodset!(model; kwargs...)
Set velocity and tracer fields of model
. The keyword arguments kwargs...
take the form name=data
, where name
refers to one of the fields of model.velocities
or model.tracers
, and the data
may be an array, a function with arguments (x, y, z)
, or any data type for which a set!(ϕ::AbstractField, data)
function exists.
Example
model = IncompressibleModel(grid=RegularCartesianGrid(size=(32, 32, 32), length=(1, 1, 1))
# Set u to a parabolic function of z, v to random numbers damped
# at top and bottom, and T to some silly array of half zeros,
# half random numbers.
u₀(x, y, z) = z/model.grid.Lz * (1 + z/model.grid.Lz)
v₀(x, y, z) = 1e-3 * rand() * u₀(x, y, z)
T₀ = rand(size(model.grid)...)
T₀[T₀ .< 0.5] .= 0
set!(model, u=u₀, v=v₀, T=T₀)
Oceananigans.Fields.set!
— MethodSet the CPU field u
to the array v
.
Oceananigans.Fields.set!
— MethodSet the CPU field u
data to the function f(x, y, z)
.
Forcing
Oceananigans.Forcing.SimpleForcing
— TypeSimpleForcing{X, Y, Z, F, P}
Callable object for specifying 'simple' forcings of x, y, z, t
and optionally parameters
of type P
at location X, Y, Z
.
Oceananigans.Forcing.SimpleForcing
— MethodSimpleForcing([location=(Cell, Cell, Cell),] forcing; parameters=nothing)
Construct forcing for a field at location
using forcing::Function
, and optionally with parameters
. If parameters=nothing
, forcing
must have the signature
`forcing(x, y, z, t)`;
otherwise it must have the signature
`forcing(x, y, z, t, parameters)`.
Examples
julia> const a = 2.1
julia> fun_forcing(x, y, z, t) = a * exp(z) * cos(t)
julia> u_forcing = SimpleForcing(fun_forcing)
julia> parameterized_forcing(x, y, z, t, p) = p.μ * exp(z/p.λ) * cos(p.ω*t)
julia> v_forcing = SimpleForcing(parameterized_forcing, parameters=(μ=42, λ=0.1, ω=π))
Oceananigans.Forcing.ModelForcing
— MethodModelForcing(; u=zeroforcing, v=zeroforcing, w=zeroforcing, tracer_forcings...)
Return a named tuple of forcing functions for each solution field.
Example
julia> u_forcing = SimpleForcing((x, y, z, t) -> exp(z) * cos(t))
julia> model = IncompressibleModel(forcing=ModelForcing(u=u_forcing))
Grids
Oceananigans.Grids.AbstractGrid
— TypeAbstractGrid{FT, TX, TY, TZ}
Abstract supertype for grids with elements of type FT
and topology {TX, TY, TZ}
.
Oceananigans.Grids.AbstractTopology
— TypeAbstractTopology
Abstract supertype for grid topologies.
Oceananigans.Grids.Bounded
— TypeBounded
Grid topology for bounded dimensions. These could be wall-bounded dimensions or dimensions
Oceananigans.Grids.Cell
— TypeCell
A type describing the location at the center of a grid cell.
Oceananigans.Grids.Face
— TypeFace
A type describing the location at the face of a grid cell.
Oceananigans.Grids.Flat
— TypeFlat
Grid topology for flat dimensions, generally with one grid point, along which the solution is uniform and does not vary.
Oceananigans.Grids.Periodic
— TypePeriodic
Grid topology for periodic dimensions.
Oceananigans.Grids.nodes
— Methodnodes(loc, grid)
Returns a 3-tuple of views over the interior nodes at the locations in loc
in x, y, z
.
See xnodes
, ynodes
, and znodes
.
Oceananigans.Grids.xnodes
— Methodxnodes(loc, grid)
Returns a view over the interior loc=Cell
or loc=Facenodes on
gridin the x-direction. For
Boundeddirections,
Face` nodes include the boundary points.
See znodes
for examples.
Oceananigans.Grids.ynodes
— Methodynodes(loc, grid)
Returns a view over the interior loc=Cell
or loc=Facenodes on
gridin the y-direction. For
Boundeddirections,
Face` nodes include the boundary points.
See znodes
for examples.
Oceananigans.Grids.znodes
— Methodznodes(loc, grid)
Returns a view over the interior loc=Cell
or loc=Facenodes on
gridin the z-direction. For
Boundeddirections,
Face` nodes include the boundary points.
Examples
julia> using Oceananigans, Oceananigans.Grids
julia> horz_periodic_grid = RegularCartesianGrid(size=(3, 3, 3), extent=(2π, 2π, 1),
topology=(Periodic, Periodic, Bounded));
julia> zC = znodes(Cell, horz_periodic_grid)
1×1×3 view(OffsetArray(reshape(::StepRangeLen{Float64,Base.TwicePrecision{Float64},Base.TwicePrecision{Float64}}, 1, 1, 5), 1:1, 1:1, 0:4), :, :, 1:3) with eltype Float64 with indices 1:1×1:1×Base.OneTo(3):
[:, :, 1] =
-0.8333333333333331
[:, :, 2] =
-0.4999999999999999
[:, :, 3] =
-0.16666666666666652
julia> zF = znodes(Face, horz_periodic_grid)
1×1×4 view(OffsetArray(reshape(::StepRangeLen{Float64,Base.TwicePrecision{Float64},Base.TwicePrecision{Float64}}, 1, 1, 6), 1:1, 1:1, 0:5), :, :, 1:4) with eltype Float64 with indices 1:1×1:1×Base.OneTo(4):
[:, :, 1] =
-1.0
[:, :, 2] =
-0.6666666666666666
[:, :, 3] =
-0.33333333333333337
[:, :, 4] =
-4.44089209850063e-17
Oceananigans.Grids.RegularCartesianGrid
— TypeRegularCartesianGrid{FT, TX, TY, TZ, R} <: AbstractGrid{FT, TX, TY, TZ}
A Cartesian grid with with constant grid spacings Δx
, Δy
, and Δz
between cell centers and cell faces, elements of type FT
, topology {TX, TY, TZ}
, and coordinate ranges of type R
.
