US2018582A - Gas burner or the like - Google Patents

Description

Oct. 22, 1935.

H. THEUNISSEN I GAS BURNER OR THE LIKE Filed May 14, 1952 Patented Oct. 22, 1935 UNITED STATES GAS BURNER OR THE LIKE Herve Theunissen, Charleroi, Belgium Application May 14, 1932, Serial No. 611,341

In Belgium August 6, 1931 3 Claims.

This invention relates to gas burners or the like.

acterized in that the combustible gas is sucked inside a. convergent truncated conical chamber by air which enters this chamber after it has been projected tangentially inside a cylindrical chamber surrounding the device for the admission of gas. T e jet of gas is preferably introduced into the s id chamberin the form of a divergent cone. The cylindrical and truncated convergent chambers may be followed by a divergent truncated conical chamber, which may be followed by a cylindrical chamber, at the end of which the mixture burns.

According to a modification of construction, the mixture is made to penetrate inside a nozzle where secondary air of combustion is admitted in a large number of jets of small diameter, ar-

ranged along a divergent-truncated conical surface and perpendicularly to the latter surface.

The opening or openings for the admission of primary air inside the first mentioned cylindrical chamber may be adjusted so as to vary the 26 thickness of the jet of air which is projected tangentially to the wallof the cylindrical chamber, without varying'its width.

The means for adjusting the said thickness may consist of ;a relative displacement of two concentric cylindrical bodies provided with openings which are displaced upon each other.

The opening or openings for the admission of primary air is or are preferably cut bevel in the substance of the cylindrical body or bodies.

In the accompanying drawing:

Figures 1, 2, and 3 show, by way of example, one mode of carrying the invention into efiect.

In the drawing:

Figure 1 is a longitudinal section of a burner according to the invention.

Figure 2 is a section made along the line 2--2 of Figure l.

Figure 3 isa section made along the line 33 of Figure 1.

5 Referring to the drawing:

A tube I provided with a nozzle I3, which is made adjustable by means of a needle 14 for the injection of gas, opens axially into a convergent truncated conical chamber 3 which forms 60 a prolongation of a cylindrical chamber 2.

The cylindrical chamber 2 is pierced with a rectangular port 1 leaving free passage from a nozzle 6, arranged tangentially on the cylinder 2, for the injection of the air.

55 The adjustment of the width of the port I is A burner according to the invention is chareffected by means of a drum l2 pierced with a hole ill (see Fig. 2) having a cross-section identical to that of the port I and which may be superposed exactly on the latter.

The rotation of the drum I2 inside the cylindrical body 2 allows of varying the section for the admission of air by the relative position of the orifice l0 against the port "I and of varying therefore the thickness of the jet of air which is projected tangentially against the inner .wall 10 of the cylindrical chamber.

It is to be noted that whatever the adjustmentof the opening may be, the cross 'section for the passage of the air is always formed by a slot'of constant width and variable height, 15 according to the position of the drum.

On the other hand, the port I and the orifice I0 are cut bevel in the substance, so as to produce for all the positions a tangential injection of the air into the annular space formed by the 20] cylindrical body of the burner and the tube of injection of combustible gas.

The rotation of the drum l2 inside the body 2 may be actuated from the outside by an Archimedcan screw l5 acting upon a notched sector 25 I6 secured to the drum, or by any other known device. a

The convergent truncated conical portion 3 may be followed by a divergent truncated conical chamber 4 which may be followed by a 30 straight or curved conduit 5 intended to bring the mixture to the place of utilization.

The burner according to the invention may be also constructed as follows:

A nozzle is fixed to the end of the tube 5. 5

The nozzle consists of an outer casing 8 having the shape of a divergent truncated cone, fixed to the tube 5.

concentrically inside the casing 8 is fixed a similar cone 9 made of refractory material or 40 the like, in such a manner as to leave an annular space i5 between the casing and the refractory cone.

The refractory cone is pierced along its entire surface and perpendicularly to the latter, with many holes of small diameter permitting the injection of very finely divided air from the space I5 towards the inside of the cone.

The secondary air of combustion is brought into the peripheral space I5 through a tube ll fixed tangentially upon the casing 8. The tangential arrangement of the tube has for its object to facilitate an even distribution of the pressure upon all the injection holes. 7

The nozzle 8 is used in the case of a two-phase. U

combustion that is when the whole of at air of combustion is not injected into the burner proper. In this case, the additional amount of air is brought through the tube ll into the annular,

space ii at the working pressure and is blown through the refractory cone into the mixture delivered by the tube 5.

At'the outlet of tube 5, without the nozzle 8,

the mixture would spread along acone owing to the strong rotary motion which is imparted to it by the cyclone of air.

This centrifugal 'motion' will have for its eflect to develop the primary mixture along a helicoidal sheet against the refractory done, which sheet is cut in a perpendicular direction by the jets of secondary air.

' The nozzle device 8, added to the burner delindrical chamber I! through the nozzle I, the

needle l4 and mouthpiece l3 'of which, spread the jet in the form of a divergent cone.

