Author(s)

Christoph Bosshard¹, Michel O. Deville², Abdelouahab Dehbi¹, Emmanuel Leriche³

¹Paul Scherrer Institut, Laboratory for Thermal-Hydraulics (LTH), Villigen PSI, Switzerland.
²école Polytechnique Fédérale de Lausanne, School of Engineering, Lausanne, Switzerland.
³Université de Lille 1, Laboratoire de Mécanique, Boulevard Paul Langevin, Villeneuve d'Ascq Cedex, France.

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.

Spectral Element Method, Under-Resolved Direct Numerical Simulation, Large Eddy Simulation, Lid-Driven Cavity, Differentially Heated Cavity

Bosshard, C. , Deville, M. , Dehbi, A. and Leriche, E. (2015) UDNS or LES, That Is the Question. Open Journal of Fluid Dynamics, 5, 339-352. doi: 10.4236/ojfd.2015.54034.