- resizes to current fieldNames_ size and assigns everything to
false to avoid any "stickiness" if the field ordering changes
between reads.
ENH: additional debugging faOption/fvOption (#2110)
- aids tracing which sources are being used/ignored
- update code style
STYLE: rename CodedSource -> CodedFvSource
- avoid future name clashes with CodedFaSource
Please refer to the header file documentation for complete set of details.
ENH: add new fvOptions for ABL modelling
- atmAmbientTurbSource
- atmBuoyancyTurbSource
- atmCoriolisUSource
- atmLengthScaleTurbSource
- atmPlantCanopyTurbSource
- atmPlantCanopyUSource
- atmPlantCanopyTSource
- atmNutSource
ENH: add new boundary conditions for ABL modelling
with PatchFunction1 and TimeFunction1 support
- atmAlphatkWallFunction
- atmEpsilonWallFunction
- atmNutkWallFunction
- atmNutUWallFunction
- atmNutWallFunction
- atmOmegaWallFunction
- atmTurbulentHeatFluxTemperature
STYLE: change names of nutkAtmRoughWallFunction -> atmNutkWallFunction by
ensuring the bitwise backward compatibility
ENH: add new variable-scaling force computation method to actuationDiskSource
ENH: review actuationDiskSource and radialActuationDiskSource
ENH: add new function object, ObukhovLength
ENH: add new ABL tutorials/verifications
- verificationAndValidation/atmosphericModels/atmFlatTerrain
- verification with the Leipzig field experiment
- illustration of precursor/successor field mapping
- verificationAndValidation/atmosphericModels/atmForestStability
- verification with the Sweden field experiment
- update incompressible/simpleFoam/turbineSiting
ENH: add generalised log-law type ground-normal inflow boundary conditions for
wind velocity and turbulence quantities for homogeneous, two-dimensional,
dry-air, equilibrium and neutral atmospheric boundary layer (ABL) modelling
ENH: remove `zGround` entry, which is now automatically computed
ENH: add `displacement height` entry, `d`
ENH: add generalised atmBoundaryLayerInletOmega boundary condition
ENH: add a verification case for atmBoundaryLayerInlet BCs
DOC: improve atmBoundaryLayerInlet header documentation
BUG: fix value-entry behaviour in atmBoundaryLayerInlet (fixes#1578)
Without this change:
- for serial-parallel computations, if `value` entry is available in
an `atmBoundaryLayerInlet` BC, the theoretical ABL profile expressions
are not computed, and the `value` entry content is used as a profile data
- for parallel computations, if `value` entry is not available, `decomposePar`
could not be executed.
With this change:
- assuming `value` entry is always be present, the use of `value` entry for
the ABL profile specification is determined by a flag `initABL`
- the default value of the optional flag `initABL` is `true`, but whenever
`initABL=true` is executed, `initABL` is overwritten as `false` for the
subsequent runs, so that `value` entry can be safely used.
Thanks Per Jørgensen for the bug report.
BUG: ensure atmBoundaryInlet conditions are Galilean-invariant (fixes#1692)
Related references:
The ground-normal profile expressions (tag:RH):
Richards, P. J., & Hoxey, R. P. (1993).
Appropriate boundary conditions for computational wind
engineering models using the k-ε turbulence model.
In Computational Wind Engineering 1 (pp. 145-153).
DOI:10.1016/B978-0-444-81688-7.50018-8
Modifications to preserve the profiles downstream (tag:HW):
Hargreaves, D. M., & Wright, N. G. (2007).
On the use of the k–ε model in commercial CFD software
to model the neutral atmospheric boundary layer.
Journal of wind engineering and
industrial aerodynamics, 95(5), 355-369.
DOI:10.1016/j.jweia.2006.08.002
Expression generalisations to allow height
variation for turbulence quantities (tag:YGCJ):
Yang, Y., Gu, M., Chen, S., & Jin, X. (2009).
New inflow boundary conditions for modelling the neutral equilibrium
atmospheric boundary layer in computational wind engineering.
