TITLE:
UDNS or LES, That Is the Question
AUTHORS:
Christoph Bosshard, Michel O. Deville, Abdelouahab Dehbi, Emmanuel Leriche
KEYWORDS:
Spectral Element Method, Under-Resolved Direct Numerical Simulation, Large Eddy Simulation, Lid-Driven Cavity, Differentially Heated Cavity
JOURNAL NAME:
Open Journal of Fluid Dynamics,
Vol.5 No.4,
December
18,
2015
ABSTRACT: In the framework of the spectral element method, a comparison is carried out on turbulent first-and second-order statistics generated by large eddy simulation (LES), under-resolved (UDNS) and fully resolved direct numerical simulation (DNS). The LES is based on classical models like the dynamic Smagorinsky approach or the approximate deconvolution method. Two test problems are solved: the lid-driven cubical cavity and the differentially heated cavity. With the DNS data as benchmark solutions, it is shown that the numerical results produced by the UDNS calculation are of the same accuracy, even in some cases of better quality, as the LES computations. The conclusion advocates the use of UDNS and calls for improvement of the available algorithms.