Now the functionality to write single graph files or log files (vs time)
may be used in the creation of any form of functionObject, not just
those relating to a mesh region.
The diameter of the drops formed are obtained from the local capillary
length multiplied by the \c dCoeff coefficient which defaults to 3.3.
Reference:
Lefebvre, A. (1988).
Atomization and sprays
(Vol. 1040, No. 2756). CRC press.
Changed default mode of operation to use standard y+ based switching
rather than the previous ad hoc blending and added consistent handling
of the near-wall generation term.
This boundary condition provides a wall constraint on turbulnce specific
dissipation, omega for both low and high Reynolds number turbulence models.
The near-wall omega may be either blended between the viscous region and
logarithmic region values using:
\f[
\omega = sqrt(\omega_{vis}^2 + \omega_{log}^2)
\f]
where
\vartable
\omega_{vis} | omega in viscous region
\omega_{log} | omega in logarithmic region
\endvartable
see eq.(15) of:
\verbatim
Menter, F., Esch, T.
"Elements of Industrial Heat Transfer Prediction"
16th Brazilian Congress of Mechanical Engineering (COBEM),
Nov. 2001
\endverbatim
or switched between these values based on the laminar-to-turbulent y+ value
derived from kappa and E. Recent tests have shown that the standard
switching method provides more accurate results for 10 < y+ < 30 when used
with high Reynolds number wall-functions and both methods provide accurate
results when used with continuous wall-functions. Based on this the
standard switching method is used by default.
This boundary condition provides a turbulence dissipation wall constraint
for low- and high-Reynolds number turbulence models.
The condition can be applied to wall boundaries for which it
- calculates \c epsilon and \c G
- specifies the near-wall epsilon value
where
\vartable
epsilon | turblence dissipation field
G | turblence generation field
\endvartable
The model switches between laminar and turbulent functions based on the
laminar-to-turbulent y+ value derived from kappa and E.
Recent tests have shown that this formulation is more accurate than
the standard high-Reynolds number form for 10 < y+ < 30 with both
standard and continuous wall-functions.
Replaces epsilonLowReWallFunction and should be used for all
low-Reynolds number models for which the epsilonLowReWallFunction BC was
recommended.
of film flow on an inclined plane by Brun et.al.
Brun, P. T., Damiano, A., Rieu, P., Balestra, G., & Gallaire, F. (2015).
Rayleigh-Taylor instability under an inclined plane.
Physics of Fluids (1994-present), 27(8), 084107.
Until C++ supports 'concepts' the only way to support construction from
two iterators is to provide a constructor of the form:
template<class InputIterator>
List(InputIterator first, InputIterator last);
which for some types conflicts with
//- Construct with given size and value for all elements
List(const label, const T&);
e.g. to construct a list of 5 scalars initialized to 0:
List<scalar> sl(5, 0);
causes a conflict because the initialization type is 'int' rather than
'scalar'. This conflict may be resolved by specifying the type of the
initialization value:
List<scalar> sl(5, scalar(0));
The new initializer list contructor provides a convenient and efficient alternative
to using 'IStringStream' to provide an initial list of values:
List<vector> list4(IStringStream("((0 1 2) (3 4 5) (6 7 8))")());
or
List<vector> list4
{
vector(0, 1, 2),
vector(3, 4, 5),
vector(6, 7, 8)
};
Description
Langtry-Menter 4-equation transitional SST model
based on the k-omega-SST RAS model.
References:
Langtry, R. B., & Menter, F. R. (2009).
Correlation-based transition modeling for unstructured parallelized
computational fluid dynamics codes.
AIAA journal, 47(12), 2894-2906.
Menter, F. R., Langtry, R., & Volker, S. (2006).
Transition modelling for general purpose CFD codes.
Flow, turbulence and combustion, 77(1-4), 277-303.
Langtry, R. B. (2006).
A correlation-based transition model using local variables for
unstructured parallelized CFD codes.
Phd. Thesis, Universität Stuttgart.
Implemented by Henry G. Weller, CFD Direct in collaboration with Florian
Schwertfirm, Kreuzinger und Manhart Turbulenz GmbH.
rather than being calculated on construction and stored as member data.
The convergence warning has be replaced with the 'convergence()' member
function which returns 'true' if the SVD iteration converged, otherwise 'false'.
Provides efficient integration of complex laminar reaction chemistry,
combining the advantages of automatic dynamic specie and reaction
reduction with ISAT (in situ adaptive tabulation). The advantages grow
as the complexity of the chemistry increases.
References:
Contino, F., Jeanmart, H., Lucchini, T., & D’Errico, G. (2011).
Coupling of in situ adaptive tabulation and dynamic adaptive chemistry:
An effective method for solving combustion in engine simulations.
Proceedings of the Combustion Institute, 33(2), 3057-3064.
Contino, F., Lucchini, T., D'Errico, G., Duynslaegher, C.,
Dias, V., & Jeanmart, H. (2012).
Simulations of advanced combustion modes using detailed chemistry
combined with tabulation and mechanism reduction techniques.
SAE International Journal of Engines,
5(2012-01-0145), 185-196.
Contino, F., Foucher, F., Dagaut, P., Lucchini, T., D’Errico, G., &
Mounaïm-Rousselle, C. (2013).
Experimental and numerical analysis of nitric oxide effect on the
ignition of iso-octane in a single cylinder HCCI engine.
Combustion and Flame, 160(8), 1476-1483.
Contino, F., Masurier, J. B., Foucher, F., Lucchini, T., D’Errico, G., &
Dagaut, P. (2014).
CFD simulations using the TDAC method to model iso-octane combustion
for a large range of ozone seeding and temperature conditions
in a single cylinder HCCI engine.
Fuel, 137, 179-184.
Two tutorial cases are currently provided:
+ tutorials/combustion/chemFoam/ic8h18_TDAC
+ tutorials/combustion/reactingFoam/laminar/counterFlowFlame2D_GRI_TDAC
the first of which clearly demonstrates the advantage of dynamic
adaptive chemistry providing ~10x speedup,
the second demonstrates ISAT on the modest complex GRI mechanisms for
methane combustion, providing a speedup of ~4x.
More tutorials demonstrating TDAC on more complex mechanisms and cases
will be provided soon in addition to documentation for the operation and
settings of TDAC. Also further updates to the TDAC code to improve
consistency and integration with the rest of OpenFOAM and further
optimize operation can be expected.
Original code providing all algorithms for chemistry reduction and
tabulation contributed by Francesco Contino, Tommaso Lucchini, Gianluca
D’Errico, Hervé Jeanmart, Nicolas Bourgeois and Stéphane Backaert.
Implementation updated, optimized and integrated into OpenFOAM-dev by
Henry G. Weller, CFD Direct Ltd with the help of Francesco Contino.
Note: this reuses the existing storage rather than costly reallocation
which requires the initial allocation to be sufficient for the largest
size the ODE system might have. Attempt to set a size larger than the
initial size is a fatal error.
