US2576053A

US2576053A - Furnace baffle construction and arrangement

Info

Publication number: US2576053A
Application number: US102518A
Authority: US
Inventors: James E J Toner
Original assignee: BETHLEHEM FOUNDRY AND MACHINE
Current assignee: BETHLEHEM FOUNDRY AND MACHINE; BETHLEHEM FOUNDRY AND MACHINE Co
Priority date: 1949-07-01
Filing date: 1949-07-01
Publication date: 1951-11-20
Anticipated expiration: 1968-11-20

Description

J. E, J. TONER 2,576,053

F'URNACE BAFFLE CONSTRUCTION AND ARRANGEMENT 2 SHEETS-SHEET 1 MCI., i.

Nov. 20, 1951 Filed July 1, 1949 Inventor Nov. 20, 1951 J. E. J. TONER 2,576,053

' FURNACE BAFFLE CONSTRUCTION AND ARRANGEMENT Filed July 1, 1949 2 sHEETs-SHEET 2 Inl/enfer Y JmeJE. Tone/1,

Patented Nov. 20, 1951 l UNITED STATES FURNACEBAFFLE CONSTRUCTION AND ARRAN GEMEN T James E. J. Toner, Bethlehem, Pa., assignor to Bethlehem Foundry and Machine Company, Bethlehem, Pa., a corporation of Pennsylvania Application July 1, 1949, Serial No. 102,518

18 Claims. l

This invention relates to new and useful improvements in furnaces, and more particularly to furnaces of the general type disclosed in U. S. atent No. 2,264,226 granted November 25', 1941.

lin this type of furnace, air is introduced tangentially into a tubular combustion chamber and the fuel is supplied to the chamber in an' axial direction. From the beginning, in domestic size furnaces of this type, the limitations in respect of thelength of the tubular combustion chambers for household installations wereY such that the combustion chambers could not be made long enough for complete combustion ofthe fuel to take place within the tubular chambers. The result of this was that not only was the furnace ineilcient` in operation but substantial' smoke was present causing carbonization not only on theK walls of the furnace and stack but also at the fuel nozzle to an extent that the latter became inoperative after short periods of use.

One solution to the difficulties presented appeared to be the necessity for intermixing the fuel and air in the tubular combustion chamber to an extent that would insure complete combustion of the fuel within the chamber. In the aforesaid patent this was sought to be accomplished by inserting in the tubular combustion chamber an annular bale member which, while preventing too rapid movement of the burning fuel toward the outlet end of the chamber, functioned primarily to cause a sudden or abrupt change in the flow of iiuid through the combustion chamber thus creating a turbulent condition at the bale that produced a satisfactory intermixing of the fuel and air for combustion. Later, additional baies were installed as requi-red.

The baffles of the aforesaid` patent furnished an adequate solution to the problem so long as the domestic fuel oils available consisted mainly of distillate oils. However, since the end of the war the use of catalyst cracked oils in domestic heating fuels has increased until at the present time the maior proportion of the oils in domestic fuel oils are produced by catalytic cracking processes. These so-called cat-crack oils have nen` found to have different combustion properties and characteristics than distillate oils with the result that the baille structure of the aforesaid patent did not provide the degree of fuel-air mixture required to effect complete combustion of such cat-crack oils within the relatively shcrt tubular combustion chambers of domestic .me furnaces.

With the foregoing in mind, the principal ob- 2 ject of the present invention is to provide for a furnace of the type described a novel baffle construction which is operable to effect an intermiXing of fuel and air to a degree causing cornplete combustion of the fuel to take place within the furnace combustion chamber.

Another object of the invention is to provide a novel baffle construction as set forth which s operable to cause a sudden and abrupt change in the flow of fluid through a tubular combustion chamber and to create a maximum degree of turbulence in the fluid at and through the baffle to thereby cause maximum intermxture of the fuel and air and insure complete combustion of the mixture within the chamber.

A further object of the invention is to provide in a furnace of the type set forth a novel arrangement of baffles embodying the aforesaid features and advantages.

