CA1169753A

CA1169753A - Flame retention burner head venturi for gaseous products and liquids

Info

Publication number: CA1169753A
Application number: CA000435283A
Authority: CA
Inventors: Gerard De Maisonneuve
Original assignee: Individual
Current assignee: MAISONNEUVE GERARD DE
Priority date: 1983-08-24
Filing date: 1983-08-24
Publication date: 1984-06-26

Abstract

ABSTRACT OF THE DISCLOSURE

There is described a combustion system including a cylindrical housing, a burner head in the housing, inlets for air or the like and for combustion products to supply the same to the burner head, mixing and igniting devices for the mixture and a conical baffle to concentrate the combustion mixture toward a short combustion zone. In addition, according to the invention, there is a venturi including a combination valve and disperser which communicates with the conical baffle in order to adjust the amount of combustion products fed to the burner head and to outwardly disperse the same for thorough mixing with the air or the like before the mixture reaches the combustion zone. This system has a substantially improved efficiency over those presently known.

Description

~, ~69 3L31~753 ~ his invention relates to a flame retention burner head for the combustion of liquid and/or gaseous products.
More particularly~ the invention relates to a combustion system for oil or gas in which there is provided a burner head ~hich ensures a better mixture of air and oil or gas, thereby making it possible to improve the combustion efficiency of the heaterO Speci~ically~ the present invention provides a diffu-ser cone or baffle associated with a specially constructed com-bination valve and disperser vrhich substantially improves the combustion efficiency of a combustion chamberO
In an effort to provide a combustion system with higher efficiency7 means have been disclosed which are charac-terized by a more thorough mixing of atomized oil or gas and airO
For example, U.S. Patent No. 2,485,207 proposes the use of a perforated cylindrical tube inside the system, as well as a pump for supplying oil to the nozzle at a predetermined pressure.
This slightly improves the combustion efficiency, but not to a level which would normally be expected of an excellent combus-tion chamber.
U.S. Patent No. 4,313,721 discloses an oil burner dif-fuser which is in the form of a forwardly positioned cone ha-ving a central opening and a series of holes peripherally spa-ced around a central opening. This perforated cone certainly improves the mixing of air and oil or gas, but is still in need of some improvement if a high degree of efficiency is to be a-chieved in the combustion chamber~
Denis Lefebvre,in U.S.Patent ~o.3,733,169 discloses a flameretention headassembly ofthe ~ypeincluding asystem of vanes intended to impart a swinging motion to the air stream rrhich passes through the cylindrical ring provided in the head assem-bly. This swinging air motion of the air stream causes a turbu-lence in the air stream with a resulting improved combustion of the flame produced by ignition o~ the fuel emitted by the nozzle.

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7~3 With the high price of energy, although this system constitutes an improvement over the devices known in the art, it is not suffi-ciently efficient and is therefor in need o further improvement.
U.S. 2,665,748 describes a fuel burner which incor-porates a diffuser cone to provide a better mixing of the fuel and air in order to burn the fuel with greater efficiency.
Although this is an improvement over known burner, the greater efficiency that is proclaimed is still not completely adequate, especially in view of the present cost of fuel. It seems that the mixing although improved is not completely adequate.
Other related art which is considered of interest but is not deemed pertinent includes U.S. 2,247,548 and 2,694,444.
It is therefore an object of the present invention to provide a combustion system whose combustion efficiency is above the presently known systems.
It is another object of the present invention to provide a flame retention burner head enabling an improved combustion of liquid and/or gaseous products.
It is still another object of the present invention to provide a specially constructed venturi including a combination valve and disperser which is associated with a diffuser cone or baffle.
In accordance with the present invention, there is provided 2 system chamber for the combustion of liquid and/or gaseous products including a cylindrical housing, a burner head mounted in the cylindrical housing, means for supplying combustion products to the burner head, means for separately supplying an oxygen-containing gas to the burner head, means to cause mixing and ignition of the combustion products and oxygen-containing gas, and a conical baffle to concentrate the combustion mixture toward a short combustion zone. This -~ system has a combination valve and disperser, means in communication with the conical baffle to adjust the amount of -,~ - 2 -~ 6~ 7~ ~

