Assessment of mesh adaptation algorithms for LES and DES simulation of
detached flows

B. Sauvage*,†, F. Miralles¶, S. Wornom¶, B. Koobus¶, F. Alauzet◦ and A. Dervieux †,‡

† Université Côte d'Azur, INRIA, Sophia-Antipolis, France, bastien.sauvage@inria.fr

¶ IMAG, Univ. Montpellier, CNRS, France, florian.miralles@umontpellier.fr,
bruno.koobus@umontpellier.fr, stephen.wornom@inria.fr

◦ INRIA Saclay Ile-de-France, Palaiseau, France, frederic.alauzet@inria.fr

‡ Lemma, Biot, France, alain.dervieux@inria.fr

ABSTRACT

The proposed communication, discusses the adaptation of a transient fixed point adaptation algorithm to
the computation of detached flows with LES of VMS type [3, 4] and DDES (Delayed Detached Eddy
Simulation) models.

The Transient Fixed Point adaptation algorithm relies on a representation of the mesh by a Riemannian
metric [1]. We seek for an optimal metric according to a criterion prescribed by the user. In the Transient
Fixed Point, the metric, and then the mesh, is frozen for the timesteps of a subinterval of the time interval.
Several strategies are possible in the choice of the subinterval size, from a rather small interval allowing
to follow many details to an interval of one or several main periods, and will be discussed during the
presentation. Iterative remeshings are applied in order to reach some fixed point, see [2]. Refinement
criteria involve Mach number fields for resolution boundary layers and pressure time derivatives in order
to better capture acoustics.

Flows around cylinder with Reynolds number from 3900 to 1 million, airfoils with mean and high angle of attack and a Caradonna rotor will be considered for the evaluation, with comparison with experiments and calculations with taylored fixed meshes.

REFERENCES

[1] Dervieux, A., Alauzet, F., Loseille, A., Koobus, B. (2022). Mesh Adaptation for Computational Fluid Dynamics 1 and 2. ISTE Ltd, London, and John Wiley and Sons, New York.

[2] F. Alauzet, P.J. Frey, P.-L. George, and B. Mohammadi. 3D transient fixed point mesh adaptation for time-dependent problems: Application to CFD simulations. J. Comp. Phys., 222:592–623, 2007.

[3] C. Moussaed, M.V. Salvetti, S. Wornom, B. Koobus and A. Dervieux, Simulation of the flow past a circular cylinder in the supercritical regime by blending RANS and variational-multiscale LES models, Journal of Fluids and Structures, Volume 47, 2014, pages 114-123.

[4] E. Itam, S. Wornom, B. Koobus, and A. Dervieux, Combining a DDES model with a dynamic variational multiscale formulation, 12th International ERCOFTAC Symposium on Engineering Turbulence Modelling and Measurements (ETMM12), 2018.