On the Flow between Eccentric Rotating Cylinders when the Outer Cylinder Rotates

Abstract

In this paper the inertia effect of the flow between eccentric rotating cylinders, when outer cylinder rotates, is studied numerically covering the wide range of the parameters, such as eccentricity ratio, clearance ratio and so on. At the same time the whole pressure and shearing distribution and the force acting on the inner cylinder are calculated. The results obtained are as follows. (1) When Reynolds number is constant, the effect of inertia increases as the eccentricity ratio decreases in the range of 0.1∼0.9 and as the clearance ratio increases. (2) When the inertia effect is neglected, the form of pressure distribution in the region of negative pressure is the same as in the region of positive pressure. When the inertia effect, however, is taken into account, the max. value of negative pressure is larger than the max. value of positive pressure. The greater the effect of inertia, the greater the max. value of negative pressure. (3) Considering the effect of inertia, the inner cylinder is acted upon not only by the force perpendicular to the eccentric direction but also in the eccentric direction. (4) Torque acting on the inner cylinder is not influenced by inertia, although the distribution of shearing stress varies depending on whether the inertia force is taken into account or not.