【摘要】 对纤维悬浮剪切湍流中纤维旋转扩散系数进行了理论研究.首先建立了流场不同脉动速度梯度间的相关矩函数,然后推导出了纤维旋转扩散系数的表达式,该表达式依赖于特征长度、时间、速度和一个与壁面作用相关的无量纲参数.得到的纤维旋转扩散系数可以应用于非均匀和非各向同性的湍流场,此外还可以推广到三维湍流场,因而为纤维悬浮湍流场的研究提供了理论基础.更多还原

【Abstract】 The rotational dispersion coefficient of the fiber in the turbulent shear flow of fiber suspension was studied theoretically. The function of correlation moment between the different fluctuating velocity gradient of the flow was built. Then the expression of rotational dispersion coefficient is derived.Which is dependent on the characteristic length, time, velocity and a dimensionless parameter related to the effect of wall.The derived expression of rotational dispersion coefficient can be employed to the inhomogeneous and non-isotropic turbulent flows. Furthermore it can be expanded to three-dimensional turbulent flows and serves as the theoretical basis for solving the turbulent flow of fiber suspension.更多还原