Oceananigans.Grids.RegularCartesianGrid
— TypeRegularCartesianGrid([FT=Float64]; size,
extent = nothing, x = nothing, y = nothing, z = nothing,
topology = (Periodic, Periodic, Bounded), halo = (1, 1, 1))
Creates a RegularCartesianGrid
with size = (Nx, Ny, Nz)
grid points.
Keyword arguments
size
(required): A 3-tuple(Nx, Ny, Nz)
prescribing the number of grid points inx, y, z
extent
: A 3-tuple(Lx, Ly, Lz)
prescribing the physical extent of the grid. The origin is the oceanic default(0, 0, -Lz)
.x
,y
, andz
: Each ofx, y, z
are 2-tuples that specify the end points of the domain in their respect directions.
Note: Either extent
, or all of x
, y
, and z
must be specified.
topology
: A 3-tuple(Tx, Ty, Tz)
specifying the topology of the domain.Tx
,Ty
, andTz
specify whether thex
-,y
-, andz
directions arePeriodic
,Bounded
, orFlat
. In aFlat
direction, derivatives are zero. The default is(Periodic, Periodic, Bounded)
.halo
: A 3-tuple of integers that specifies the size of the halo region of cells surrounding the physical interior inx
,y
, andz
.
The physical extent of the domain can be specified via x
, y
, and z
keyword arguments indicating the left and right endpoints of each dimensions, e.g. x=(-π, π)
or via the extent
argument, e.g. extent=(Lx, Ly, Lz)
which specifies the extent of each dimension in which case 0 ≤ x ≤ Lx, 0 ≤ y ≤ Ly, and -Lz ≤ z ≤ 0.
A grid topology may be specified via a tuple assigning one of Periodic
, Bounded, and
Flatto each dimension. By default, a horizontally periodic grid topology
(Periodic, Periodic, Flat)` is assumed.
Constants are stored using floating point values of type FT
. By default this is Float64
. Make sure to specify the desired FT
if not using Float64
.
Grid properties
(Nx, Ny, Nz)::Int
: Number of physical points in the (x, y, z)-direction(Hx, Hy, Hz)::Int
: Number of halo points in the (x, y, z)-direction(Lx, Ly, Lz)::FT
: Physical extent of the grid in the (x, y, z)-direction(Δx, Δy, Δz)::FT
: Cell width in the (x, y, z)-direction(xC, yC, zC)
: (x, y, z) coordinates of cell centers, reshaped for broadcasting.(xF, yF, zF)
: (x, y, z) coordinates of cell faces, rehsaped for broadcasting.
Examples
julia> grid = RegularCartesianGrid(size=(32, 32, 32), extent=(1, 2, 3))
RegularCartesianGrid{Float64}
domain: x ∈ [0.0, 1.0], y ∈ [0.0, 2.0], z ∈ [0.0, -3.0]
resolution (Nx, Ny, Nz) = (32, 32, 32)
halo size (Hx, Hy, Hz) = (1, 1, 1)
grid spacing (Δx, Δy, Δz) = (0.03125, 0.0625, 0.09375)
julia> grid = RegularCartesianGrid(Float32; size=(32, 32, 16), x=(0, 8), y=(-10, 10), z=(-π, π))
RegularCartesianGrid{Float32}
domain: x ∈ [0.0, 8.0], y ∈ [-10.0, 10.0], z ∈ [3.141592653589793, -3.141592653589793]
resolution (Nx, Ny, Nz) = (32, 32, 16)
halo size (Hx, Hy, Hz) = (1, 1, 1)
grid spacing (Δx, Δy, Δz) = (0.25f0, 0.625f0, 0.3926991f0)
Models
Oceananigans.Models.state
— Methodstate(model)
Returns a NamedTuple
with fields velocities, tracers, diffusivities, tendencies
corresponding to NamedTuple
s of OffsetArray
s that reference each of the field's data.
Oceananigans.Models.Clock
— TypeClock{T<:Number}
Clock{T}(time, iteration)
Keeps track of the current time
and iteration
number. The time::T
can be either a number of a DateTime
object.
Oceananigans.Models.NonDimensionalModel
— MethodNonDimensionalModel(; N, L, Re, Pr=0.7, Ro=Inf, float_type=Float64, kwargs...)
Construct a "Non-dimensional" Model
with resolution N
, domain extent L
, precision float_type
, and the four non-dimensional numbers:
* `Re = U λ / ν` (Reynolds number)
* `Pr = U λ / κ` (Prandtl number)
* `Ro = U / f λ` (Rossby number)
for characteristic velocity scale U
, length-scale λ
, viscosity ν
, tracer diffusivity κ
, and Coriolis parameter f
. Buoyancy is scaled with λ U²
, so that the Richardson number is Ri=B
, where B
is a non-dimensional buoyancy scale set by the user via initial conditions or forcing.
Note that N
, L
, and Re
are required.
Additional kwargs
are passed to the regular IncompressibleModel
constructor.
Output writers
Oceananigans.OutputWriters.FieldOutput
— TypeFieldOutput([return_type=Array], field)
Returns a FieldOutput
type intended for use with the JLD2OutputWriter
. Calling FieldOutput(model)
returns return_type(field.data.parent)
.
Oceananigans.OutputWriters.JLD2OutputWriter
— TypeJLD2OutputWriter{F, I, O, IF, IN, KW} <: AbstractOutputWriter
An output writer for writing to JLD2 files.
