New adjoint optimisation and tools

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

Integration into the official OpenFOAM release by OpenCFD