combustion products fed to the burner head and to outwardly disperse same for thorough mixing with the oxygen-containing gas before the mixture reaches the combustion ~one.
In accordance with a preferred embodiment of the in-vention, the combination valve and disperser means comprises stationary vane means constructed and arranged to cause whir-ling of the oxygen-containing gas and of the outwardly dispersed combustion products thereby additionally improving the mixing of the combustion products with the oxygen-containing gas to give a more efficient burning flame in the combustion zone.
In accordance with yet another embodiment of the in-vention, the oxygen -containing gas supply means is associated with blade means arranged to provide a linear trajectory to the oxygen-containing gas being supplied to the burner head through the conical baffle.
In accordance with yet another embodiment of the in-vention, a tubular member is axially mounted in the cylindrical housing to feed the combustion products to the combustion zone, the tubular member having one end in communication with the com-bustion products inlet~ the other end of the tubular housingbeing connected to the combination valve and disperser means.
The invention will now be illustrated by means of the following non restricting drawings in which, FIGURE 1 is a cross-section view through a combustion chamber according to the invention;
FIGURE 2 is a cross-section view of the combustion valve and disperser characterizing the invcntion, in closed po-sition of the valve;
FIGURE 3 is a view similar to FIGURE 2 showing the opening of the combination valve and disperser;
FIGURE 4 is a perspective view showing the stationa-ry rlhirling blades;

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'7~i3 ~ IGURE 5 is a schematic illustration of the whirling of the combustion products and oxygen-containing gas;
FIGURE 6 is a cross-section view showing the intro-duction of the combustion products, the oxygen-containing gas and the inlet for the secondary preheating device;
FIGUR~ 7 is a front view of the baffle;
FIGURE 8 is a rear view of the baffle;
FIGURE 9 is a view showing a plate in the oxygen-con-taining gas for defining a linear trajectory -to the oxygen-con-taining gas;
~ IGUR~ 10 is a view taken along line 10 - 10 of FIGUR~
9; and FIGURE 11 is a partial view similar to FIGURE 9, with a portion being cut away~ sho~ng the lateral adjustment of a plate~
Referring to the drawings, more particularly FIGURE 1, it will be seen that the system 1 which is il-lustrated includes a cylindrical housing 3, and an inlet 5 com-bined ~th a tubular member 7 for supplying combustion products, such as gas or an oil spray, to the burner head 9. The system 1 also includes an air inlet 11 ( FIGURE 6 ) for se-parately supplying air to the burner head 9, After having tra-velled through the cylindrical casing (inside the tubular member 7 9 in the case of the gas or oil spray) both the air and '~he gas or oil spray meet where they are mixed before reaching the burner head 9 where they ignite. In order to provide a short and effective combustion zone 12, the system 1 com-prises a conical baffle 13 of somewhat standard construction.
This element 13 of the combustion chamber is used to concentra-te the combustion mixture of air and gas or oil toward a shortcombustion zone 12. In addition, and this is what mostly characterizes this invention, the system comprises a ,. .~..

combination valve and disperser 15 which is in communication with the ~nical baffle, The purpose of the combination valve and disperser is to adjust the amount of gas or oil fed to the burner head 9 and to outwardly disperse the mi~ture of oil or gas and air as shovm in FIGURE 1 for a thorough mixlng v~th ad-ditional air before the mixture reaches the combustion zone.
; Having generally described the system 1 according to the invention, with particular reference -~o FIGURE
; 1 of the drawings, a detailed description of the combination valve and disperser 15 will now be made with particular refe-rence to FIGURES 2, 3 and 4 of the drawings~
Beforehand however, it should be repeated that the tu-bular member 7 is axially mounted in the cylindrical housing 3 all in the manner as illustrated in FIGURE 1 of the drawings.
As shovm, this tubular member 7 extends nearly the entire length of the cylindrical housing 3 of the system 1 so as to feed the oil or gas to the combustion zone associated with the burner head 9. Also as shown~ the tubular member 7 has one end 19 in communication lvith the oil or gas inlet 5~ ~rhile the other end 21 of the tubular member is connected to the combina-tion ~alve and disperser 15 vrhich v~ill now be described.
The combination valve and disperser 15 comprises a sleeve 23 having one end 25 threadedly engaged over the threaded end 27 of the tubular member 7. On the other hand, the other end 29 of the sleeve 23 is formed into a toothed edge 31, as particu-larly shovm in FIGURE 4 of the dra~ngs. The combination valve and disperser 15 also comprises a conical outwardly tapering member 33 v~hose smaller end~ as particularly shovm in FIGUR~S

