US1820755A - Method of preparing liquid fuel for burning - Google Patents

Description

Aug. 25, 1931. J. l. MCMULLEN '1,820,755

I METHOD OF PREPARNG LIQUID FUEL FOR BURNING Filed March 9, 1929 dttozmql Patented Aug. 25, 1931-V UNITED STATES JOSEPH I. MCMULLEN, orV BETHESDA, MARYLAND METHOD OF PBEPARING LIQUID FUEL FOR BURNING Application mea Maren 9, 1929. serial No. 345,825.

(GRANTED UNDER THE ACT F MARCH 3, 1883, AS AMENDED APRIL 30, 1928; 370 0. G. 757) This application is filed under the provisions of the act of Mar.'3, 1883, c. 143, U. S. Statutes XXII, p. 625, as amended by act of Apr. 30, 1928. The inventiony described herein may be manfactured and used by or for the Government .for Government purposes, Without the payment to me of any royalty thereon.

This invention relates to liquid fuel burners and has for its `general object an improved method for securing complete combustion of andmaxi-mum heating efficiency from the fuel. l

Another object of this invention is to prjovide a liquid fuel burner having facilities for centrifugally raising. vfuel from a reservoir and discharging it; atomized and suitably mixed With air, into a combustion chamber in the form of a whirling frusto-conical shell. l

Anot er object of this invention is to provide a fuel burner in which the fuel is atom-l y ized as'it travels'from the reservoir to the discharge orifice andatthe same ,time subjected to the action of air and steam, the mixture being expanded in the course of its travel from the source of supply to the discharge.

Another object of this invention is to provide aburner in which the fuel is centrifugally 4rasied from the reservoir to the zdis charge orifice, and is subjected at approxi.

mately the initial point of its travel to the combined action of air and steam' so that before being discharged into the combustion chamber alsufiicient time interval will have elapsed to permit interaction between the oil, steam and air to secure a completely combustible mixture. l

Other objects of this invention are to prod uce a burner which is economical in fuel consumption, readily removable from the furnace to facilitate repairs, simple in construction and inexpensive to manufacture, and one which owing to the manner of discharging the fuel into the combustion chamber affprds a concentrated heating effect.

In order to make my invention more clearly understood, I have shown in the accom- 50 panying drawings means for carrying the same into practical effect, without limiting the improvements in their useful applica- 'tions to the particular constructions, which nular discharge orifice, while the lower end 5 of the mixing chamber is formed with a fuel. reservoir in communication with a suitable source of supply., an inverted frusto-conicalshaped atomizing head rotatablyA mounted in the mixing chamber, the upper lend of the head being disposed immediately beneath the spreader, the lower end projecting into the ,fuel in the reservoir, a series of spirally arrangedI divergently associated atomizing blades carried by the head, the -depth of the blades decreasing gradually from the upper to the vlower end of the head, an annular series of chambers communicating with the mixing chamber ata point adjacent the fuel reservoir and means for introducing and intermingling air and steam within the chambers.

In the drawings forming a part of this specification: v n

Figure 1 is a view partly 1n elevation and partly in section of an apparatus capable of carrying out my invention.

Figure 2 is a top view taken on line 2-2 of Figure 1.

Figure 3 is a fragmentary sectional vlew of the rotor showing the mounting of the fins. In the prevailing types of fuel burners especially those mixing oil and steam, one of the principal defects resides in the failure on the part of the designers to allow a sufiicient l time intervalto elapse after the steam, oil and.` air have been 1nterm1nglcd to secure a completely combustible mixture, and 1t 1s therefore the aim and purpose of this invention to avoid this defect by providing an apparatus wherein as the oil starts toward the discharge orifice, it is treated with air and steam which mixture is thoroughly inter-` ICO min led prior to its discharge into the combustion chamber.

Referring more particularly by numerals vto the drawings in which the same elements are designated by like symbols of reference throughout and 'especially to Figure 1, the apparatus comprises .a base, preferably cast in a single piece of some suitable metal, so as t0 form a single composite structure.

