SU745562A1 - Ultrasonic plant for liquid treating - Google Patents

Description

I

The invention relates to ultrasonic technology and can be used in ultrasonic technological installations for cleaning parts from technological contaminants, for dispersing, enameling, impregnating, mainly in mechanical engineering, chemical, light and other industries.

The device contains ultrasonic treatment plants for liquid processing, containing a camera with an ultrasonic transducer embedded in it and sound-suppressing elements with an acoustically rigid surface in the form of a goat mounted outside the ka-. measures lj and in the form of a bottomless cylinder, placed inside an ultrasound chamber

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Ultrasonic devices with such noise suppressing elements have a Q-lower level of airborne noise caused by the vibrations of the walls of the chamber itself, excited by the cavitating working fluid, but the noise level emitted by the working fluid mirror in such chambers is not reduced. ,

This disadvantage is eliminated in ultrasonic chambers with noise suppressing elements in the form of an acoustically rigid substrate with a sound-absorbing coating located in their upper part, such materials as foam rubber, acigrane, ultra-thin basalt fiber or glass fiber, etc. are used as sound absorbing coating. The noise-damping element can be plugged out in the form of a nozzle cover 1.4.

This design of ultrasonic units with noise-attenuating elements, although it has a reduced noise level, has the disadvantage that it does not always give a sufficient amount of noise reduction to the value due to sanitary standards, especially at high ultrasound intensities, causing cavitation to increase and collapse intensity cl vitation bubbles. him too

745562 the design is unreliable, as under conditions of steam heated to 80 ° and strong, sometimes aggressive (acids, alkalis, organic solvents) in relation to the sound-absorbing working fluid of the material, the sound absorbing coating due to moisture absorption, exposure to aggressive working fluid and from drying out (if it is dry) loses its sound-absorbing properties much earlier than the lifetime of the camera itself. Therefore, the ultrasonic operating conditions are complicated. At the same time it comes with cleaning the sound-absorbing coating to dry or change it. Often there is a need to attach a 6qpT suction suction to the ultrasonic sound chamber so that the working fluid does not float into the surrounding space. An airborne suction unit must be attached over the noise-blocking element of the chamber in order to reduce the radiation of the noise into the surrounding space. This complicates the design of the camera and increases its size. In the case of airborne suction directly above the level of the working fluid (before the noise damping element), the noise from the chamber enters the ventilating system and measures must be taken to protect against it. Dimensions of the camera at the same time increase. The purpose of the invention is to reduce the level. -. ,, The goal is achieved by the fact that in the well-known ultrasonic liquid treatment plant, which contains the GtcTpoeHtibTM camera into its ultrasonic device; About the user and the noise-suppressing element located in the upper part of the chamber in the form of an acoustically rigid substrate with a sound-absorbing coating, there is a hole in the acoustically rigid substrate, whose entrance is located on the side of the sound of the covering. Such a decay of the ultrasonic equipment allows one to significantly reduce the level of the shuma it causes due to better matching of the acoustic resistance of the substrate and the sound-absorbing coating. The holes in the acoustically rigid substrate can accommodate a different truss of a round, square heel and grooves. П | Гв вА6ш1енв отвергйВ without through х х depth of berets equal to a quarter of the wavelength of the muffled sound in the air. When ogam is obtained, the best matching of the acoustic impedances of the system is the air-sound-absorbing coating and a rigid substrate. In an acoustically rigid substrate, the noise-clip element is made through with a depth equal to half the wavelength of the muffled sound in air, thereby also achieving the best matching of the acoustic impedances of the system. In order to increase the effect of noise suppression, the holes in the acoustically rigid substrate are made by the noise damping element so that their axes are non-perpendicular 1 to the acoustically rigid substrate. This arrangement of the holes makes them, as it were, a trap for sound waves, i.e. increases the length of their path, as well as quantities in reflections from the walls of the holes. An increase in the path of zolotsov waves and an increase in the number of their reflections inside the noise suppressing element enhances the effect of noise suppression. The sound-absorbing coating of the noise-suppressing element is made in the form of a metal grid, which makes it possible to eliminate the use of 1-type sound-absorbing coatings made of foam rubber, basalt or glass cloth, etc. At the entrance of non-through, quarter-wave holes, as well as on the Code and the through holes of the half-wave depth is the maximum of the oscillatory velocity of air particles. The metal mesh covering the holes dampens the velocity of the particles and introduces diosipative losses, i.e. The functions of the sound-absorbing coating. To do this, you can use a wire mesh with a diameter of Ø 0.05 mm, in increments of 0.12 mm. It is also possible to use a grid with a larger W (ar, but put it in several layers to achieve the effect of reducing the vibrational velocity of air particles. If it is necessary to use a side suction in the ultrasonic chamber, it is located not above the noise suppressing element as usual, but with the aim of Neither the chamber structure nor the reduction of its dimensions is mounted on the outer side of the silencing element. At the same time, the acoustically rigid substrate of the noise suppressing element is made with through holes, 1 from both Metal mesh. Such suction reduces the level of noise propagating into the ventilation system with the system due to its passage through the body; from the substrate of the sounding element of the specified design. In addition, on the side of it, it plays the role of an additional casing surrounding the sound attenuating element and Fig. 1 and 2 depict the proposed ultrasound unit for liquid processing; 3, 4, bibsaPanes are options for making holes in an acoustically rigid substrate of a sound-attenuating element. The device consists of a chamber 1 with a transducer 2. An acoustic sound substrate of the noise suppressing chamber element | located above the level 3 of the working fluid 4, is made with two orbital holes 5. The apertures are grooves with a depth equal to one quarter of the wavelength of the muffled sound in the air. The acoustically stiff substrate of the noise-attenuating element can be made with through-holes 6 with a depth equal to half the wavelength of the muffled sound in the air. To this part of the noise-suppressing element with through holes 6 is attached a side suction 7. The holes in the substrate of the noise-suppressing element are covered with a metal grid 8. The axes of the holes 5 and 6 are made to the plane of the acoustically rigid substrate at an angle not equal to 9O. . 3, 4, 5, 6 shows examples of holes in an acoustically rigid substrate of a noise-suppressing element: nonstop {FIG. 3 and FIG. 5) a depth equal to one quarter of the wavelength of the muffled sound in the air, and through (Fig. 4 and Fig. 6) depth equal to half the wavelength of the muffled sound in the air. The arrows indicate the directions of propagation of sound waves. The device works as follows. The chamber is filled with working fluid 4 (FIG. 1) and includes ultrasound. In this case, the liquid begins to cavitate and radiate the cavitation noise by a mirror. Due to the presence of a sound-suppressing element in the form of an acoustically rigid substrate with a sound-absorbing coating with 5 willows in the substrate, and thanks to a metal mesh coating 8 (or coatings of sound-absorbing material), a more effective noise damping is achieved than in lEiBacrw

