US2676649A

US2676649A - Turbulator

Info

Publication number: US2676649A
Application number: US292932A
Authority: US
Inventors: Gordon H Diehl; Robert M Hopkins
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1952-06-11
Filing date: 1952-06-11
Publication date: 1954-04-27
Anticipated expiration: 1971-04-27

Description

April 27, 1954 G. H. DIEHL ET AL 2,676,64

TURBULATOR Filed June 11, 1952 f1? van zars Gordon H Die/5] Robert M Ha 101 75 1 Z By P Wm, My? 2775]) fizfarneys Patented Apr. 27, 1954 Gordon H. 'Diehl and Robert M. Hopkins, Rochester, N. Y. 'assignors to General Motors Corporation,'Detroit, 'Mich., a'corporation of Delaware Application .lunell, 1952, Serial No. 292,932

6 Claims.

This invention relates to oil burners and has to do with providing a combustible mixture of liquid fuel and air for eflicient heating purposes.

The present invention is best adapted to oil burners having an hourly rate of fuel consumption of approximately 1.25 to 1.65 gallons per hour but is not limited to this range.

Itis particularly adapted to oil burners of the pressure atomizing type wherein air is supplied by a blower to a draft tube which is outfitted centrally with a fuel line terminating in an atomizing nozzle and an electric igniter mounted close to the nozzle. Conventionalpressure atomizing oil burners are of this general construction.

Many and complicated devices have been used hitherto in an attempt to mix the air in the drafttube with the atomized fuel coming from the nozzle so that combustion will be asnearly complete as possible. In actual practice an oil burner should be quietin operation, combustion should be as nearly complete as possible to avoid formation of soot and the flame should be stable under various conditions of application such as variations in the construction and operation of the chimmey or stack.

7 It is an object of the present invention to achieve these desirable features in a simple manner.

panying drawings wherein a preferred embodiment of the present invention is clearly shown.

In the drawing; g Fig. 1 is a partial sectional view of the fuel discharge end of an oil burner draft tube assembly.

Fig. 2 is a sectional view of the burner draft tube assembly on line 22 of Fig. 1. I

With particular reference to the drawings l0 refers to a draft tube that is designed to conduct air under pressure to thefinterior of the furnace, and I2 is an oil pipe fitted with a nozzle adapter I4 provided with an atomizing nozzle l6 designed to deliver fuel inatomized form, in a cone of mist somewhat as indicated at l8. In-

: sulators 20 support electrodes 22 that extend to close proximity of cone [8 of atomized fuel. The

atomized fuel I8 is ignited by a spark at the end of electrodes 22 and after the spark is shut off the cone of fuel will continue to burn as long as p the fuel supply is maintained.

Air from the tube l0 must be mixed with the cone of fuel I8 and the manner in which thisis brought aboutis a subject of the present invention. In this instance a turbulator 24 incorporates a bushing 26 disposable over the oil pipe I2 where it may be secured by a set screw 28 and cooperates with a set screw 30 passing through

clip members

32, and 34 for supporting the insulators 20 of electrodes '22. A hub 35 of bushing 26 passes through an aperture in a head member 36 where it is secured as at 38.

The head member 36 is also apertured for passage of insulators 20 but is otherwise'impervious.

The head member 36 provides a closure for a cylindrical drum 4!] of the turbulator proper.

The drum 40 is provided byr'olling up a blank of sheet metal to provide a cylinder for surrounding the fuel nozzle and electrodes, with the fuel nozzle disposed centrally thereof. f The blanking of the cylinder comprises shearing on three sides of a rectangle to provide longitudinally extending openings 43 within vanes or fins 42 bounded around three edges by

short end portions

44 and 46 connected by free edge 48.

This sheared'portion or vane 42 is left flat so as'to extend as a tangent from the root portion 50 when the blank is rolled into a cylinder.

Rectangular openings 64 are arranged in one end 'of the drum with their centers coinciding with the general plane at the tip end of the nozzle l6. These openings 64 are arranged at the outer end of the drum and in the root portion of the vanes 42, that is to say, they are generally centered about the line joining the unsheared portion of the vanes. When rolled that leaves

cylindrical bands

52 and 54 at each end of the turbulator with outwardly finned portions 42. The end of the cylindrical band 52 is bonded to the head member 36 and the cylindrical band 54 is piloted in a central aperture 56 of an end plate 58. v

Angle brackets '60 secured to the end plate 58 are receptive of screw devices 62 for mounting the end plate 58 at the end of the draft tube Ill.

A frusto conical deflector 66 is provided witha flange 68 which is bonded to the plate 58.

flows through the apertures 10 directly into the combustion chamber.

The air which flows beneath the vanes 42 passes into the drum 40 and sets up the equivalent of a cyclone within the drum. This stream of air moves forward in the drum to its open end and in the course of its passage mixes with the cone of atomized fuel l8. It is deflected somewhat toward the cone of fuel by the deflector 66. A thorough mixing of air and fuel is thereby attained.

The air which flows through the openings 64 is believed to pass almost radially into the drum 40 and the purpose of this air stream is to reduce the noise of the burner flame. It is practically impossible to determine just what takes place but tests show a marked reduction inflame noise.

The air which flows through the apertures 10 passes into the combustion chamber, not shown, and mixes with the flame coming from the burner. This stream of air further reduces the flame noise.

Burners have been tested using the construction herein disclosed and it was found possible to burn fuel oil with a 13% CO2 flue gas content and with a very low soot deposit. The flame was very stable under varying draft conditions and the burner operation was quiet.

