Cavitation mixer

Abstract

The subject of the utility model is a cavitation mixer. The field of application is the food, chemical, petrochemical and other industries where cavitation mixing can be used. The essence of the utility model is a cavitation mixer comprising medium inlet and outlet pipes, a cylindrical flow chamber and a cavitator mounted therein, movable in the axial direction and on the axis, in the form of a truncated cone, with its smaller base facing the flow and having pyramidal slots located at an acute angle to its axis and directed with their apex towards the flow, and a hollow conical nozzle, with its larger base facing the cavitator, the sides of the pyramidal slot, located at an acute angle, are made with brachistochrone surfaces. The technical result is increased efficiency of cavitation mixing.

Description

[0001] The utility model relates to devices for producing emulsions and suspensions in a hydrodynamic cavitation field and can be used in the food, chemical, petrochemical and other industries.

[0002] A cavitation hydrodynamic mixer is known, containing a flow chamber with pipes for supplying and removing the medium being processed, and a stationary cavitator installed in it in the form of a truncated cone having pyramidal slots [USSR A.s. No. 1349057. IPC B01 F 5 / 00. Hydrodynamic mixer. Published 10.10.1997.].

[0003] This device does not achieve high mixing efficiency, since the cavitation cavity formed behind the stationary cavitator in the diffuser is not long enough to collapse the liquid bubbles.

[0004] A cavitation mixer is known, comprising pipes for inlet and outlet of the medium, a cylindrical flow chamber and an axially movable cavitator installed therein in the form of a truncated cone, with its smaller base facing towards the flow, and an empty conical nozzle with its larger base facing the cavitator [USSR A.S. No. 1790438. IPC B 01 F 5 / 00. Cavitation mixer. / O.V. Kozyuk, A.A. Litvinenko. - Published 21.01.93. Bulletin No. 3; Patent. UA No. 1017. IPC B 01 F 5 / 00. Cavitation mixer. / O.V. Kozyuk, A.A. Litvinenko. - Published 31.05.93].

[0005] However, the use of the known cavitation mixer does not allow changing the position of the cavitator to achieve the necessary hydrostatic pressure in the conical nozzle to form the growth of cavitation bubbles, high intensity of the cavitation field, and, therefore, achieve high mixing efficiency.

[0006] A cavitation mixer is known, selected as a prototype, containing pipes for inlet and outlet of the medium, a cylindrical flow chamber and a cavitator in the form of a truncated cone, movable in the axial direction and on the axis, installed in it, with its smaller base facing the flow and having pyramidal slots located at an acute angle to its axis and directed with their apex towards the flow and a hollow conical nozzle, with its large base facing the cavitator [Patent. UA No. 31086. IPC B 01 F 5 / 00. Cavitation mixer. / A.V. Gvozdev, V.O. Gvozdev, L.I. Mazurik. - Published. 03.25.2008. Bulletin No. 6].

[0007] The use of the known cavitation mixer also does not allow changing the position of the cavitator to achieve the necessary hydrostatic pressure in the conical nozzle to form the growth of cavitation bubbles, high intensity of the cavitation field, and, therefore, achieve high mixing efficiency.

[0008] The utility model is based on the task of improving a cavitation mixer by combining the effects of swirling liquid flows in the pyramidal slots of a conical cavitator due to special surfaces and its intensive rotation around an axis, which ensures the creation of a continuous swirling cavitation field of increased activity of the processed medium, thereby increasing the efficiency of cavitation mixing.

[0009] The stated problem is solved in that in a cavitation mixer containing pipes for supplying and discharging a medium, a cylindrical flow chamber and a cavitator installed in it, movable in the axial direction and on the axis, in the form of a truncated cone, with its smaller base facing the flow and having pyramidal shaped slots located at an acute angle to its axis and directed with their apex towards the flow and a hollow conical nozzle, with its large base facing the cavitator, according to the utility model, the sides of the pyramidal slot, located at an acute angle, are made with brachistochronic surfaces.