Oceananigans.OutputWriters.JLD2OutputWriter
— MethodJLD2OutputWriter(model, outputs; interval=nothing, frequency=nothing, dir=".",
prefix="", init=noinit, including=[:grid, :coriolis, :buoyancy, :closure],
part=1, max_filesize=Inf, force=false, async=false, verbose=false, jld2_kw=Dict{Symbol, Any}())
Construct a JLD2OutputWriter
that writes label, func
pairs in outputs
(which can be a Dict
or NamedTuple
) to a JLD2 file, where label
is a symbol that labels the output and func
is a function of the form func(model)
that returns the data to be saved.
Keyword arguments
frequency::Int
: Save output everyn
model iterations.interval::Int
: Save output everyt
units of model clock time.dir::String
: Directory to save output to. Default: "." (current working directory).prefix::String
: Descriptive filename prefixed to all output files. Default: "".init::Function
: A function of the forminit(file, model)
that runs when a JLD2 output file is initialized. Default:noinit(args...) = nothing
.including::Array
: List of model properties to save with every file. By default, the grid, equation of state, Coriolis parameters, buoyancy parameters, and turbulence closure parameters are saved.part::Int
: The starting part number used ifmax_filesize
is finite. Default: 1.max_filesize::Int
: The writer will stop writing to the output file once the file size exceedsmax_filesize
, and write to a new one with a consistent naming scheme ending inpart1
,part2
, etc. Defaults toInf
.force::Bool
: Remove existing files if their filenames conflict. Default:false
.async::Bool
: Write output asynchronously. Default:false
.verbose::Bool
: Log what the output writer is doing with statistics on compute/write times and file sizes. Default:false
.jld2_kw::Dict
: Dict of kwargs to be passed tojldopen
when data is written.
Oceananigans.OutputWriters.FieldOutputs
— MethodFieldOutputs(fields)
Returns a dictionary of FieldOutput
objects with key, value pairs corresponding to each name and value in the NamedTuple
fields
. Intended for use with JLD2OutputWriter
.
Examples
julia> output_writer = JLD2OutputWriter(model, FieldOutputs(model.velocities), frequency=1);
julia> keys(output_writer.outputs)
Base.KeySet for a Dict{Symbol,FieldOutput{UnionAll,F} where F} with 3 entries. Keys:
:w
:v
:u
Oceananigans.OutputWriters.NetCDFOutputWriter
— TypeNetCDFOutputWriter <: AbstractOutputWriter
An output writer for writing to NetCDF files.
Oceananigans.OutputWriters.write_grid_and_attributes
— Methodwrite_grid_and_attributes(model; filename="grid.nc", mode="c",
compression=0, attributes=Dict(), slice_kw...)
Writes grid and global attributes
to filename
. By default writes information to a standalone grid.nc
file.
Keyword arguments
filename
: File name to be saved under.mode
: NetCDF file is opened in either clobber ("c") or append ("a") mode. Default: "c".compression
: Defines the compression level of data from 0-9. Default: 0.attributes
: Global attributes. Default: Dict().
Oceananigans.OutputWriters.write_output
— Methodwrite_output(model, OutputWriter)
Writes output to the netcdf file at specified intervals. Increments the time
dimension every time an output is written to the file.
Oceananigans.OutputWriters.Checkpointer
— TypeCheckpointer{I, T, P, A} <: AbstractOutputWriter
An output writer for checkpointing models to a JLD2 file from which models can be restored.
Oceananigans.OutputWriters.Checkpointer
— MethodCheckpointer(model; frequency=nothing, interval=nothing, dir=".",
prefix="checkpoint", force=false, verbose=false,
properties = [:architecture, :boundary_conditions, :grid, :clock, :coriolis,
:buoyancy, :closure, :velocities, :tracers, :timestepper])
Construct a Checkpointer
that checkpoints the model to a JLD2 file every so often as specified by frequency
or interval
. The model.clock.iteration
is included in the filename to distinguish between multiple checkpoint files.
Note that extra model properties
can be safely specified, but removing crucial properties such as :velocities
will make restoring from the checkpoint impossible.
The checkpoint file is generated by serializing model properties to JLD2. However, functions cannot be serialized to disk (at least not with JLD2). So if a model property contains a reference somewhere in its hierarchy it will not be included in the checkpoint file (and you will have to manually restore them).
Keyword arguments
frequency::Int
: Save output everyn
model iterations.interval::Int
: Save output everyt
units of model clock time.dir::String
: Directory to save output to. Default: "." (current working directory).prefix::String
: Descriptive filename prefixed to all output files. Default: "checkpoint".force::Bool
: Remove existing files if their filenames conflict. Default:false
.verbose::Bool
: Log what the output writer is doing with statistics on compute/write times and file sizes. Default:false
.properties::Array
: List of model properties to checkpoint.
Oceananigans.OutputWriters.restore_from_checkpoint
— Methodrestore_from_checkpoint(filepath; kwargs=Dict())
Restore a model from the checkpoint file stored at filepath
. kwargs
can be passed to the model constructor, which can be especially useful if you need to manually restore forcing functions or boundary conditions that rely on functions.
Time steppers
Oceananigans.TimeSteppers.AdamsBashforthTimeStepper
— TypeAdamsBashforthTimeStepper(float_type, arch, grid, tracers, χ=0.125;
Gⁿ = TendencyFields(arch, grid, tracers),
G⁻ = TendencyFields(arch, grid, tracers))
Return an AdamsBashforthTimeStepper object with tendency fields on arch
and grid
with AB2 parameter χ
. The tendency fields can be specified via optional kwargs.
Oceananigans.TimeSteppers.time_step!
— Methodtime_step!(model::IncompressibleModel{<:AdamsBashforthTimeStepper}, Δt; euler=false)
Step forward model
one time step Δt
with a 2nd-order Adams-Bashforth method and pressure-correction substep. Setting euler=true
will take a forward Euler time step.
