4 papers
Geometric derivation and structure-preserving simulation of quasi-geostrophy on the sphere
Erwin Luesink, Arnout Franken, Sagy Ephrati +1
We present a geometric derivation of the quasi-geostrophic equations on the sphere, starting from the rotating shallow water equations. We utilise perturbation series methods in vo…
Critical latitude in global quasi-geostrophic flow on a rotating sphere
Arnout Franken, Erwin Luesink, Sagy Ephrati +1
In this paper, we study geostrophic turbulence without external forcing or dissipation, using a Casimir-preserving numerical method. The research examines the formation of large zo…
Casimir preserving numerical method for global multilayer geostrophic turbulence
Arnout Franken, Erwin Luesink, Sagy Ephrati +1
Accurate long-term predictions of large-scale flow features on planets are crucial for understanding global atmospheric and oceanic systems, necessitating the development of numeri…
A continuous data assimilation closure for modeling statistically steady turbulence in large-eddy simulation
Sagy Ephrati, Arnout Franken, Erwin Luesink +2
A closure model is presented for large-eddy simulation (LES) based on the three-dimensional variational data assimilation algorithm. The approach aims at reconstructing high-fideli…