Fluid nozzle system using self-propelling toroidal vortices for long-range jet impact

Abstract

A fluid nozzle system (nicknamed the 'RAP nozzle system') is disclosed that combines a pulse flow device with a toroidal vortex generator to create a high momentum, self propelling jet for increasing long-range jet impact forces. In a preferred embodiment, the RAP nozzle system comprises a fluid switch, without any moving mechanical part, which takes continuous flow normally exited through a nozzle and breaks it into discrete patterns of pulsed flow. The unsteady characteristics of the pulsed flow are then used with either single-stage ejectors, multi-stage ejectors or other devices to increase the momentum and/or the lateral size of the individual pulses. These fluid pulses are then used to generate a jet with large scale, stable toroidal vortices which travel long distances, downstream of the ejector(s), and apply large forces at impact. Unlike the prior art, such toroidal vortices are stable, carry large flow momentum, and propel themselves through the air (or other fluid) at a speed approximately ¼ the pulsed velocity of the fluid used to generate the vortices. Furthermore, the toroidal vortices travel beyond the RAP nozzle system with minimal mixing and minimal losses. Tests conducted have demonstrated that these toroidal vortices travel up to 10 times the distance of current continuous flow jets and can deliver an order of magnitude larger force to move particles at large distances from the nozzle exit when compared to the same energy, continuous jet. The same toroidal vortices generate stirring mechanisms at impact which can be useful in many applications. The RAP nozzle system can significantly improve the performance of leaf blowers, shop air nozzles, and all other products that utilize jet impact forces for particle movement. The same RAP nozzle system concept can be used in a significant number of other applications where fluid pulsations could be beneficial. Fluid pulsations increase the force of a fluid jet by adding impulsive forces similar to a jack hammer. These unsteady forces can be quite large and are directly related to the velocity of the jet at impact. In an alternate embodiment, the RAP nozzle concept can also carry a secondary fluid over a large distance without mixing the secondary fluid with the ambient fluid. The secondary fluid is carried in the core of the toroidal vortices generated.