纤维在流体中各种运动形态可能性的判别

研究纤维在气流中的运动,对新型纺纱有着重要的意义。本文用多球链作为单纤维的模型,讨论纤维在不可压缩牛顿粘性流体的任意流场中的任意运动,得到了多球链纤维在流体中各种运动形态受拉、压的判别式,所得结论与日常经验相符。

THE JUDGMENT OF THE POSSIBLE MOVING FORMS OF FIBERS SUSPENDED IN FLUID

To investigate the motion of fibers suspended in the air flow is of significance to the new spinning systems. The arbitrary motion of a single fiber suspended in an arbitrary flow field of an incompressible Neutonian viscous fluid is discussed with a multi-sphere chain consisting of n spheres and n minus one links simulating the fiber. The chain spheres experience such forces as gravity, buoyancy and stokes' drag of the fluid. The basic equations for the multi-sphere chain fiber suspended in fluid are established and the results obtained are summarized as follows. 1. The segment of a multi-sphere chain fiber suspended in fluid is tensioned if the relative velocity of the fluid coincided with its two spheric centers in the direction of their connecting rod does not have the trend which makes these two spheres approach each other. 2. If a segment of the multi-sphere chain fiber suspended in fluid is compressed, then the relative velocity of the fluid coincided with its two spheric centers in the direction of their connecting rod has the trend which makes these two spheres approach each other. 3. The ability of turbulent flow to change the form of a fiber in a pipe is found to be inferior to that of laminar flow. These conclusions conform with the actual practice.