Simulations
Oceananigans.Simulations.Simulation
— MethodSimulation(model; Δt,
stop_criteria = Function[iteration_limit_exceeded, stop_time_exceeded, wall_time_limit_exceeded],
stop_iteration = Inf,
stop_time = Inf,
wall_time_limit = Inf,
diagnostics = OrderedDict{Symbol, AbstractDiagnostic}(),
output_writers = OrderedDict{Symbol, AbstractOutputWriter}(),
progress = nothing,
progress_frequency = 1,
parameters = nothing)
Construct an Oceananigans.jl Simulation
for a model
with time step Δt
.
Keyword arguments
Δt
: Required keyword argument specifying the simulation time step. Can be aNumber
for constant time steps or aTimeStepWizard
for adaptive time-stepping.stop_criteria
: A list of functions or callable objects (each taking a single argument, thesimulation
). If any of the functions returntrue
when the stop criteria is evaluated the simulation will stop.stop_iteration
: Stop the simulation after this many iterations.stop_time
: Stop the simulation once this much model clock time has passed.wall_time_limit
: Stop the simulation if it's been running for longer than this many seconds of wall clock time.progress
: A function with a single argument, thesimulation
. Will be called everyprogress_frequency
iterations. Useful for logging simulation health.progress_frequency
: How often to update the time step, check stop criteria, and callprogress
function (in number of iterations).parameters
: Parameters that can be accessed in theprogress
function.
Oceananigans.Simulations.run!
— Methodrun!(simulation)
Run a simulation
until one of the stop criteria evaluates to true. The simulation will then stop.
Tubrulence closures
Oceananigans.TurbulenceClosures.AnisotropicMinimumDissipation
— TypeAnisotropicMinimumDissipation
An alias for VerstappenAnisotropicMinimumDissipation
.
Oceananigans.TurbulenceClosures.ConstantSmagorinsky
— TypeConstantSmagorinsky
An alias for SmagorinskyLilly
.
Oceananigans.TurbulenceClosures.IsotropicViscosity
— TypeIsotropicViscosity{FT} <: TurbulenceClosure{FT}
Abstract supertype for turbulence closures that are defined by an isotropic viscosity and isotropic diffusivities with model parameters stored as properties of type FT
.
Oceananigans.TurbulenceClosures.∂ⱼ_2ν_Σ₁ⱼ
— Method∂ⱼ_2ν_Σ₁ⱼ(i, j, k, grid, closure, U, diffusivities)
Return the $x$-component of the turbulent diffusive flux divergence:
∂x(2 ν Σ₁₁) + ∂y(2 ν Σ₁₁) + ∂z(2 ν Σ₁₁)
at the location fcc
.
Oceananigans.TurbulenceClosures.∂ⱼ_2ν_Σ₂ⱼ
— Method∂ⱼ_2ν_Σ₂ⱼ(i, j, k, grid, closure, U, diffusivities)
Return the $y$-component of the turbulent diffusive flux divergence:
∂x(2 ν Σ₂₁) + ∂y(2 ν Σ₂₂) + ∂z(2 ν Σ₂₂)
at the location ccf
.
Oceananigans.TurbulenceClosures.∂ⱼ_2ν_Σ₃ⱼ
— Method∂ⱼ_2ν_Σ₃ⱼ(i, j, k, grid, closure, diffusivities)
Return the $z$-component of the turbulent diffusive flux divergence:
∂x(2 ν Σ₃₁) + ∂y(2 ν Σ₃₂) + ∂z(2 ν Σ₃₃)
at the location ccf
.
Oceananigans.TurbulenceClosures.AnisotropicBiharmonicDiffusivity
— TypeAnisotropicBiharmonicDiffusivity{FT, KH, KV}
Parameters for anisotropic biharmonic diffusivity models.
Oceananigans.TurbulenceClosures.AnisotropicBiharmonicDiffusivity
— TypeAnisotropicBiharmonicDiffusivity(; νh, νv, κh, κv)
Returns parameters for a fourth-order, anisotropic biharmonic diffusivity closure with constant horizontal and vertical biharmonic viscosities νh
, νv
and constant horizontal and vertical tracer biharmonic diffusivities κh
, κv
. κh
and κv
may be NamedTuple
s with fields corresponding to each tracer, or a single number to be a applied to all tracers. The tracer flux divergence associated with an anisotropic biharmonic diffusivity is, for example
Oceananigans.TurbulenceClosures.SmagorinskyLilly
— TypeSmagorinskyLilly{FT} <: AbstractSmagorinsky{FT}
Parameters for the Smagorinsky-Lilly turbulence closure.
Oceananigans.TurbulenceClosures.SmagorinskyLilly
— TypeSmagorinskyLilly([FT=Float64;] C=0.23, Pr=1, ν=1.05e-6, κ=1.46e-7)
Return a SmagorinskyLilly
type associated with the turbulence closure proposed by Lilly (1962) and Smagorinsky (1958, 1963), which has an eddy viscosity of the form
`νₑ = (C * Δᶠ)² * √(2Σ²) * √(1 - Cb * N² / Σ²) + ν`,
and an eddy diffusivity of the form
`κₑ = (νₑ - ν) / Pr + κ`
where Δᶠ
is the filter width, Σ² = ΣᵢⱼΣᵢⱼ
is the double dot product of the strain tensor Σᵢⱼ
, Pr
is the turbulent Prandtl number, and N²
is the total buoyancy gradient, and Cb
is a constant the multiplies the Richardson number modification to the eddy viscosity.
Keyword arguments
- `C` : Model constant
- `Cb` : Buoyancy term multipler (`Cb = 0` turns it off, `Cb ≠ 0` turns it on.
Typically `Cb=1/Pr`.)
- `Pr` : Turbulent Prandtl numbers for each tracer. Either a constant applied to every
tracer, or a `NamedTuple` with fields for each tracer individually.