While the embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted.

What is claimed is as follows:

I. In an oil burner having a draft tube and an oil atomizing nozzle for 'eifecting combustion of a liquid fuel, a turbulator disposed at the exit end of the draft tube and "encompassing said fuel nozzle, said turbulator comprising a cylindrical cup having openings and exterior fins adjacent thereto admitting air tangentially from the draft tube to the region of the fuel nozzle along a gyratory path, said turbulator having surface openings located in the roots of said fins admitting air along radial paths from the draft tube substantially in the plane of said fuel nozzle, whereby the air in the draft tube passing thru the turbulator is mixed with the atomized fuel to provide a combustible mixture, and plate means closing the end of the draft tube and supporting one end of the turbulator, said plate means having openings permitting restricted lineal flow from the draft tube and for creating a pressure head for the tangential flow and the radial flow from the draft tube to the interior of the turbulator.

Z. In an oil burner, a draft tube, an oil pipe and fuel nozzle centrally disposed in the draft tube, a turbulator supported by the oil pipe and circumscribing the fuel nozzle, an annular plate across the space between the turbulator and draft tube, said annular plate having a series of apertures permitting restricted air flow from the draft tube, said turbulator comprising a cylindrical portion having openings bordered by exterior fins admitting air into the turbulator back of the fuel nozzle, and having openings thru the roots of said fins in the region'of said fuel nozzle for admitting radially moving air to the interior of said turbulator for mixing with the tangentially admitted air to effect air currents of maximum turbulence in the region of fuel discharge from said nozzle, and a frusto conical deflector supported by the annular plate separating the lineal moving air from the turbulated moving air and for deflecting the latter toward the fuel nozzle insuring a combustible mixture in front of the fuel nozzle.

3. In an oil burner, a draft tube providing a directed flow of air for supporting combustion, a fuel pipe supported at the axis of said draft tube and provided with a fuel nozzle at the normally open end of said tube, a turbulator supported by the oil pipe and disposed about said fuel nozzle, an annular head member supported by the end of the draft tube and spanning the space between the draft tube and the turbulator, said turbulator comprising a cylindrical drum piloted in said annular head member and having circumferentially spaced openings, a head member closing the other end of the drum and said drum having longitudinal openings bounded on one side thereof by tangentially extending fins struck outwardly from the surface of said drum for admitting air in a swirling motion to the interior of said turbulator and on the rear side of said fuel nozzle, and a circumferential series of openings through the root portion of said fins disposed in a plane at one end of said drum substantially coincident with the end of said fuel nozzle.

4. In an oil burner, 'a draft tube providing a flow of air to a combustion chamber, a fuel pipe coaxially disposed within said draft tube and terminating in an atomizing nozzle, a turbulator for conditioning the air for mixing with the atomized fuel, said turbulator comprisinga drum coaxially disposed about said fuel pipe and within said draft tube to substantially enclose said atomizing nozzle, said drum comprising a cylindrical structure having a closed end on one side of the atomizing nozzle, said turbulator having openings in the circumference of said cylindrical structure for the admission of a first air stream from the draft tube to the interior of said cylindrical structure, exterior tangentially arranged finsbo'un'ding one edge of said openings for directing the first air stream along the inner surface of said cylindrical structure, an annular plate at the terminating end of the draft tube piloting one end of the cylindrical structure and spanning the annular space between the draft ube and turbulator, said turbulator having openings in said cylindrical structure disposed in the roots of said fins providing for admission of a second air stream from said draft tube to the interior of said cylindrical structure, the openings for admission'of said first and said second stream air being staggered for intermixing air in a zone coincident with emission of atomized fuel to produce an atmosphere of ignitible and combustible fuel in close proximity to the terminus of the draft tube. v

'5. The combination set forth in claim 4 wherein the annular plate piloting one end of the cylindrical structure is apertured and forms a pressure head for restricting lineal movement of air in the draft tube and for assisting in radial movement of air through said openings in the roots of said fins.

6. In an oil burner having a draft tube and an 'oil atomizing nozzle for effecting-"combustion of a liquid fuel, a turbulator disposed at the exit end "of the draft tube and encompassing said fuel "nozzle, an annular plate at the end of the draft tube supporting the concentrically arranged turbulator, said turbulator comprising a cylindrical cup-like drum having its open end piloted into the annular plate, and having a series of openings through the wall portion with tangentially arranged fins for admitting an air stream of cyclonic nature which moves forward within the drum and mixes with the cone of atomized fuel, said turbulator having a series of surface openings located in the roots of said fins admitting air flow along radial paths from the draft tube substantially at the plane of the fuel nozzle for reducing the noise of burner flame, and a defiector disposed over the open end of the turbulator for directing the air movement from both of said sets of openings into the path of the atomized fuel, said annular plate supporting the turbulator at the end of the draft tube and having a series of openings for lineal flow of air from the draft tube into the combustion chamber outside of the burner flame, and for restricting the lineal flow of air so that tangentially and radially moving air streams from the draft tube through the drum will be enforced.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,221,519 Jones et a1 Nov. 12, 1940 2,262,525 De Lancey Nov. 11, 1941 2,304,294 Wood Dec. 8, 1942 2,500,344 Carter Mar. 14, 1950 2,502,664 Nest Apr. 4, 1950 2,513,645 Hallinan July 4, 1950 2,516,063 Logan et a1 July 18, 1950