Description
An incompressible Casson non-Newtonian viscosity model.
References:
\verbatim
Casson, N. (1959).
Rheology of disperse systems.
In Proceedings of a Conference Organized by the
British Society of Rheology.
Pergamon Press, New York.
Fournier, R. L. (2011).
Basic transport phenomena in biomedical engineering.
CRC Press.
\endverbatim
Contributed by Sergey Sindeev
Description
Allows specification of different writing frequency of objects registered
to the database.
It has similar functionality as the main time database through the
\c writeControl setting:
- timeStep
- writeTime
- adjustableRunTime
- runTime
- clockTime
- cpuTime
It also has the ability to write the selected objects that were defined
with the respective write mode for the requested \c writeOption, namely:
- \c autoWrite - objects set to write at output time
- \c noWrite - objects set to not write by default
- \c anyWrite - any option of the previous two
Example of function object specification:
\verbatim
writeObjects1
{
type writeObjects;
libs ("libutilityFunctionObjects.so");
...
objects (obj1 obj2);
writeOption anyWrite;
}
\endverbatim
Patch contributed by Bruno Santos
Resolves bug-report http://bugs.openfoam.org/view.php?id=2090
Time: call functionObject 'execute()' and 'end()' for last time-step
Now the operation of functionObject 'end()' call is consistent between running and post-processing
Now the number of iterations to solve each component in a segregated
solution are stored and returned in the SolverPerformance class.
Resolves bug-report http://bugs.openfoam.org/view.php?id=2189
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.