The base is provided with a circular bottom flange 1, adapted to rest on a support such as the floor of the furnace, althoug it is apparent that it may be of any other desired configuration, havlng formed integrally therewith, upwardly extending inwardly sloping walls 2. The walls 2 are provided with a series of apertures 3 designed to admit air to a circular casing 4, forming an up-' projecting extension ofthe sloping walls 8 of increased diameter extending upwardly from the top of the casing and terminatingI in an outwardly extendmg Bange 9. The recess formed by the walls 8 is intended toaccommodate an air induction mechanism mounted on a drive shaft 11 projecting from the motor. The air induction mechanism consists of a fan having angularly disposed blades 12 intended to draw air upward throu h` the a rtures 3 and 4thus among other 'o jects whlch willsubsequentl be more fully understood, provide for coo `ingthe motor.

A mixing chamber,.preferably cast in a single' piece and of the same material -as the base, is mounted on the frame above the motor. The ymixing chamber comprises a fiat circular base 13 mounted on the flange 9 of the frame and held in place by bolts 14.

The base 13 is formed 'with' a central depressed portion 15 forming a well, which portion is provided in addition with a recess 16 having a central a erture containing a packing (gland `17 in tie bottom,.through which the rive shaft 11 extends. r

A ball race 18 is mounted'on that portion of the shaft within the recess formed by the wall 16, and a ball race 19 is positioned therein, adapted to form a bearing by providing ball bearin s 21 operatingin the same. In addition a eeper 22 is fixed in the top of the recess flush with the bottom of the depressed portion 15 and held therein by a screw 23.

l An upper casing is formed with walls 24 extending upwardly from the base 13, having angular extensions 25 projecting inwardly and joined with outwardly projecting sides 26 forming a truncated conlcal recess with the tapered walls 15 of the central depression in the base. The side 26 is provided at its top with an annular shoulder 27, adapted to support rebrick 28 or other material forming the bottom of the combustion chamber of the furnace with whichthe apparatus is associated. y I

An atomizing head in the nature of a rotor 29 having tapered blades 31 positioned spirally on the outer face, is mounted on that portion of the shaft extending into the mixing chamber and fixed thereon by a spline 32 or held in any other suitable manner. vThe rotor 29 is preferably cast in the form'of a truncated conical body of some light metal with the blades integral therewith and it may be hollow in form as shown in Figure 2, including an extension 32, to lend to the lightness thereof.

The rotor 29 acts as a mixingl member. for' the material introduced into the chamber formed b the to casing and is rotated at a very rapid rate veing 'carried on the drive shaft of the motor. The shaft 11 extends above the top of the rotor and a dish shaped spreader 33 is mounted on the end, the top thereof bein iush with the .bottom of the combustion c amber in the furnace, and the sides tapered.

It will be noticed that the portionv 26 of the side 26 adjacent the sides of the spreader, is sloped outwardly from the major portion of the side 26 and corresponds in configuration with the tapered sides 33 of the spreader sothat the material thrown out by the revolving rotor will be sprayed out in the form of a truncated conical shell.

The exterior surface of the atomizing head and the confronting surface of the mixing chamber difer in slope to compensate for the configuration of the 'atomizing blades (31) whic graduallyl decrease in depth from the upper to the lower end of the head, the construction of the blades in conjunction with the adjacent surface of the mixing chamber formin' channels gradually increasing in depthA rom the lower to the upper endof the atomizing head to permit expansion of the mixture of steam, air and oil as it travels from the fuel reservoir to the discharge orifice.

Oil is introduced into the mixing chamber through a line 34 having an inlet in the .bot-

tom of the depressed portion 15 formed in they bast 13, so that the stream will act to produce a body of oil in the well formed by the depression 15.

The base is provided with a series of apertures 35 communicating with the apertures 3 in the bottom of the frame so that air drawn up through the motor by rotation of the fan blades 12 will force the same into the mixing chamber through the several apertures. `A series of nipples 36 havin their free end inclined as at 36 are fitted into the apertures. By reason of the inclined 'ends with the highest portion faced toward therotor, any material splashed will not fall through the apertures. A f In this connection it is to be noted the supply of fuel to the oil reservoir is suitably regulated so that the fuel therein will not exceed a level which would interfere with the return to the reservoir of oil discharged into the chambers (47') communicating with the lower end of the atomizing head.

