Motion of grain on the Screen Surface under Elliptical Motion (II)

Abstract

Succeeding to the previous report, this paper dealt with the theoretical analysis and expermental studies concerning the flowing velocity of a grain on the oscillating screen in elliptical motion. The objective of this work was to check the validity of the theory. The point on the connecting rod (b) of the four-bar linkage was adapted to oscillate the screen in the elliptical motion. The measuring method for the experiment was the same as described in the first paper. The motion of a grain on the screen surface was analytically studied with the help of the pictures of the stroboscope and the oscillogram of acceleration and phase angles.
The main results were as follows.
1) In the case of counter-flow, the mean velocity of a grain increased with the increasing the frequency and decreased with the increasing of minor axis of ellipse. In the case of con-flow, when the frequency of screen exceeded the limits, the mean velocity of a grain gradually decreased.
2) In the case of counter-flow, the motion of a grain on the screen surface changed from positive sliding motion to jumping motion. In the case of con-flow, the motion of a grain on the screen surface changed from negative sliding motion to jumping motion.
3) Excepting the rolling motion of a grain, the mean velocity of a grain of theoretical analysis, was approximately in accordance with the experimental results.