Berti S, Bistagnino A, Boffetta G, Celani A, Musacchio S
Department of Mathematics and Statistics, University of Helsinki, P.O. Box 68, FIN-00014 Helsinki, Finland.
Phys Rev E Stat Nonlin Soft Matter Phys. 2008 May;77(5 Pt 2):055306. doi: 10.1103/PhysRevE.77.055306. Epub 2008 May 29.
We report numerical evidence of elastic turbulence phenomenology in a two-dimensional periodic Kolmogorov flow. By direct numerical simulations of the Oldroyd-B viscoelastic model at very small Reynolds numbers, we find that above the elastic instability threshold the flow develops an elastic turbulent regime. We observe that both the turbulent drag and the Lyapunov exponent increase with the Weissenberg number, indicating the presence of a disordered, turbulentlike mixing flow. The energy spectrum develops a power-law scaling range with an exponent close to the experimental and theoretical expectations.
我们报告了二维周期性柯尔莫哥洛夫流中弹性湍流现象学的数值证据。通过在非常小的雷诺数下对奥尔德罗伊德 - B 粘弹性模型进行直接数值模拟,我们发现,在弹性不稳定性阈值以上,流动发展出一种弹性湍流状态。我们观察到,湍流阻力和李雅普诺夫指数均随魏森贝格数增加,这表明存在一种无序的、类似湍流的混合流。能谱发展出一个幂律标度范围,其指数接近实验和理论预期。