An anisotropic synthetic turbulence method for Large-Eddy Simulation

Abstract

The method for generating anisotropic synthetic turbulence by Auerswald and Bange (2015) is extended to account for the integral length scales in y - and z -direction. This extension leads to more realistic tur- bulent structures. The method reproduces the given turbulence statistics very well and allows to set a number of turbulence parameters independently. In four Large-Eddy Simulations of a channel flow the synthetic turbulence is used as inflow boundary condition. The performance of the synthetic turbulence is tested and compared to the Direct Numerical Simulation (DNS) results by Moser et al. (1999). In these simulations the synthetic turbulence shows good performance in recovering realistic turbulence down- stream in the channel. The skin-friction coefficient converges to the level of the DNS. The profiles of the Reynolds stresses are very similar in the LES and the DNS except for the profiles of R + ww where large deviations occur.