Vaggelis Papoutsis authored 3 years ago and Andrew Heather committed 3 years ago

A Helmholtz-like filter is applied to the original field of sensitivity
derivatives. The corresponding PDE is solved on the sensitivity patches,
using the finite area infrastructure. A smoothing radius is needed,
which is computed based on the average 'length' of the boundary faces,
if not provided by the user explicitly.

If an faMesh is provided, it will be used; otherwise it will be created
on the fly based on either an faMeshDefinition dictionary in system or
one constructed internally based on the sensitivity patches.

A set of libraries and executables creating a workflow for performing
gradient-based optimisation loops. The main executable (adjointOptimisationFoam)
solves the flow (primal) equations, followed by the adjoint equations and,
eventually, the computation of sensitivity derivatives.

Current functionality supports the solution of the adjoint equations for
incompressible turbulent flows, including the adjoint to the Spalart-Allmaras
turbulence model and the adjoint to the nutUSpaldingWallFunction, [1], [2].

Sensitivity derivatives are computed with respect to the normal displacement of
boundary wall nodes/faces (the so-called sensitivity maps) following the
Enhanced Surface Integrals (E-SI) formulation, [3].

The software was developed by PCOpt/NTUA and FOSS GP, with contributions from

Dr. Evangelos Papoutsis-Kiachagias,
Konstantinos Gkaragounis,
Professor Kyriakos Giannakoglou,
Andy Heather

and contributions in earlier version from

Dr. Ioannis Kavvadias,
Dr. Alexandros Zymaris,
Dr. Dimitrios Papadimitriou

[1] A.S. Zymaris, D.I. Papadimitriou, K.C. Giannakoglou, and C. Othmer.
Continuous adjoint approach to the Spalart-Allmaras turbulence model for
incompressible flows. Computers & Fluids, 38(8):1528–1538, 2009.

[2] E.M. Papoutsis-Kiachagias and K.C. Giannakoglou. Continuous adjoint methods
for turbulent flows, applied to shape and topology optimization: Industrial
applications. 23(2):255–299, 2016.

[3] I.S. Kavvadias, E.M. Papoutsis-Kiachagias, and K.C. Giannakoglou. On the
proper treatment of grid sensitivities in continuous adjoint methods for shape
optimization. Journal of Computational Physics, 301:1–18, 2015.

Integration into the official OpenFOAM release by OpenCFD

- 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)

Henry Weller authored 7 years ago and Andrew Heather committed 7 years ago

Now pimpleDyMFoam is exactly equivalent to pimpleFoam when running on a
staticFvMesh.  Also when the constant/dynamicMeshDict is not present a
staticFvMesh is automatically constructed so that the pimpleDyMFoam solver can
run any pimpleFoam case without change.

pimpleDyMFoam: Store Uf as an autoPtr for better error handling

pimpleFoam: Set initial deltaT from the Courant number

for improved stability on start-up and compatibility with pimpleDyMFoam

ENH: pimpleFoam: Merged dynamic mesh functionality of pimpleDyMFoam into pimpleFoam

and replaced pimpleDyMFoam with a script which reports this change.

The pimpleDyMFoam tutorials have been moved into the pimpleFoam directory.

This change is the first of a set of developments to merge dynamic mesh
functionality into the standard solvers to improve consistency, usability,
flexibility and maintainability of these solvers.

Henry G. Weller
CFD Direct Ltd.

tutorials/incompressible/pimpleFoam: Updated pimpleDyMFoam tutorials to run pimpleFoam

Renamed tutorials/incompressible/pimpleFoam/RAS/wingMotion/wingMotion2D_pimpleDyMFoam

-> tutorials/incompressible/pimpleFoam/RAS/wingMotion/wingMotion2D_pimpleFoam

fvOptions are transferred to the database on construction using
fv::options::New which returns a reference.  The same function can be
use for construction and lookup so that fvOptions are now entirely
demand-driven.

The abstract base-classes for fvOptions now reside in the finiteVolume
library simplifying compilation and linkage.  The concrete
implementations of fvOptions are still in the single monolithic
fvOptions library but in the future this will be separated into smaller
libraries based on application area which may be linked at run-time in
the same manner as functionObjects.

The old separate incompressible and compressible libraries have been removed.

Most of the commonly used RANS and LES models have been upgraded to the
new framework but there are a few missing which will be added over the
next few days, in particular the realizable k-epsilon model.  Some of
the less common incompressible RANS models have been introduced into the
new library instantiated for incompressible flow only.  If they prove to
be generally useful they can be templated for compressible and
multiphase application.

The Spalart-Allmaras DDES and IDDES models have been thoroughly
debugged, removing serious errors concerning the use of S rather than
Omega.

The compressible instances of the models have been augmented by a simple
backward-compatible eddyDiffusivity model for thermal transport based on
alphat and alphaEff.  This will be replaced with a separate run-time
selectable thermal transport model framework in a few weeks.

For simplicity and ease of maintenance and further development the
turbulent transport and wall modeling is based on nut/nuEff rather than
mut/muEff for compressible models so that all forms of turbulence models
can use the same wall-functions and other BCs.

All turbulence model selection made in the constant/turbulenceProperties
dictionary with RAS and LES as sub-dictionaries rather than in separate
files which added huge complexity for multiphase.

All tutorials have been updated so study the changes and update your own
cases by comparison with similar cases provided.

Sorry for the inconvenience in the break in backward-compatibility but
this update to the turbulence modeling is an essential step in the
future of OpenFOAM to allow more models to be added and maintained for a
wider range of cases and physics.  Over the next weeks and months more
turbulence models will be added of single and multiphase flow, more
additional sub-models and further development and testing of existing
models.  I hope this brings benefits to all OpenFOAM users.

Henry G. Weller

NamedEnum (bug in compiler?)
molecule (Graham dealing with it)
lex (no comment)
VTK (again no comment)