On the eddy system in the wake of flat circular plates in three dimensional flow

Abstract

The method of colour bands for revealing the characteristics of the motion of water was first used by Osborne Reynolds some 50 years ago in the determination of the critical velocity at which the streamline motion in parallel pipes broke down. Since that time several attempts have been made to uses the same method for the study of vortex motion, but owing apparently to lack of sufficient precautions to ensure that all internal motions in the reservoir supplying the stream had disappeared before the experiments were made, the success achieved has not been as great as might have been expected. In 1910 a small water channel consisting of a rectangular canal 3 inches wide and 4 inches deep by 10 feet in length was constructed at the National Physical Laboratory for the study of the flow round plates and models and the results of a series of experiments made in the channel were described by Mr. C. G. Eden in his paper communicated to the Advisory Committee for Aeronautics. The Flow in this channel, however, was not altogether satisfactory for although the initial disturbances in the water supply were reduced by means of baffle plates and the use of a large supply tank, so that no eddies were present, there wee indications that the direction of motion at nay point was not independent of the time. The information obtained by Mr. Eden with this channel was of considerable value in revealing the nature of the flow in the wake of inclined plates and streamlined models.