- `ν` : Constant background viscosity for momentum
- `κ` : Constant background diffusivity for tracer. Can either be a single number
applied to all tracers, or `NamedTuple` of diffusivities corresponding to each
tracer.
References
Smagorinsky, J. "On the numerical integration of the primitive equations of motion for baroclinic flow in a closed region." Monthly Weather Review (1958)
Lilly, D. K. "On the numerical simulation of buoyant convection." Tellus (1962)
Smagorinsky, J. "General circulation experiments with the primitive equations: I. The basic experiment." Monthly weather review (1963)
Oceananigans.TurbulenceClosures.∇_κ_∇c
— Method∇_κ_∇c(i, j, k, grid, c, closure, diffusivities)
Return the diffusive flux divergence ∇ ⋅ (κ ∇ c)
for the turbulence closure
, where c
is an array of scalar data located at cell centers.
Oceananigans.TurbulenceClosures.ConstantIsotropicDiffusivity
— TypeConstantIsotropicDiffusivity{FT, K}
Parameters for constant isotropic diffusivity models.
Oceananigans.TurbulenceClosures.ConstantIsotropicDiffusivity
— TypeConstantIsotropicDiffusivity([FT=Float64;] ν, κ)
Returns parameters for a constant isotropic diffusivity model with constant viscosity ν
and constant thermal diffusivities κ
for each tracer field in tracers
ν
and the fields of κ
may represent molecular diffusivities in cases that all flow features are explicitly resovled, or turbulent eddy diffusivities that model the effect of unresolved, subgrid-scale turbulence. κ
may be a NamedTuple
with fields corresponding to each tracer, or a single number to be a applied to all tracers.
By default, a molecular viscosity of ν = 1.05×10⁻⁶
m² s⁻¹ and a molecular thermal diffusivity of κ = 1.46×10⁻⁷
m² s⁻¹ is used for each tracer. These molecular values are the approximate viscosity and thermal diffusivity for seawater at 20°C and 35 psu, according to Sharqawy et al., "Thermophysical properties of seawater: A review of existing correlations and data" (2010).
Oceananigans.TurbulenceClosures.VerstappenAnisotropicMinimumDissipation
— TypeVerstappenAnisotropicMinimumDissipation{FT} <: AbstractAnisotropicMinimumDissipation{FT}
Parameters for the anisotropic minimum dissipation large eddy simulation model proposed by Verstappen (2018) and described by Vreugdenhil & Taylor (2018).
Oceananigans.TurbulenceClosures.VerstappenAnisotropicMinimumDissipation
— TypeVerstappenAnisotropicMinimumDissipation(FT=Float64; C=1/12, Cν=nothing, Cκ=nothing,
Cb=0.0, ν=ν₀, κ=κ₀)
Returns parameters of type FT
for the VerstappenAnisotropicMinimumDissipation
turbulence closure.
Keyword arguments
- `C` : Poincaré constant for both eddy viscosity and eddy diffusivities. `C` is overridden
for eddy viscosity or eddy diffusivity if `Cν` or `Cκ` are set, respecitvely.
- `Cν` : Poincaré constant for momentum eddy viscosity.
- `Cκ` : Poincaré constant for tracer eddy diffusivities. If one number or function, the same
number or function is applied to all tracers. If a `NamedTuple`, it must possess
a field specifying the Poncaré constant for every tracer.
- `Cb` : Buoyancy modification multiplier (`Cb = 0` turns it off, `Cb = 1` turns it on)
- `ν` : Constant background viscosity for momentum.
- `κ` : Constant background diffusivity for tracer. If a single number, the same background
diffusivity is applied to all tracers. If a `NamedTuple`, it must possess a field
specifying a background diffusivity for every tracer.
By default: C = Cν = Cκ
= 1/12, which is appropriate for a finite-volume method employing a second-order advection scheme, Cb
= 0, which terms off the buoyancy modification term, the molecular viscosity of seawater at 20 deg C and 35 psu is used for ν
, and the molecular diffusivity of heat in seawater at 20 deg C and 35 psu is used for κ
.
Cν
or Cκ
may be constant numbers, or functions of x, y, z
.
Example
julia> prettydiffusiveclosure = AnisotropicMinimumDissipation(C=1/2) VerstappenAnisotropicMinimumDissipation{Float64} turbulence closure with: Poincaré constant for momentum eddy viscosity Cν: 0.5 Poincaré constant for tracer(s) eddy diffusivit(ies) Cκ: 0.5 Buoyancy modification multiplier Cb: 0.0 Background diffusivit(ies) for tracer(s), κ: 1.46e-7 Background kinematic viscosity for momentum, ν: 1.05e-6
julia> const Δz = 0.5; # grid resolution at surface
julia> surfaceenhancedtracerC(x, y, z) = 1/12 * (1 + exp((z + Δz/2) / 8Δz)) surfaceenhancedtracerC (generic function with 1 method)
julia> fancyclosure = AnisotropicMinimumDissipation(Cκ=surfaceenhancedtracerC) VerstappenAnisotropicMinimumDissipation{Float64} turbulence closure with: Poincaré constant for momentum eddy viscosity Cν: 0.08333333333333333 Poincaré constant for tracer(s) eddy diffusivit(ies) Cκ: surfaceenhancedtracer_C Buoyancy modification multiplier Cb: 0.0 Background diffusivit(ies) for tracer(s), κ: 1.46e-7 Background kinematic viscosity for momentum, ν: 1.05e-6
julia> tracerspecificclosure = AnisotropicMinimumDissipation(Cκ=(c₁=1/12, c₂=1/6)) VerstappenAnisotropicMinimumDissipation{Float64} turbulence closure with: Poincaré constant for momentum eddy viscosity Cν: 0.08333333333333333 Poincaré constant for tracer(s) eddy diffusivit(ies) Cκ: (c₁ = 0.08333333333333333, c₂ = 0.16666666666666666) Buoyancy modification multiplier Cb: 0.0 Background diffusivit(ies) for tracer(s), κ: 1.46e-7 Background kinematic viscosity for momentum, ν: 1.05e-6
References
Vreugdenhil C., and Taylor J. (2018), "Large-eddy simulations of stratified plane Couette flow using the anisotropic minimum-dissipation model", Physics of Fluids 30, 085104.
