US2700576A - Apparatus for atomizing liquids - Google Patents

Description

1955 F. sALsAs-sERRA ET AL 2,700,576

APPARATUS FOR ATOMIZINC LIQUIDS Filed Oct. 29, 1952 ZNVENTORSI United States Patent APPARATUS FOR ATOMIZING LIQUIDS Francisco Salsas-Serra and Antoine Planaguma, Paris, France Application October 29, 1952, Serial No. 317,551

Claims priority, application France October 30, 1951 2 Claims. Cl. 299-63) The known methods and apparatus for mechanical atomization of liquids can be classed into three groups:

(a) Atomization using air or gases under pressure.

(17) Atomization by compression of liquid.

(0) Atomization by centrifuging and impact.

In the first group, the effect of expansion of compressed gases which emerge from a tube which is concentric or in a position normal to the arrival tube for the liquid, drives the liquid at the same time as, by the effect of the great speed of the gaseous current, reducing it to very fine particles. Because of this fact, the atomized liquid is mixed intimately with-the gases. The amount discharged and the fineness of atomization are a function of the pressure and amount discharged of the gases. In general, the apparatuses belonging to this group are employed when the quantity of liquid to be atomized is very small with respect to the volume of gas.

In the second group, the liquid is sent at high pressure through an orifice with thin walls, or any otherdevice, in such a manner as to create a turbulent flow. At the exit of the orifice, the liquid stream bursts into fine droplets under the action of bombardment of molecules in turbulent movement. It is diflicult to obtain a great average fineness of atomization by the apparatuses belonging to this second group. Also, the quantity of energy necessary is very high.

In the third group there are found the apparatuses which bring about atomization of liquids either starting with the well-known principle of dispersion of a liquid which falls onto a rotating surface, at high speed, or by projection against fixed or moving impact surfaces; so far as the first are concerned, satisfactory results are only obtained when the quantity of liquid to be atomized is small and the speed of rotation very high, which necessitates the employment of apparatuses of high cost and small energy yield. As far as the second are concerned, they generally have difficulties in obtaining a good dispersion of the liquid at the impact surfaces which gives rise, above all if the discharge quantity is large, to an irregular fineness of atomization, to jamming up of the liquid at the points where it strikes, preventing the obtaining of the effect sought.

The method which is the object of the present invention utilizes the pressure of the liquid to communicate to the latter laminar-flow kinetic energy through one or more orifices in order to obtain perfect dispersion of the liquid on a series of perforated surfaces in rotation in each of which only a part of the liquid undergoes the impact action which gives rise to its atomization, the other jet or remainder of the jets conserving their kinetic energy in order to act progressively on the succeeding rotating perforated surfaces, until there is complete atomization of the liquid.

An important characteristic of this method consists in causing centrifugal force to act on the atomized liquid immediately after the impact, without breaking into the kinetic energy of the non-atomized liquid, in order to rapidly evacuate the mist formed from the zone of atomization.

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It will be understood that by adjusting the speed and quantity discharged of the liquid with respect to the number and peripheral speed of the impact surfaces, and to the dimensions and proportions of the full parts and perforated parts of these surfaces, there can be obtained the complete and extremely full atomization of a predetermined discharge quantity of liquid.

The accompanying drawing shows by way of nonlimiting example a construction of the invention.

Figure 1 shows a view of the apparatus in elevation and in partial section; Fig. 2 is a view in plan of one of the crenellated rotary elements.

In these figures, 1 is the plate supporting the whole, 2 is the hollow column supporting the motor 3 and in which arrives, at 4, the liquid to be atomized, 5 is a centrifugal turbine keyed on the shaft 6 of the motor 3 and which sends the liquid under pressure towards the periphery of the chamber 7, from whence it is projected vertically through the orifices 8 onto the crenellated external part of the disks 9 likewise driven by the shaft 6.

In rotating, each blade 10, of which the forward edge is preferably slightly raised, crosses in some way the jets of liquid projected through the orifices 8 whilst violently impacting and projecting towards the exterior an infinitesimal part of these jets, the rest of which is thereafter impacted by the blades 10 of the disks 9 taken successively in the downward direction.

It will be well understood that the construction described and shown above is only by way of example and could vary without departing from the scope of the following claims.

We claim:

1. An apparatus for atomizing a liquid comprising a centrifugal turbine, driving means therefor, means for feeding liquid axially to said turbine, a casing positioned about the turbine and spaced radially therefrom to form an annular channel for receiving liquid thrown radially outwards by the turbine, a series of nozzles in the casing communicating with the channel and arranged to direct linear jets of the liquid parallel to the axis of the turbine, and a series of disks rotated in parallel planes normal to the path of the jets, each said disk having a series of alternate openings and solid portions and the series of disks being positioned with respect to the jets such that the jets alternately impinge on the solid portions and pass through the openings as the disks are rotated.

2. An apparatus for atomizing a liquid comprising a rotary shaft, driving means therefor, a centrifugal turbine mounted on the shaft, means for feeding liquid axially to the turbine, a casing positioned about the turbine and spaced radially therefrom to form an annular channel for receiving liquid thrown radially outwards by the turbine, a series of nozzles in the casing communicating with the channel and arranged to direct linear jets of the liquid parallel to the axis of the rotary shaft, and a series of disks mounted on the rotary shaft for rotation in parallel planes normal to the path of the jets, each said disk having a series of alternate openings and solid portions and the series of nozzles in the casing being so positioned that the jets alternately impinge on the solid POItlOlS and pass through the openings as the disks are rotate References Cited in the file of this patent

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