The investigation of non-buoyant smoke rings

General characteristics of the isolated masses of a nonbuoyant fluid puff released in a fluid of identical density have been investigated. However, this is not the case with the horizontal motion of a compressible fluid. This study is so conducted as to probe the phenomena of motion of the smoke ring which moves through and associates with its confined and unstratified surroundings. The Eulerian velocities of the ring along the ring axis, the momentum, and the numerical constants related to the ring motion are studied in this dissertation both analytically and experimentally. The results are presented as functions of elapsed time or distance corresponding to the time. Two distinguished regions of ring motion have been found experimentally by the sudden change of characteristic dimension of the ring as it travels downstream. It is observed that the Eulerian velocities, momentum, and force acting on the ring in each region are distinguishably different. They may be approximately predicted by the theories of ideal fluids in the first (or initial) region, and by theories of turbulent flow in the second (or "turbulent") region.