These and other objects of the invention and the various features and details of the construction and operation thereof are hereinafter fully set forth and Ydescribed, with reference to the accompanying drawings, in which:

Figure 1 is a longitudinal sectional view vertically through a furnace embodying the present invention;

Fig. 2 is a view in perspective of a baffle member constructed according to the present invention, a portion thereof being broken away to better illustrate certain details of the construction;

3 is an enlarged elevational. vieW of the bailie from the outlet end thereof;

Fig. 4 is a sectional. view taken on line 4l, Fig. 3;

Fig. 5 is a fragmentary sectional View of the combustion chamber of a furnace showing a baffle arrangement different from that in Fig. l;`

Fig. 6 is a view similar to Fig. 2 of a modified form of baille;

Fig. '7 is an enlarged elevational View of the baille construction shown in lig. 6, from the outlet end thereof;

Fig. 8 is a sectional View on line Fig. 7; and

Figs. 9 and 10, respectively, are fragmentary sectional views showing other arrangements of baies which give satisfactory results.

Referring now to the drawing, the invention is shown conjunction with a domestic furnace of the type described comprising an open-ended tubular combustion chamber l and a surrounding series of open-ended fire tubes 2. Air is introduced tangentially into the combustion tube l4 by means of a blower t and the fuel to be burned is discharged coaxially into the chamber I by means of a suitable nozzle 1i having associated therewith the customary spark ignition 5.

The combustion gases leaving the outlet end of the tubular chamber I make a return pass through the re tubes 2 and are then discharged up the usual stack 6. The tubular combustion chamber i is lined with a plurality of refractory sleeves i interspersed with battles and 9 arranged, for example, as shown in Fig. l of the drawing. The baiile may be of the type and construction shown and described in the patent previously referred to herein.

The present invention is concerned primarily with the construction of the baffle 9 and the arrangement of one or more such baliles within the tubular combustion chamber I of the furnace. Referring now more particularly to Figs. 2, 3 and 4 of the drawing, the baiiie 9 is of a generally annular construction and preferably is fabricated of refractory material. The baffle has a generally tapered opening Ii) therethrough which diverges in the direction of passage of the air and fuel therethrough. As shown in the drawing, the opening il) through the baille 9 is of irregular configuration or shape and is provided with a plurality of recesses I I arranged in uniformly spaced relation about the baiiie opening i@ and the contour of the recesses II is such that there is formed'between adjacent recesses a rib portion I2 which projects inwardly of the baffle toward the center of the opening of the baffle, the ribs I2 being disposed alternately with said recesses around the baiiie opening IB. Y

As shown in Fig. 4 of the drawing, the surfaces of the recesses II and the surfaces of the ribs l2 both slope outwardly or diverge in the direction of fluid flow through the baiiie opening. Furthermore, as will be apparent from a reference to Fig. 3 of the drawing, the arrangement of the recesses II and ribs I2 as well as the angle of divergence of their respective surfaces is'such that the baffle opening li) is of correspondingly irregular contour Aat both the inlet and outlet sides ofthe bafe.

In a tubular combustion chamber, for example, such as shown in Fig. l of the drawing, the inlet end face I3 of the baiie S constitutes a barrier which effects a sudden change in the direction of ow of the air through the chamber and sets up a high degree of turbulence in the air resulting in a substantial initial mixture of the air and fuel which, by reason of the pressure of the continuously incoming air supplied to the combustion chamber, is caused to iiow in a generally spiral course through the opening i il in the baiile. As the partially mixed fuel and air thus moves in a spiral course through the opening of the baille 9, .the irregular surface which is provided by the alternately arranged recesses il and inwardly projecting or raised rib portions i2, creates a very high degree of turbulence in the Huid as it passes through the baiiie thereby causing substantially complete intermixing of the fuel and air and producing a highly combustible mixture which is completely burned during the remainder of its passage through the adjacent refractory sleeve 1, baiile 8 and subsequent sleeves 'i prior to reaching the outlet end of the tubular com bustion chamber. Another arrangement of a plurality of baffles 9 in association with sleeves 'I and a baffle 8 in a, tubular combustion chamber of longer length is shown in Fig. of the drawing. A modified form of the bafe is shown in Figs. 6, 7 and 8 of the drawing wherein there is illustrated a baffle member 9a, of generally annular construction, having a generally tapered opening Illa therethrough which diverges in the direction of passage of the air and fuel through the baiiie and is provided with a plurality of recesses Ha arranged in uniformly spaced relation about the baffle opening lila with respect to the alternately arranged ribs 62a that project inwardly of the baille toward the opening there- Y through.