It is to be noted that this effect may be obtained by any other known nomle constructions.

The exit speed and the quantityof gas delivered by the nozzle I depend on the opening of the needle and on the pressure of admission of the gas.

The air of combustion is injected into'the chamber 52 tangentially to the inner wall thereof and has a more or less rapid rotary motion, according to its initial pressure. That is, for any quantity delivered by the nozzle I, therefore for any predetermined consumption, the device enables to vary the speed of the cyclone of air by suitably modifying the pressure of admission and the amount of air delivered for a given pressure, by acting upon the opening of the port 1. I

The peripheral'speed of the air is increased according as it advances into the convergent conical chamber where it causes, by its intense centrifugal motion, a suction of the cone of gas from the nozzle i. The. two fluids are intermixed intensely and the mixture penetrates into the cone 4 which sends the mixture, which still has an intense rotary motion.,into the conduit 5 at the outlet of I which it may be allowed to burn, or it may be sent into the nozzle 8 to meet secondary air as above described.

The advantages of the present burner are as follows:

1. It permits of obtaining a perfect mixture of the combustible gas and of the air of combustion.

This allows of obtaining higher temperatures.

2. The burner may work with different quantities of mixture without appreciable variation of the temperature of combustion.

Indeed, for a pre-determined equilibriumtemperature, the suitable proportion of combustion air for each gas delivery of the nozzle l is obtained by regulating the port I. If the pressure of the fan is not modified, the pressure of ad'- mission of the air into the cylinder and conse quently the rotary motion will remain the same, so that whatever its delivery may be, the burner will work with the same two factors: namely same proportion of gas in the mixture and same rotary speed of the mixture.

Since for a gas of given calorific power, the

temperature of combustion results from the said two factors ,'the burner will consequently be able aerate:

to work with different outputs and retain the same temperature of combustion of the mixture.

3. Inversely, the same bumer allows of obtaining a very large scale of temperatures for the same quantity delivered. 5

It is indeed possible by keeping constant the gas delivery of the gas nozzle, to modify within very wide limits, the speed of injection of the air of combustion by adjusting the pressure of the fan for each opening so as to keep constant the amount of air introduced.

4. From the advantages 2 and 3 combined to-' gether, it results that one type of burner may be used within extremely wide limits of tempera'ture and deliveries without reducing the efll- 'ciency of combustion.

5. The intense rotary motion imparted to the mixture in the burner has for its effect to produce at the outlet of the conduit 5 a dispersion of this mixture along a divergent cone, the'opposite of what is obtained with ordinary burners, the flame of which has generally the shape of a convergent cone. 1

This effect is appreciable and has obvious advantages for the heating of reaction chambers of ovens or of combustion chambers and-avoids the well known drawbacks of the converging blow- 6. In the case of a two-phase combustion, that is: (1) partial injection of the combustion air in the burner (primary air) (2) supplementary injection of air into the mixture at the outlet from the burner. (secondary air), which is very'often necessary in metallurgical or other heat treatments, a divergent mixing cone at the outlet from the burner permits of injecting secondary air under much more efllcient conditions.

7. Owing to the fact that the speed of the rotary motion of the mixture may be increased to a large extent, the burner permits of utilizing 40 very rich gases without the danger of back-fire, by the simple adaptation of the speed of injection of the primary air to the speed of propagation of the flame of the mixture.

8. On the other hand, thanks to the perfect homogeneousness of the mixture effected in the burner, the latter gives the possibility of utilizing very poor gases without the risk of extinction.

This nozzle 8 gives the following additional advantages:

(1) it allows of obtaining an atmosphere practically without visible flame at the outlet of the to utilization of gas with very small calorific power.

(3) possibility of heating in a uniform manner chambers of. large volume. I claim:

1. A gas burner having cylindrical chamber to j connected to a convergent truncated conical chamber, the latter being connected to a divergent truncated conical chamber, means for admitting air tangentially inside-the cylindrical chamber, means for admitting gas inside the 76 small jets perpendicular to the surface of the divergent truncated conical chamber.

2. A gas burner having a cylindrical chamber connected to a truncated convergent conical chamber the latter being connected to a divergent truncated conical chamber, means for admitting air tangentially inside the cylindrical chamber through an opening having its sides cut bevel towards the inner wall of the cylindrical chamber, means for admitting gas inside the convergent truncated conical chamber, and means for admitting air through a plurality of small jets perpendicular to the surface of the divergent truncated conical chamber.

3. In a gas burner having a cylindrical chamber, means for admitting air under pressure in a gyratory motion in'the cylindrical chamber, means arranged adjacent the peripheral wall at the cylinder chamber for regulating the air admitted in the cylindrical chamber, a truncated conical chamber connected to the cylindrical chamber and sharply convergent so as to strongly accelerate the gyratory motion of the air, a divergent mixing chamber connected to the truncated conical chamber, means arranged centrally through.

the cylindrical chamber for admitting combustible gas axially at the entrance of the convergent truncated conical chamber, and means for regulating the gas delivery at the entrance of the truncated conical chamber, whereby the air ad-.

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