Effects of Inhomogeneity and of Shear Flow in Weak Turbulent Fields
Effects of Inhomogeneity and of Shear Flow in Weak Turbulent Fields
复制标题
弱湍流场中不均匀性和剪切流的影响
DOI：
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发表时间：
1961
期刊：
影响因子：
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通讯作者：
R. G. Deissler
中科院分区：
文献类型：
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作者：
R. G. Deissler
弱湍流的谱可用于： (1) 在均匀平均速度方向上不均匀的湍流； (2) 由于边界的存在，最初均匀的湍流在横向上变得不均匀； (3) 具有均匀平均横向速度梯度的均匀湍流。该处理基于两点相关性和谱方程。不均匀性的影响是导致湍流向湍流强度降低的方向扩散。纵向不均匀性主要在能谱的高波数部分产生能量积累，而横向不均匀性会导致流体中某一点的能量耗尽，并且不会改变能谱的形状。对于具有均匀横向速度梯度的均匀湍流，能量通过谱方程中的湍流产生项从平均流转移到湍流中。在高速梯度下，生产范围...
Spectra for weak turbulence are found for: (1) turbulence inhomogeneous in the direction of a uniform mean velocity; (2) an initially homogeneous turbulence becoming inhomogeneous in a transverse direction because of the presence of boundaries; and (3) turbulence homogeneous with a uniform mean transverse velocity gradient. The treatment is based on two‐point correlation and spectral equations. The effect of inhomogeneity is to cause a diffusion of turbulence in the direction of decreasing turbulent intensity. Longitudinal inhomogeneity produces an accumulation of energy mainly in the high wave‐number portions of the energy spectrum, whereas the transverse inhomogeneity causes a depletion of energy at a point in the fluid and does not alter the shape of the spectrum. For homogeneous turbulence with a uniform transverse velocity gradient, energy is transferred from the mean flow into the turbulence by a turbulent production term in the spectral equation. At high velocity gradients the production spectrum s...