2 and 4 is mounted inside the sleeve 23. Its larger end is for-med into a toothed ring 35 vJhich, as shovm in FIGURE 4 is capa-ble of meshing engagement with the toothed edge 31 of the sleeve 23. FIGURE 2 shows the toothed edge 31 fully engaged with the toothed ring 35, vJhile FIGURE 3 shows the openings 37 formed by disengaging the toothed ring 35 ~rom the ~ully engaged posi-tion illustrated in FIGURE 2~ The mechanism which is used for varying the sizes of the openings 37 by disengaging the toothed ring 37 will now be illustrated v~ith particular reference to FIGURES 1 and 2.
First, it must be pointed out that the disengagement mentioned above is the result of an axial displacement o~ the conical outwardly tapering member 33 relative to the sleeve 23.
This obviously enables to vary the size of the openings 37. In this manner the gas or oil spray which enters through the tubu-lar member 7 outwardly diffuses along the tapering surface 39 of the tapering member 33 and exits from the combination valve and disperser through the openings 37, in adjusted amounts de-pending on the size o~ the openings 37~ Thereafter~ the gas or oil spray is dispersed in the conical baffle 13 for improved mixing with air. For a better distribution of the gas or oil spray pri~r to its entry past the baffle 13 into the combustion zone 12, the tapering member 33 has on its surface 39 three equally spaced radially extending triangular ~ins 41.
To do this~ there is a threaded ring 43 secured in an elbow ~5 connecting the gas or oil inlet 5 and the tubular mem-ber 17. Also, there is a rod 47 which has a threaded portion ~9 ending in a screw head 51 (FIGURE 1) and another threaded por-tion 53 (FIGURE 3). The threaded portion 49 is engaged b~ the threaded ring 43 as shown at the le~t o~ FIGURE 1. The screw head 51 is protected by covering it with a protector cap 55. ~he threaded portion 53 o~ the rod 47 is securedly threaded into a rotatable connector 57 as sho~lm in FIGURE 2. Securing of the 30 threaded portion 53 is made possible by tightening it v~ith tigh-tening screw 59. In addition, there is a bolt 61 whose head 63 is rotatably mounted in kno~m. manner in the rotatable connector 57 all as sholvn in FIGU~S 2 an~ 3. To ena~ f~ee rotation of the rotatable connector 57~ the bolt 61 has a circumferential groove 65 formed therein near the bolt head ~3 and a follovJer 67 is mounted in the rotatable connector 57. The bolt 61 also has a threaded portion 69 which, as sho~m in the same FIG~RES 2 and 3, is threadedly engaged in knovm manner in the smaller end of the tapering member 33. In this manner, when scre~Jing the rod 47 at its screw head 51~ after ha~ing removed the screv~ cap 55~ the rotatable connector 51 is ipso facto rotated and moved toward the combustion zone ~Jhich causes the tapering member 33 to axially move toward the baffle 13 thereby enlarging the ope-nings 37. When unscrewing the rod 47, a reverse operation is carried out to cause reduction of the size of the openings 47.
Although the combination valve and disperser 15 has been found to greatly improve the combustion efficiency, mainly in an industrial furnace~ it vras realised that it was possible to provide still further improvement by creating a whirling of the air and the oil or gas after the latter has been dispersed by the combination valve and disperser 15 which has been descri-bed abo~e. This is made possible by providing the sleeve 23 im-mediately adjacent the toothed adge 31 thereof with a series of outwardly projecting stationary blades 71 which are obliquely mounted and regularly distributed, as particularly shown in FIGU-RE 4 of the drawingsO The blades could be unitary with the slee-ve 23 and toothed edge 31 or the three units can be separate and combined together in knovm manner as shov~ in the drawingsO Il v~ill be seen ~lith particular reference to FIGURES 1 and 5 of the dra~!lings that the series of obliquely arranged blades 71 v~ill cause a r/hirling of the portion of the air v~hich does not enter the combination valve and disperser 15. There is also provided a second series of out~ardly projecting stationary blades 73 im-mediately adjacent the toothed ring 31. ~s in the case of the '7~3 blades 71, blades 73 are also obliquely mounted and regularly distributed, again as shown in FIGURE 4 of the drawings. The blades 73 project from a circular plate 75 which is bolted by means of bolt 77 at the larger end of the taperiny member 33, as shown in FIGURES 2 and 3 of the drawings. This second series of blades 73 will cause a whirling of the oil or gas and some air dispersed by the tapering member 33. The net result, as shown in FIGURE 5, is a deep and thorough mixing of the com-bustion mixture before it enters the combustion zone 12 where an improved combustion efficiency will be obtained. Also illustrated in FIGURE 5 and as shown in FIGURE 1 the system comprises a tapering member 78 which gives a choke effect on the air resulting in a better mixing of the combustion mixture.
In order to still improve the efficiency of the system 1 according to the invention, it has been found that the air which is fed into the system 1 for mixing with gas or oil should travel along a linear trajectory as indicated by the arrows in FIGURE 6 so as to prevent all possible rotation movement thereof. For this purpose, the system 1 has a distributing chamber 79 which is in communication with the cylindrical housing 3 as shown in FIGURES 1 and 6, to feed the air all around the tubular member 17. As shown in FIGURE 6, the inlet 11 laterally leads into the distributing chamber 79. With particular reference to FIGURES 1, 6 and 8 to 11, it will be seen that three radial plates 81 are radially mounted and equally spaced around the cylindrical housing 3. The plates 81 are mounted in known manner such as illustrated in FIGURES 9, 10 and 11 by means of shafts 83 and brackets 85. I~ may be desired to increase or decrease the size of the distributing chamber 79, in which case the plate is - .