Verstappen, R. (2018), "How much eddy dissipation is needed to counterbalance the nonlinear production of small, unresolved scales in a large-eddy simulation of turbulence?", Computers & Fluids 176, pp. 276-284.
Oceananigans.TurbulenceClosures.∇_κ_∇c
— Method∇_κ_∇c(i, j, k, grid, c, tracer_index, closure, diffusivities)
Return the diffusive flux divergence ∇ ⋅ (κ ∇ c)
for the turbulence closure
, where c
is an array of scalar data located at cell centers.
Oceananigans.TurbulenceClosures.BlasiusSmagorinsky
— TypeBlasiusSmagorinsky{ML, FT}
Parameters for the version of the Smagorinsky closure used in the UK Met Office code Blasius, according to Polton and Belcher (2007).
Oceananigans.TurbulenceClosures.BlasiusSmagorinsky
— TypeBlasiusSmagorinsky(FT=Float64; Pr=1.0, ν=1.05e-6, κ=1.46e-7)
Returns a BlasiusSmagorinsky
closure object of type FT
.
Keyword arguments
- `Pr` : Turbulent Prandtl numbers for each tracer. Either a constant applied to every
tracer, or a `NamedTuple` with fields for each tracer individually.
- `ν` : Constant background viscosity for momentum
- `κ` : Constant background diffusivity for tracer. Can either be a single number
applied to all tracers, or `NamedTuple` of diffusivities corresponding to each
tracer.
References
Polton, J. A., and Belcher, S. E. (2007), "Langmuir turbulence and deeply penetrating jets in an unstratified mixed layer." Journal of Geophysical Research: Oceans.
Oceananigans.TurbulenceClosures.ConstantAnisotropicDiffusivity
— TypeConstantAnisotropicDiffusivity{FT, KH, KV}
Parameters for constant anisotropic diffusivity models.
Oceananigans.TurbulenceClosures.ConstantAnisotropicDiffusivity
— TypeConstantAnisotropicDiffusivity(; νh, νv, κh, κv)
Returns parameters for a constant anisotropic diffusivity closure with constant horizontal and vertical viscosities νh
, νv
and constant horizontal and vertical tracer diffusivities κh
, κv
. κh
and κv
may be NamedTuple
s with fields corresponding to each tracer, or a single number to be a applied to all tracers.
By default, a viscosity of ν = 1.05×10⁻⁶
m² s⁻¹ is used for both the horizontal and vertical viscosity, and a diffusivity of κ = 1.46×10⁻⁷
m² s⁻¹ is used for the horizontal and vertical diffusivities applied to every tracer. These values are the approximate viscosity and thermal diffusivity for seawater at 20°C and 35 psu, according to Sharqawy et al., "Thermophysical properties of seawater: A review of existing correlations and data" (2010).
Oceananigans.TurbulenceClosures.RozemaAnisotropicMinimumDissipation
— TypeRozemaAnisotropicMinimumDissipation(FT=Float64; C=0.33, ν=1.05e-6, κ=1.46e-7)
Returns a RozemaAnisotropicMinimumDissipation
closure object of type FT
with
* `C` : Poincaré constant
* `ν` : 'molecular' background viscosity
* `κ` : 'molecular' background diffusivity for each tracer
See Rozema et al., " (2015)
Oceananigans.TurbulenceClosures.TwoDimensionalLeith
— TypeTwoDimensionalLeith{FT} <: AbstractLeith{FT}
Parameters for the 2D Leith turbulence closure.
Oceananigans.TurbulenceClosures.TwoDimensionalLeith
— TypeTwoDimensionalLeith([FT=Float64;] C=0.3, C_Redi=1, C_GM=1)
Return a TwoDimensionalLeith
type associated with the turbulence closure proposed by Leith (1965) and Fox-Kemper & Menemenlis (2008) which has an eddy viscosity of the form
`νₑ = (C * Δᶠ)³ * √(ζ² + (∇h ∂z w)²)`
and an eddy diffusivity of the form...
where Δᶠ
is the filter width, ζ² = (∂x v - ∂y u)²
is the squared vertical vorticity, and C
is a model constant.
Keyword arguments
- `C` : Model constant
- `C_Redi` : Coefficient for down-gradient tracer diffusivity for each tracer.
Either a constant applied to every tracer, or a `NamedTuple` with fields
for each tracer individually.
- `C_GM` : Coefficient for down-gradient tracer diffusivity for each tracer.
Either a constant applied to every tracer, or a `NamedTuple` with fields
for each tracer individually.
References
Leith, C. E. (1968). "Diffusion Approximation for Two‐Dimensional Turbulence", The Physics of Fluids 11, 671. doi: 10.1063/1.1691968
Fox‐Kemper, B., & D. Menemenlis (2008), "Can large eddy simulation techniques improve mesoscale rich ocean models?", in Ocean Modeling in an Eddying Regime, Geophys. Monogr. Ser., vol. 177, pp. 319–337. doi:10.1029/177GM19
Pearson, B. et al. (2017) , "Evaluation of scale-aware subgrid mesoscale eddy models in a global eddy rich model", Ocean Modelling 115, 42-58. doi: 10.1016/j.ocemod.2017.05.007
Oceananigans.TurbulenceClosures.∇_κ_∇c
— Method∇_κ_∇c(i, j, k, grid, c, closure, diffusivities)
Return the diffusive flux divergence ∇ ⋅ (κ ∇ c)
for the turbulence closure
, where c
is an array of scalar data located at cell centers.
