Watanabe Takeshi, Iwayama Takahiro
Department of Engineering Physics, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan.
Phys Rev E Stat Nonlin Soft Matter Phys. 2007 Oct;76(4 Pt 2):046303. doi: 10.1103/PhysRevE.76.046303. Epub 2007 Oct 3.
The local and nonlocal characteristics of triad enstrophy transfer in the enstrophy inertial range of generalized two-dimensional turbulence, so-called alpha turbulence, are investigated using direct numerical simulations, with a special emphasis on alpha=1 , 2, and 3. The enstrophy transfer via nonlocal triad interactions dominates the transfer dynamics in the enstrophy inertial range, irrespective of alpha . However, the contributions from more local interactions to the total enstrophy transfer increase as alpha decreases. The results are discussed in connection with the local and nonlocal transition of the enstrophy transfer at alpha=2 expected from the phenomenological scaling theory. The specific nature of the enstrophy transfer in surface quasigeostrophic turbulence (alpha=1) is also discussed.
利用直接数值模拟研究了广义二维湍流（即所谓的α湍流）在涡量惯性范围内三元组涡量传递的局部和非局部特征，特别关注α = 1、2和3的情况。无论α为何值，通过非局部三元组相互作用的涡量传递在涡量惯性范围内主导着传递动力学。然而，随着α减小，更多局部相互作用对总涡量传递的贡献增加。结合现象学标度理论预期的α = 2时涡量传递的局部和非局部转变来讨论这些结果。还讨论了表面准地转湍流（α = 1）中涡量传递的具体性质。