J. of Wind Engineering and Industrial Aerodynamics, 97(2), 88-95.
DOI:10.1016/j.jweia.2008.12.001
The generalised ground-normal profile expression for omega (tag:YGJ):
Yang, Y., Gu, M., & Jin, X., (2009).
New inflow boundary conditions for modelling the
neutral equilibrium atmospheric boundary layer in SST k-ω model.
In: The Seventh Asia-Pacific Conference on Wind Engineering,
November 8-12, Taipei, Taiwan.
Reproduced benchmark:
Rectangular prism shown in FIG 1 of
Hargreaves, D. M., & Wright, N. G. (2007).
On the use of the k–ε model in commercial CFD software
to model the neutral atmospheric boundary layer.
Journal of wind engineering and
industrial aerodynamics, 95(5), 355-369.
DOI:10.1016/j.jweia.2006.08.002
Benchmark data:
HW, 2007 FIG 6
TUT: update simpleFoam/turbineSiting tutorial accordingly
- previously introduced `getOrDefault` as a dictionary _get_ method,
now complete the transition and use it everywhere instead of
`lookupOrDefault`. This avoids mixed usage of the two methods that
are identical in behaviour, makes for shorter names, and promotes
the distinction between "lookup" access (ie, return a token stream,
locate and return an entry) and "get" access (ie, the above with
conversion to concrete types such as scalar, label etc).
- Eg, with surface writers now in surfMesh, there are fewer libraries
depending on conversion and sampling.
COMP: regularize linkage ordering and avoid some implicit linkage (#1238)
- makes the intent clearer and avoids the need for additional
constructor casting. Eg,
labelList(10, Zero) vs. labelList(10, 0)
scalarField(10, Zero) vs. scalarField(10, scalar(0))
vectorField(10, Zero) vs. vectorField(10, vector::zero)
- use the dictionary 'get' methods instead of readScalar for
additional checking
Unchecked: readScalar(dict.lookup("key"));
Checked: dict.get<scalar>("key");
- In templated classes that also inherit from a dictionary, an additional
'template' keyword will be required. Eg,
this->coeffsDict().template get<scalar>("key");
For this common use case, the predefined getXXX shortcuts may be
useful. Eg,
this->coeffsDict().getScalar("key");
Previously the coordinate system functionality was split between
coordinateSystem and coordinateRotation. The coordinateRotation stored
the rotation tensor and handled all tensor transformations.
The functionality has now been revised and consolidated into the
coordinateSystem classes. The sole purpose of coordinateRotation
is now just to provide a selectable mechanism of how to define the
rotation tensor (eg, axis-angle, euler angles, local axes) for user
input, but after providing the appropriate rotation tensor it has
no further influence on the transformations.
--
The coordinateSystem class now contains an origin and a base rotation
tensor directly and various transformation methods.
- The origin represents the "shift" for a local coordinate system.
- The base rotation tensor represents the "tilt" or orientation
of the local coordinate system in general (eg, for mapping
positions), but may require position-dependent tensors when
transforming vectors and tensors.
For some coordinate systems (currently the cylindrical coordinate system),
the rotation tensor required for rotating a vector or tensor is
position-dependent.
The new coordinateSystem and its derivates (cartesian, cylindrical,
indirect) now provide a uniform() method to define if the rotation
tensor is position dependent/independent.
The coordinateSystem transform and invTransform methods are now
available in two-parameter forms for obtaining position-dependent
rotation tensors. Eg,
... = cs.transform(globalPt, someVector);
In some cases it can be useful to use query uniform() to avoid
storage of redundant values.
if (cs.uniform())
{
vector xx = cs.transform(someVector);
}
else
{
List<vector> xx = cs.transform(manyPoints, someVector);
}
Support transform/invTransform for common data types:
(scalar, vector, sphericalTensor, symmTensor, tensor).
====================
Breaking Changes
====================
- These changes to coordinate systems and rotations may represent
a breaking change for existing user coding.
- Relocating the rotation tensor into coordinateSystem itself means
that the coordinate system 'R()' method now returns the rotation
directly instead of the coordinateRotation. The method name 'R()'
was chosen for consistency with other low-level entities (eg,
quaternion).