Utilities
Oceananigans.Utils.GiB
— ConstantGiB
A Float64
constant equal to 1024MiB
. Useful for increasing the clarity of scripts, e.g. max_filesize = 50GiB
.
Oceananigans.Utils.KiB
— ConstantKiB
A Float64
constant equal to 1024.0. Useful for increasing the clarity of scripts, e.g. max_filesize = 250KiB
.
Oceananigans.Utils.MiB
— ConstantMiB
A Float64
constant equal to 1024KiB
. Useful for increasing the clarity of scripts, e.g. max_filesize = 100MiB
.
Oceananigans.Utils.TiB
— ConstantTiB
A Float64
constant equal to 1024GiB
. Useful for increasing the clarity of scripts, e.g. max_filesize = 2TiB
.
Oceananigans.Utils.day
— Constantday
A Float64
constant equal to 24hour
. Useful for increasing the clarity of scripts, e.g. Δt = 0.5day
.
Oceananigans.Utils.hour
— Constanthour
A Float64
constant equal to 60minute
. Useful for increasing the clarity of scripts, e.g. Δt = 3hour
.
Oceananigans.Utils.kilometer
— Constantkilometer
A Float64
constant equal to 1000meter
. Useful for increasing the clarity of scripts, e.g. Lx = 250kilometer
.
Oceananigans.Utils.meter
— Constantmeter
A Float64
constant equal to 1.0. Useful for increasing the clarity of scripts, e.g. Lx = 100meter
.
Oceananigans.Utils.minute
— Constantminute
A Float64
constant equal to 60second
. Useful for increasing the clarity of scripts, e.g. Δt = 15minute
.
Oceananigans.Utils.second
— Constantsecond
A Float64
constant equal to 1.0. Useful for increasing the clarity of scripts, e.g. Δt = 1second
.
Oceananigans.Utils.prettytime
— Methodprettytime(t)
Convert a floating point value t
representing an amount of time in seconds to a more human-friendly formatted string with three decimal places. Depending on the value of t
the string will be formatted to show t
in nanoseconds (ns), microseconds (μs), milliseconds (ms), seconds (s), minutes (min), hours (hr), or days (day).
Oceananigans.Utils.pretty_filesize
— Functionpretty_filesize(s, suffix="B")
Convert a floating point value s
representing a file size to a more human-friendly formatted string with one decimal places with a suffix
defaulting to "B". Depending on the value of s
the string will be formatted to show s
using an SI prefix from bytes, kiB (1024 bytes), MiB (1024² bytes), and so on up to YiB (1024⁸ bytes).
Oceananigans.Utils.update_Δt!
— Methodupdate_Δt!(wizard, model)
Compute wizard.Δt
given the velocities and diffusivities of model
, and the parameters of wizard
.
Oceananigans.Utils.cell_advection_timescale
— MethodReturns the time-scale for advection on a regular grid across a single grid cell.
Oceananigans.Utils.validate_interval
— Methodvalidate_interval(frequency, interval)
Ensure that frequency and interval are not both nothing
.
Oceananigans.Utils.with_tracers
— Methodwith_tracers(tracer_names, initial_tuple, tracer_default)
Create a tuple corresponding to the solution variables u
, v
, w
, and tracer_names
. initial_tuple
is a NamedTuple
that at least has fields u
, v
, and w
, and may have some fields corresponding to the names in tracer_names
. tracer_default
is a function that produces a default tuple value for each tracer if not included in initial_tuple
.
Abstract operations
Oceananigans.AbstractOperations.@unary
— Macro@unary op1 op2 op3...
Turn each unary function in the list (op1, op2, op3...)
into a unary operator on Oceananigans.Fields
for use in AbstractOperations
.
Note: a unary function is a function with one argument: for example, sin(x)
is a unary function.
Also note: a unary function in Base
must be imported to be extended: use import Base: op; @unary op
.
Example
julia> squareit(x) = x^2 squareit (generic function with 1 method)
julia> @unary squareit 7-element Array{Any,1}: :sqrt :sin :cos :exp :tanh :- :squareit
julia> c = Field(Cell, Cell, Cell, CPU(), RegularCartesianGrid((1, 1, 16), (1, 1, 1)));
julia> square_it(c) UnaryOperation at (Cell, Cell, Cell) ├── grid: RegularCartesianGrid{Float64,StepRangeLen{Float64,Base.TwicePrecision{Float64},Base.TwicePrecision{Float64}}} │ ├── size: (1, 1, 16) │ └── domain: x ∈ [0.0, 1.0], y ∈ [0.0, 1.0], z ∈ [0.0, -1.0] └── tree:
square_it at (Cell, Cell, Cell) via identity └── OffsetArrays.OffsetArray{Float64,3,Array{Float64,3}}
Oceananigans.AbstractOperations.@binary
— Macro@binary op1 op2 op3...
Turn each binary function in the list (op1, op2, op3...)
into a binary operator on Oceananigans.Fields
for use in AbstractOperations
.
Note: a binary function is a function with two arguments: for example, +(x, y)
is a binary function.
Also note: a binary function in Base
must be imported to be extended: use import Base: op; @binary op
.
Example
```jldoctest julia> plusortimes(x, y) = x < 0 ? x + y : x * y plusortimes (generic function with 1 method)
julia> @binary plusortimes 6-element Array{Any,1}: :+ :- :/ :^ :* :plusortimes
julia> c, d = (Field(Cell, Cell, Cell, CPU(), RegularCartesianGrid((1, 1, 16), (1, 1, 1))) for i = 1:2);
julia> plusortimes(c, d) BinaryOperation at (Cell, Cell, Cell) ├── grid: RegularCartesianGrid{Float64,StepRangeLen{Float64,Base.TwicePrecision{Float64},Base.TwicePrecision{Float64}}} │ ├── size: (1, 1, 16) │ └── domain: x ∈ [0.0, 1.0], y ∈ [0.0, 1.0], z ∈ [0.0, -1.0] └── tree:
plusortimes at (Cell, Cell, Cell) via Oceananigans.AbstractOperations.identity ├── OffsetArrays.OffsetArray{Float64,3,Array{Float64,3}} └── OffsetArrays.OffsetArray{Float64,3,Array{Float64,3}}
Oceananigans.AbstractOperations.@multiary
— Macro@multiary op1 op2 op3...