The base 13 is provided in addition with an aperture 37 'adapted to receive a nipple (38)l having its upper end (38')7 inclined in a similar manner to the nipples 36 and for the same purpose.A The nipple 38 is connected with a suitable source of steam. There is shown an apparatus. consisting of a plurality of check valves 41 and 42 and a casing 43 forming an enlarged chamber, interposed in the line, said chamber having therein electrodes (44). l

The electrodes'44 are in electric connection with a cable 46 containing a plurality of conductors, which enter the lower part of the chamber. When water underthe usual pressure is introduced into the line, it passes through the valve 41 and the casing 43 and in contact with the electrodes, the temperature is immediately raised, and it is converted into steam almost instantaneously, and by reason of the pressure exerted it passes through the valve 42 through a pipe 39 and out the nipple 38 into the mixing chamber.. It is apparent that if too high a pressure is generated in the casing the valve 41 will be automatically closed and the pressure relieved by the steam passing through the valve 42 until the pressure is sufficiently lowered to allow opening of the valve 4l by the water head.

The operation of the apparatus will be readily undetstood. Oil is introduced through the line 34 and allowed to collect as a body in the well formed in the bottom of the mixing chamber where it is drawn olf by the rotating [blades of the rotor into the enlarged mixing chamber formed by the walls 24, where now in'atomized form it is mixed with steam comin through the line 38 and air, forced throng the apertures 35 by action of the fan blades 12. These materials are further atomizedand commingled while being conducted along the body of the rotor, which, having an extended Contact surface,

imparts a shapeto the material so that when 4it is discharged past the tapered edges of the spreader 33, it assumes the 'form of a truncated conical shell which has a large surface area for-burning.

` The enlarged portion' of the mixing chamber adjacent the lower end of the atomizing head is sub-divided by partitions (47) into an annular series of compartments (47 The space between th'e'rotor and the side 26 also serves as an additional mixing chamber as well as to impart the desired form to the fuel.

It has been found that certain qualities are jecting the atomized oil to the combined action of steam and air at approximately the starting point of its travel from the reservoir to the discharge orifice and further disintegrating and at the same time expanding the mixture to the discharge, secure complete fuel combustion and thus eliminates all soot accumulation. 4

While I have shown and described the preferred embodiment of my invention, I wish it to be understood that I do not confine myself to the precise details herein set forth, as it is apparent that many change and variations may be lmade therein, by those skilled in the art, without departing from the spirit of the invention, or exceeding the scope of the appended claims.

I claim:

1. A method of burning li uid fuel comprising, collecting a body of uel and maintaining a constant level thereof, drawing fuel from the surface thereof, mixing the fuel with steam and air, said air beingI supplied under forced draft, drawing the combustiblel mixture upwardly in the form of a rotating inverted truncated cone, and ejecting the fuel for burning.

2. A method of burning li uid fuel comprising, collecting a body of uel and maintaining aconstant level thereof, drawing fuel from the surface thereof into a mixing cham- -ber for atomizing same, mixing the-fuel with steam and air, said air being supplied under forced draft upwardly, drawing .the 'com bustible mixture upwardly in the form of a rotating inverted truncated cone and further atomizing same, and ejecting Vthe fuel for burning.

3. A method of burning liquid fuel" comprising, collecting a bodv of fuel, and maintaining a constant level thereof, drawing fuel from the surface thereof into a mixing chamber for atomizing same, mixing the fuel with steam and air, said air being supplied under forced draft upwardly, drawing the combustible mixture upwardly in the form of a rotating inverted truncated cone and further atomizing same, and ejecting the fuel for. burning to present a horizontal ring ignltlon surface.

4. A method of burning li uid fuel comprising, collecting a body of ucl and mamtaining a constant level thereof, drawing fuel from the surfgce thereof into a mixing chamber for atomizing same, mixing the fuel with steam and air, said air being supplied under 5 forced draft upwardly, drawing the com,-

bustible mixture upwardly in the form of a rotating inverted truncated cone and discharging the mixture in the form of a, thin angular ring, for further atomizing the mix- 1o tu-re and ejecting the fuel for burning to present a horizontal ring ignition surface.

In testimony whereof I affix my signature.

` JOSEPH I. MCMULLEN.

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