The following changes will be needed in coding:
Old: tensor rot = cs.R().R();
New: tensor rot = cs.R();
Old: cs.R().transform(...);
New: cs.transform(...);
Accessing the runTime selectable coordinateRotation
has moved to the rotation() method:
Old: Info<< "Rotation input: " << cs.R() << nl;
New: Info<< "Rotation input: " << cs.rotation() << nl;
- Naming consistency changes may also cause code to break.
Old: transformVector()
New: transformPrincipal()
The old method name transformTensor() now simply becomes transform().
====================
New methods
====================
For operations requiring caching of the coordinate rotations, the
'R()' method can be used with multiple input points:
tensorField rots(cs.R(somePoints));
and later
Foam::transformList(rots, someVectors);
The rotation() method can also be used to change the rotation tensor
via a new coordinateRotation definition (issue #879).
The new methods transformPoint/invTransformPoint provide
transformations with an origin offset using Cartesian for both local
and global points. These can be used to determine the local position
based on the origin/rotation without interpreting it as a r-theta-z
value, for example.
================
Input format
================
- Streamline dictionary input requirements
* The default type is cartesian.
* The default rotation type is the commonly used axes rotation
specification (with e1/e2/3), which is assumed if the 'rotation'
sub-dictionary does not exist.
Example,
Compact specification:
coordinateSystem
{
origin (0 0 0);
e2 (0 1 0);
e3 (0.5 0 0.866025);
}
Full specification (also accepts the longer 'coordinateRotation'
sub-dictionary name):
coordinateSystem
{
type cartesian;
origin (0 0 0);
rotation
{
type axes;
e2 (0 1 0);
e3 (0.5 0 0.866025);
}
}
This simplifies the input for many cases.
- Additional rotation specification 'none' (an identity rotation):
coordinateSystem
{
origin (0 0 0);
rotation { type none; }
}
- Additional rotation specification 'axisAngle', which is similar
to the -rotate-angle option for transforming points (issue #660).
For some cases this can be more intuitive.
For example,
rotation
{
type axisAngle;
axis (0 1 0);
angle 30;
}
vs.
rotation
{
type axes;
e2 (0 1 0);
e3 (0.5 0 0.866025);
}
- shorter names (or older longer names) for the coordinate rotation
specification.
euler EulerRotation
starcd STARCDRotation
axes axesRotation
================
Coding Style
================
- use Foam::coordSystem namespace for categories of coordinate systems
(cartesian, cylindrical, indirect). This reduces potential name
clashes and makes a clearer declaration. Eg,
coordSystem::cartesian csys_;
The older names (eg, cartesianCS, etc) remain available via typedefs.
- added coordinateRotations namespace for better organization and
reduce potential name clashes.
Specialized variants of the power law porosity and k epsilon turbulence models
developed to simulate atmospheric flow over forested and non-forested complex
terrain.
Class
Foam::powerLawLopesdaCosta
Description
Variant of the power law porosity model with spatially varying
drag coefficient
given by:
\f[
S = -\rho C_d \Sigma |U|^{(C_1 - 1)} U
\f]
where
\vartable
\Sigma | Porosity surface area per unit volume
C_d | Model linear coefficient
C_1 | Model exponent coefficient
\endvartable
Reference:
\verbatim
Costa, J. C. P. L. D. (2007).
Atmospheric flow over forested and non-forested complex terrain.
\endverbatim
Class
Foam::RASModels::kEpsilonLopesdaCosta
Description
Variant of the standard k-epsilon turbulence model with additional source
terms to handle the changes in turbulence in porous regions represented by
the powerLawLopesdaCosta porosity model.
Reference:
\verbatim
Costa, J. C. P. L. D. (2007).
Atmospheric flow over forested and non-forested complex terrain.
\endverbatim
The default model coefficients are
\verbatim
kEpsilonLopesdaCostaCoeffs
{
Cmu 0.09;
C1 1.44;
C2 1.92;
sigmak 1.0;
sigmaEps 1.3;
}
\endverbatim
Tutorial case to follow.