[0010] Such a combination of essential features as the implementation of pyramidal slots in a conical cavitator, located at an acute angle to its axis with brachistochronic surfaces and directed with their apex towards the flow, creates additional cavitation caverns when ejecting liquid jets through the slots due to the increase in the speed of descent of the mixed liquid from the brachistochronic surfaces (brachistochronic surfaces allow for the maximum speed of descent of material particles from them with a minimum friction coefficient. Vasilenko P.M. Theory of particle motion on rough surfaces of agricultural machinery.: K. Publishing House of the Ukrainian Academy of Agricultural Sciences. - 1960), which contributes to an increase in the concentration of bubbles per unit volume of the mixed liquid.The presence of slots with brachistochrone-shaped surfaces in the cavitator creates additional torque for the rotating motion of the cavitator when jets of liquid are ejected through the slots, which creates a mechanism for additional mixing of the liquid during its cavitation in the void of the conical nozzle.

[0011] The essence of the proposed utility model is explained by drawings, where

[0012] Fig. 1 shows the claimed cavitation mixer, longitudinal section;

[0013] in Fig. 2 - cavitator;

[0014] in Fig. 3 - view A in Fig. 2.

[0015] The cavitation mixer consists of a cylindrical flow chamber 1, in which, for example, a cavitator 3, shaped like a truncated cone with its smaller base facing the flow, is mounted on an axially movable rod 2 and rotated. Cavitator 3 has pyramidal slots 4, located at an acute angle to its axis and oriented with their apex facing the flow. The sides of the pyramidal slot 4, located at an acute angle, have brachistochrone-shaped surfaces 5.

[0016] Behind the cavitator 3 in the flow chamber 1, a hollow conical nozzle 6 is placed, with its large base facing the cavitator 3. The diameter of the large base of the nozzle 6 is equal to the diameter of the flow chamber 1. The nozzle 7 and nozzle 8 are used, respectively, to supply the processed medium to the mixer and to remove it from it.

[0017] The cavitation mixer works as follows.

[0018] The liquid being processed enters flow chamber 1 through inlet pipe 7 and flows onto cone-shaped cavitator 3, located within it and facing the flow with its smaller base. The liquid streams, entering pyramidal slots 4, swirl and, due to the increased velocity of their descent from brachistochrone-shaped surfaces 5, create a cavitation flow regime, causing the cavitator to rotate, creating cavitation cavities that move along a helical line and generate a field of cavitation bubbles that saturate the flow throughout the entire volume of flow chamber 1 of the mixer. Since a hollow conical nozzle 6 is placed behind the cavitator 3 in the flow chamber 1, with its large base facing the cavitator 3, and the diameter of the large base of the nozzle 6 is equal to the diameter of the flow chamber 1, a two-phase swirling flow containing distributed cavitation bubbles enters the inlet of the nozzle 6.In nozzle 6, the flow velocity increases significantly due to compression, causing a further decrease in hydrostatic pressure. Under these conditions, cavitation bubbles do not collapse but begin to expand before exiting nozzle 6, forming a stable two-phase flow with fairly large cavitation bubbles at the outlet. Collapsing cavitation bubbles form pulsating shock waves and cumulative microjets, which exert an intense mixing effect on the process medium. The size of the cavitation bubbles is influenced by both the residence time in the low-pressure zone and the ratio of the outlet opening of nozzle 6 to cavitator 3. By moving cavitator 3, mounted, for example, on rod 2 along the axis of flow chamber 1, the distance from cavitator 3 to nozzle 6 can be varied, thereby regulating the length of the rotating cavitation cavity.

[0019] The liquid medium processed in the cavitation mixer is removed from it through the outlet pipe 8.

[0020] The use of the claimed technical solution for obtaining emulsions and suspensions in a hydrodynamic cavitation field makes it possible to increase the mixing efficiency by creating a continuous rotating cavitation field of high activity.

Claims

A cavitation mixer comprising pipes for supplying and discharging a medium, a cylindrical flow chamber and a cavitator in the form of a truncated cone, movable in the axial direction and on the axis, installed in it, with its smaller base facing towards the flow and having pyramidal shaped slots located at an acute angle to its axis and directed with their apex towards the flow, and a hollow conical nozzle, with its larger base facing towards the cavitator, characterized in that the sides of the pyramidal slot, located at an acute angle, are made with brachistochronic surfaces.

Images