| 摘要 |
FIELD: physics.SUBSTANCE: invention relates to hydrodynamics and a method of exciting acoustic vibrations in a fluid medium and an apparatus for realising the method. The method involves forming a stream of the fluid medium and feeding said stream into a treatment zone having reflectors and flexible obstacles in form of mechanical resonators, generating parametric resonance vibrations at each point of the fluid medium, simultaneously increasing the amplitude of vibrations of each flexible obstacle in resonance conditions with parametric resonance vibrations, exciting harmonic acoustic vibrations in the fluid medium with formation of a cavitation zone and removing the treated fluid medium from the treatment zone. Vibrations are excited by moving the fluid medium relative the flexible obstacles which are fitted with cavitators which are mounted on mechanical resonators or are made in form of ends of resonators which cambered towards the incident flow, wherein the fluid medium flows around the obstacles in developed cavitation flow conditions with formation of a pulsating cavitation zone (cavern) whose surface serves as a source of acoustic vibrations, and resonance conditions of a defined overtone are created by placing flexible obstacles relative reflectors and each other at a distance which depends on acoustic properties of the fluid medium. The apparatus according to one of the versions has a housing made from at least two flat or curved plates which act as reflectors; mechanical resonators are made with ends which are cambered towards the incident flow or are fitted with cavitators, wherein the distance from the reflection points lying on the reflectors to mechanical resonators and the distance between the mechanical resonators is a multiple of ?/4, where ? is the wavelength of the fluid medium which corresponds to the frequency of acoustic vibrations in a defined medium.EFFECT: invention increases efficiency of exciting and generating vibrations of a fluid medium, widens the cavitation zone and also enables to obtain abrasive media which are stable over time, such media including dispersions, suspensions and emulsions, suitable for prolonged storage without deterioration of properties obtained from treatment owing to use of a fluid medium as an acoustic vibration radiator.9 cl, 3 dwg |
