ABSTRAKT

Results of direct numerical simulations (DNS) of vibrating grid turbulence are presented. Turbulence is generated at a grid in the x₁ − x₂ plane which vibrates normally to itself. There is no mean velocity in the flow. Hence, in a statistical sense turbulence is generated in a plane and diffuses out while at the same time gets damped due to dissipation. Due to zero mean shear there is no production of turbulence apart from the region at grid. Numerical simulations for two different Reynolds numbers (based on an amplitude and frequency of the grid) Re = 500, 1000 were performed using a spectral code. Statistics of turbulence was accumulated and the evolution of the turbulent/non-turbulent interface was detected and compared to the theoretical result obtained by Oberlack and Guenther (2003) using Lie group analysis. Good agreement was found between DNS and theoretical results.