Turn each multiary operator in the list (op1, op2, op3...)
into a multiary operator on Oceananigans.Fields
for use in AbstractOperations
.
Note that a multiary operator: * is a function with two or more arguments: for example, +(x, y, z)
is a multiary function; * must be imported to be extended if part of Base
: use import Base: op; @multiary op
; * can only be called on Oceananigans.Field
s if the "location" is noted explicitly; see example.
Example
```jldoctest julia> harmonicplus(a, b, c) = 1/3 * (1/a + 1/b + 1/c) harmonicplus(generic function with 1 method)
julia> @multiary harmonicplus 3-element Array{Any,1}: :+ :* :harmonicplus
julia> c, d, e = Tuple(Field(Cell, Cell, Cell, CPU(), RegularCartesianGrid((1, 1, 16), (1, 1, 1))) for i = 1:3);
julia> harmonic_plus(c, d, e) # this calls the original function, which in turn returns a (correct) operation tree BinaryOperation at (Cell, Cell, Cell) ├── grid: RegularCartesianGrid{Float64,StepRangeLen{Float64,Base.TwicePrecision{Float64},Base.TwicePrecision{Float64}}} │ ├── size: (1, 1, 16) │ └── domain: x ∈ [0.0, 1.0], y ∈ [0.0, 1.0], z ∈ [0.0, -1.0] └── tree:
- at (Cell, Cell, Cell) via Oceananigans.AbstractOperations.identity
├── 0.3333333333333333 └── + at (Cell, Cell, Cell) via Oceananigans.AbstractOperations.identity ├── + at (Cell, Cell, Cell) via Oceananigans.AbstractOperations.identity │ ├── / at (Cell, Cell, Cell) via Oceananigans.AbstractOperations.identity │ │ ├── 1 │ │ └── OffsetArrays.OffsetArray{Float64,3,Array{Float64,3}} │ └── / at (Cell, Cell, Cell) via Oceananigans.AbstractOperations.identity │ ├── 1 │ └── OffsetArrays.OffsetArray{Float64,3,Array{Float64,3}} └── / at (Cell, Cell, Cell) via Oceananigans.AbstractOperations.identity ├── 1 └── OffsetArrays.OffsetArray{Float64,3,Array{Float64,3}}
julia> @at (Cell, Cell, Cell) harmonic_plus(c, d, e) # this returns a MultiaryOperation
as expected MultiaryOperation at (Cell, Cell, Cell) ├── grid: RegularCartesianGrid{Float64,StepRangeLen{Float64,Base.TwicePrecision{Float64},Base.TwicePrecision{Float64}}} │ ├── size: (1, 1, 16) │ └── domain: x ∈ [0.0, 1.0], y ∈ [0.0, 1.0], z ∈ [0.0, -1.0] └── tree:
harmonic_plus at (Cell, Cell, Cell) ├── OffsetArrays.OffsetArray{Float64,3,Array{Float64,3}} ├── OffsetArrays.OffsetArray{Float64,3,Array{Float64,3}} └── OffsetArrays.OffsetArray{Float64,3,Array{Float64,3}}
Oceananigans.AbstractOperations.∂x
— MethodReturn the x-derivative function acting at (X
, Any
, Any
).
Oceananigans.AbstractOperations.∂x
— Method∂x(a::AbstractField)
Return an abstract representation of a x-derivative acting on a
.
Oceananigans.AbstractOperations.∂x
— Method∂x(L::Tuple, a::AbstractField)
Return an abstract representation of an x-derivative acting on a
followed by interpolation to L
, where L
is a 3-tuple of Face
s and Cell
s.
Oceananigans.AbstractOperations.∂y
— MethodReturn the y-derivative function acting at (Any
, Y
, Any
).
Oceananigans.AbstractOperations.∂y
— Method∂y(a::AbstractField)
Return an abstract representation of a y-derivative acting on a
.
Oceananigans.AbstractOperations.∂y
— Method∂y(L::Tuple, a::AbstractField)
Return an abstract representation of a y-derivative acting on a
followed by interpolation to L
, where L
is a 3-tuple of Face
s and Cell
s.
Oceananigans.AbstractOperations.∂z
— MethodReturn the z-derivative function acting at (Any
, Any
, Z
).
Oceananigans.AbstractOperations.∂z
— Method∂z(a::AbstractField)
Return an abstract representation of a z-derivative acting on a
.
Oceananigans.AbstractOperations.∂z
— Method∂z(L::Tuple, a::AbstractField)
Return an abstract representation of a z-derivative acting on a
followed by interpolation to L
, where L
is a 3-tuple of Face
s and Cell
s.
Oceananigans.AbstractOperations.Computation
— TypeComputation{T, R, O, G}
Represents an operation performed over the elements of a field.
Oceananigans.AbstractOperations.Computation
— Method(computation::Computation)(args...)
Performs the compute(computation)
and returns the result if isnothing(return_type)
, or the result after being converted to return_type
.
Oceananigans.AbstractOperations.Computation
— MethodComputation(operation, result; return_type=Array)
Returns a Computation
representing an operation
performed over the elements of operation.grid
and stored in result
. return_type
specifies the output type when the Computation
instances is called as a function.
Oceananigans.AbstractOperations.compute!
— Methodcompute!(computation::Computation)
Perform a computation
. The result is stored in computation.result
.
Oceananigans.AbstractOperations.@at
— Macro@at location abstract_operation
Modify the abstract_operation
so that it returns values at location
, where location
is a 3-tuple of Face
s and Cell
s.