6 direct installations. The holes in the substrate of the noise-reducing element reduce the acoustic resistance of the substrate and bring it closer to the acoustic resistance of both the sound-absorbing coating and air, which increases the effect of reducing noise. Completion of blind holes with a depth equal to the invert, and through depths equal to half the wavelength of the muffled sound in the air, make the effect of reducing the acoustic resistance of the sound suppressor element more significant compared with the option of making holes of arbitrary depth, since the input resistance is minimal for these cases. The level of noise emitted by the mirror 3 of the liquid 4 and penetrating into the side of the bay 7 is also reduced due to the passage of the sound wave through the holes b covered with a grid 8. As can be seen from FIG. 5 and 6, the apertures serve as traps for sound waves, i.e. increase the path length and the number of collisions of sound waves with the substrate of the sound-damping element. Increasing the length of the sound waves and increasing the number of Si collisions inside the structure leads to more effective sound absorption. Using the proposed ultra sound installation for liquid processing, containing a camera with a sound-suppressing element in its upper part in the form of an acoustically rigid substrate with holes drilled in it allows to reduce the level of noise emitted in the air. The effect of noise absorption is enhanced by making holes of a certain depth. Through - half-wave, non-through - quarter-wave depth and when performing holes in such a way that their axes are not perpendicular to the acoustic substrate. Use as a sound-absorbing coating for metal mesh increases the reliability of the design and improves the operating conditions of the installation. The on-board suction of the chamber is connected to the outside by the noise of the damping element, the acoustically rigid substrate of which is made with squash openings covered with a metal mesh, reduces the size of the device and gives an additional decrease in the level of Noise propagating from the chamber in cTqpoHy ventilation and surrounding sreru.

Claims (6)

Claim 1. Ultrasonic installation for liquid processing, containing a camera, built-in ultrasonic transducer. a separator and a sound attenuation element located in the upper part in the form of an acoustically rigid substrate with a sound-absorbing coating, characterized in that, in order to reduce the noise level, openings are made in the acoustically-rigid substrate, the inlets of which are located on the side of the sound-absorbing coating. 2. Installation according to πί · 1, which entails that the holes are made blind with a depth equal to a quarter of the wavelength of sound in air. 3. Installation according to π. 1, distinguished by the fact that the holes are made through with a depth equal to half the wavelength of sound in air. ts 4. Installation according to paragraphs 1,2,3, with the fact that the holes are made so that their axes are not perpendicular to the acoustically rigid substrate. 5. Installation according to claims 1, 2, 3, 4, characterized in that the sound-absorbing coating is a metal mesh. 6. Installation according to paragraphs. 1, 3, 4, 5, which is relieved by the fact that it is equipped with a suction mounted on the outside of the noise-attenuating element.