Synthesis of homogeneous anisotropic divergence-free turbulent fields with prescribed second-order statistics by vortex dipoles
Synthesis of homogeneous anisotropic divergence-free turbulent fields with prescribed second-order statistics by vortex dipoles
复制标题
通过涡旋偶极子合成具有指定二阶统计量的均匀各向异性无发散湍流场
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
E. Hassel
中科院分区：
文献类型：
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作者：
N. Kornev;E. Hassel
本通讯给出了用规定的壳和能谱生成湍流速度场的数学程序。速度场表示为由一组随机分布的涡旋偶极子（涡子）引起的速度之和。从合成场的壳和能谱等于规定能谱的条件下，得到了涡的内部结构的闭型解析解。将该方法应用于具有衰减湍流谱和均匀湍流典型速度能谱的湍流场。衰变湍流的解是衰变最后阶段湍流场的Navier-Stokes方程的精确解析解。
This Communication presents a mathematical procedure for generation of turbulent velocity fields with prescribed shell-summed energy spectra. The velocity field is represented as the sum of velocities induced by a set of randomly distributed vortex dipoles (vortons). Closed-form analytical solutions are found for the inner structure of the vortons from the condition that the shell-summed energy spectrum of the synthesizing field is equal to the prescribed one. The proposed procedure is applied to turbulent fields with the spectrum of the decaying turbulence and the typical velocity energy spectrum of homogeneous turbulence. The solution for decaying turbulence is the exact analytical solution of the Navier-Stokes equation for the turbulent field in the final stage of the decay.