ITHACA-SEM

Synopsis

ITHACA-SEM: In real Time Highly Advanced Computational Applications with Spectral Element Methods - Reduced Order Models for Nektar++ , is a C++ package for the Model Order Reduction that uses simulations from the spectral/hp element software Nektar++. It uses Eigen to perform the matrix decompositions required for parametric model order reduction. The GitHub repository is available here: ITHACA-SEM.

Requirements

No particular requirements. Standard cmake/make install carries over from Nektar++.

Features

As of Aug. 2021:

• merged with the current Nektar++ master branch
• steady-state Navier-Stokes solutions (intrusive)
• unsteady Navier-Stokes solutions (non-intrusive)
• allows using a variable Reynolds number (specified by the kinematic viscosity) as parameter and geometry
• perform offline simulation in ITHACA-SEM or use precomputed Nektar++ *.fld files as snapshot solutions
• computes a POD ROM
• computes ROM parameter sweeps

References

ITHACA-SEM has been used in the following publications, i.e., either the c++ version or a previous python3 version, which is now listed under 'deprecated' in the GitHub repo.

• M. Hess, G. Rozza. "A Spectral Element Reduced Basis Method in Parametric CFD". In: Radu F., Kumar K., Berre I., Nordbotten J., Pop I. (eds) Numerical Mathematics and Advanced Applications ENUMATH 2017. Lecture Notes in Computational Science and Engineering, vol 126. Springer, Cham (2019). "ArXiv preprint"

• M. Hess, A. Quaini, G. Rozza. "Reduced Basis Model Order Reduction for Navier-Stokes equations in domains with walls of varying curvature", International Journal of Computational Fluid Dynamics, 34(2):119-126, 2020. "ArXiv preprint"

• M. Hess, A. Alla, A. Quaini, G. Rozza, M. Gunzburger. "A Localized Reduced-Order Modeling Approach for PDEs with Bifurcating Solutions", Comput. Methods Appl. Mech. Engrg., 351:379-403, 2019. "ArXiv preprint"

• M. Hess, A. Quaini, G. Rozza. "A Spectral Element Reduced Basis Method for Navier-Stokes Equations with Geometric Variations". In: Sherwin, S. J., Moxey, D., Peiro, J., Vincent, P. E., Schwab, C. (eds) Spectral and High Order Methods for Partial Differential Equations ICOSAHOM 2018. Lecture Notes in Computational Science and Engineering book series (LNCSE, volume 134), Springer International Publishing, Cham, 561-571, 2020. "ArXiv preprint"

• M. Pintore, F. Pichi, M. Hess, G. Rozza, C. Canuto. "Efficient Computation of Bifurcation Diagrams with a Deflated Approach to Reduced Basis Spectral Element Method", 2019, submitted.

Links

GitHub repository: https://github.com/mathLab/ITHACA-SEM

Website: https://mathlab.sissa.it/ITHACA-SEM

Contact

Martin Hess