~6~'7S3 moved along the shaft 83. Securing of the bracket 85 on the shaft 83 is made possible by means of the locking screw 87.
The operation of the system 1 is conventional except that the sizes of the openings 37 are adjustea depending on the nature of the fuel, temperature desired and efficiency obtainable.
Also conventional is the preheating of the burner head. This can be obtained by providing a secondary gas or oil inlet 89 into the cylindrical housing 3, as particularly shown in FIGURE 1 of the drawings. At the outlet 91 of this fuel duct a combustible mixture is formed which is ignited by the sparking device 93. This produces a secondary combustion zone which preheats the burner head and facilitates ignition of the combustion chamber.

g _ ~g7~;3 SUPPLEMENTARY DISCLOSURE

It has also been found that it may'be desired to dispense with the conical baffle.
FIGURE 12 is a perspective view similar to FIGURE 4 which is associated with a choking device.
In the case illustrated in FIGURE 12, the air is directed toward the combustion mixture exiting from the venturi by means of choke-type tapering member 95.

Claims

The embodiments of the invention in which an exclu-sive property or privilege is claimed are defined as follows:

1. In a system for the combustion of liquid and/or gaseous products including a cylindrical housing, a burner head mounted in said cylindrical housing, means for supplying combustion products to said burner head, means for se-parately supplying an oxygen-containing gas to said burner head, means to cause mixing and ignition of said combustion products and said oxygen-containing gas, and a conical baffle to concen-trate combustion mixture toward a short combustion zone, the improvement which comprises a venturi including combination valve and disperser means in communication with said baffle to adjust the amount of combustion products and oxygen-containing gas fed to said burner head and to outwardly disperse same for thorough mixing with additional oxygen-containing gas before the mixture reaches the combustion zone.

2. A system according to claim 1, wherein said combination valve and disperser means comprises stationary vane means constructed and arranged to cause whirling of oxygen-containing gas and of the outwardly dispersed combustion products thereby additionally improving the mixing of the combustion pro-ducts with the oxygen-containing gas to give a more efficient burning flame in the combustion zone.

