Biferale L, Khomenko D, L'vov V, Pomyalov A, Procaccia I, Sahoo G
Department of Physics and INFN, University of Rome, Tor Vergata, 00133 Roma, Italy.
Laboratoire de physique l'Ecole normale supérieure, CNRS, 75005 Paris, France.
Phys Rev Lett. 2019 Apr 12;122(14):144501. doi: 10.1103/PhysRevLett.122.144501.
Three-dimensional anisotropic turbulence in classical fluids tends towards isotropy and homogeneity with decreasing scales, allowing-eventually-the abstract model of homogeneous and isotropic turbulence to be relevant. We show here that the opposite is true for superfluid ^{4}He turbulence in three-dimensional counterflow channel geometry. This flow becomes less isotropic upon decreasing scales, becoming eventually quasi-two-dimensional. The physical reason for this unusual phenomenon is elucidated and supported by theory and simulations.
经典流体中的三维各向异性湍流随着尺度减小趋向于各向同性和均匀性，最终使得均匀和各向同性湍流的抽象模型变得适用。我们在此表明，对于三维逆流通道几何结构中的超流⁴He湍流，情况则相反。随着尺度减小，这种流动的各向同性降低，最终变为准二维。这一异常现象的物理原因通过理论和模拟得到了阐明和支持。