3. A system according to claim 2, wherein the oxygen-containing gas supply means is associated with blade means arranged to provide a linear trajectory to the oxygen-containing gas being supplied to the burner head through the co-nical baffle,

4. A system according to claim 2, which comprises a tubular member axially mounted in said cylindrical housing to feed said combustion products to said combustion zone said tubular member having one end in communication with a com-bustion products inlet, the other end of said tubular member being connected to said combination valve and disperser means.

5. A system according to claim 4, wherein said combination valve and disperser means comprise a sleeve having one end threadedly engaged over the other end of said tubular member, the other end of said sleeve being formed into a toothed edge, a substantially conical outwardly tapering member whose small end is mounted inside said sleeve and whose larger end is formed into a toothed ring which is capable of meshing engagement with the toothed edge of said sleeve to provide variable size openings therebetween, and means to cause axial displace-ment of said conical outwardly tapering member relative to said sleeve, thereby varying the size of said openings whereby said combustion products entering through said tubular member out-wardly diffuse along said tapering member and exit from said combination valve and disperser through said opening in adjusted amounts as a result of said axial displacement of said tapering member, to be dispersed in said conical baffle for improved mixing with said oxygen-containing gas.

6. A system according to claim 5, wherein said stationary vane means comprises a first series of outwardly projecting stationary blades obliquely mounted and regularly distributed on said sleeve adjacent said toothed edge along the entire periphery thereof, and a second series of similar out-wardly projecting stationary blades obliquely mounted and regular-ly distributed on said ring adjacent the toothed portion thereof along its entire periphery, said first series of stationary blades causing a whirling of some oxygen-containing gas and said second series of stationary blades causing whirling of said com-bustion products, and also some oxygen-containing gas.

7. A system according to claim 6, which comprises a plurality of radially extending substantially trian-gular fins longitudinally mounted on said tapering member for better distribution of said combustion products through said openings and into said system prior to entering said combustion zone.

8. A system according to claim 7, which comprises an oxygen-containing gas distributing chamber which is in communication with said cylindrical housing to feed an oxygen-containing gas therein all around said tubular member, a duct laterally leading into said distributing chamber for introducing an oxygen-containing gas therein, and radial plates longitudinally mounted in said distributing chamber so that said oxygen-containing gas will adopt a linear trajectory without substantial rotatory motion while being fed into said casing.

9. A system according to claim 8, wherein the means to cause axial displacement of the outwardly tapering member comprise a threaded ring secured at said one end of said tubular member, a rod having a first threaded portion at one end and a second threaded portion at the other end, the first threaded portion being engaged by said threaded ring, a rotatable connec-tor having the second threaded portion of said rod securedly threaded therein so as to rotate upon rotation of said rod, a bolt whose head is rotatably mounted in said rotatable connector and whose threaded portion is fixedly threaded in said tapering member, so that when screwing said rod, said tapering member is axially moved toward said baffle to enlarge said openings and unscrewing of said rod causes reduction of the size of said ope-nings.

10. A system according to claim 1, which comprises a secondary combustion gas inlet into said cylindrical housing and a sparking device near the end of said gas inlet to produce a secondary combustion zone to preheat said burner head.

CLAIM SUPPORTED BY THE SUPPLEMENTARY DISCLOSURE

11. In a system for the combustion of liquid and/or gaseous products including a cylindrical housing, a burner head mounted in said cylindrical housing, means for supplying combustion products to said burner head, means for separately supplying an oxygen-containing gas to said burner head, means to cause mixing and ignition of said combustion products and said oxygen-containing gas, and means to concentrate combustion mixture toward a short combustion zone, the improvement which comprises a venturi including combination valve and disperser means associated with the concentrating means to adjust the amount of combustion products and oxygen-containing gas fed to said burner head and to outwardly disperse same for thorough mixing with additional oxygen-containing gas before the mixture reaches the combustion zone, said concen-trating means comprising a choke mounted outwardly of said venturi and inwardly tapering to direct air toward said short combustion zone.