As shown in the drawing, the surfaces of the recesses I Ia and the surfaces of the ribs I2a both slope outwardly or diverge in the direction of flow through the baille opening Ita and, in this particular embodiment of the bale construction, the angle of slope or divergence of the baifle surfaces surrounding the opening Illa is greater than the angle of slope of the corresponding surfaces of the baiiie construction previously described so that in the construction of Figs. 6, 7 and 8 the surfaces merge into a truly circular surface surrounding the baffle opening lila at the outlet side of the baflie. Thus, in the form of baiiie construction shown in Figs. 6, 7, and 8, the baffle opening Ida is of irregular contour at the inlet side only of the baiiie and is of truly circular contour orshape at the outlet side thereof. The operation of the several recesses ila and ribs i2a in the baiiie construction of Figs. 6, '7 and 8 to create a high degree of turbulence and intermixture of air and fuel during passage thereof through the baille opening lila is substantially the same as that set forth with respect to the baille construction shown in Figs. 2, 3 and 4.

Other arrangements of bafes which give satisfactory results are shown in Figs. 9 and 10 of the drawings, Fig. 9 showing a modified arrangement of the baiile assembly of Fig. 1 and Fig. 10 showing a modification of the baflie assembly of Fig. 5. In the case of Figs. 9 and 10 the baie arrangements are similar, respectively, toY those shown in Figs. 1 and 5 of the drawings except there has been added intermediate the first baiile 9 or 9a and the sleeve 'i or "la, as the case may be, a baiiie Iii or Ida, respectively, having a tapered internal opening of circular conguration with the larger end of said opening facing the inlet end of the combustion tube so that the smaller end of the opening is disposed contiguous to the inlet end of the opening Il) or lita in the irregularly contoured bailies 9 orV 9a, respectively. The use of a baffle I6 or lli-a constructed and arranged as described provides with the adjacent baiile of irregular contour a restriction in the combustion chambers which functions in the manner of a nozzle or venturi to provide increased turbulence and more complete intermixing of the air and fuel passing therethrough.

From the foregoing description it will be observed that the present invention provides a novel bafiie construction for furnaces of the type described which embodies novel features of construction and arrangement operable to effect a maximum intermixing of fuel and air to the degree required to effect complete combustion Vof so-called cat-crack oils within the tubular combustion chamber of the furnace. The invention also provides a novel baffle construction as set forth which in addition Vto effecting a sudden or abrupt change in the direction of flow through the combustion chamber operates effectively to create a high degree of turbulence in the fluid as the latter passes through the baffle thereby to effect optimum intermixture of the fuel and air and insure complete combustion thereof within ammessa 5;. the-limitsioifthei combustion; tube of, the; furnaces,l

While: certain embodimentsrotthe present ini--` vention have: been illustrated andfdeseribedrfhereein=, itisanotz-intended to; limittheinventiorr tosucn disclosures, and changes and-,imodificationsi may bei made:` therein and;theretofwitbinfthe scope` of; the; yfollowingl i. claims.

I claim:

1r.. As: an' article; otxmanufacture'.. a. baille' compris-ing: a generally annular` member having a, taperedfiinternali` opening; therethrough oifirregu lar :configuration defined; by,ialternately,` disposed recesses rand: ribszextending. axially of;the:member,1 andi arranged in, uniformly spaced; relation arounid` said opening. saidireoessea .being tapered intthef direction: oftap'erkv of the; opening. through. the? member andisaidfiribs being `tapered' in the` oppositef direction.

2; As:amarti'cle` of manufacture; a. baille comfprising:` ar generally.-` annular member having a; tapered; internal; opeuingfv therethrough of irregultu'iconilguration` defined byvalternately `disposed recesseseandribs extending.:axiallyofthe member andl arranged in.. uniformly spacedl` relation., around said opening; the. surfaces of saidrecessesf and' ribs sloping entirely throughY the bailieopening at a predetermined anglefto-causefsaid openingf to be of' correspondingirregular contour at both* endsV thereof.

3'. les` an .article oft manufacture, a. baille comprisingV a generally annular member having a: tapered'internalopening` therethrough of irregular conligurationr denedlby i alternatelyadisposed i roundedrecesses, and inwardly projected" ribs` extending axially of"thehmemberI and arranged" inwuniformly spaced relation `aroundsaid openl ing, said recesses! beingtaperediin; the direction oftaper of the :opening through` they member and said` ribs. b'eingftaperedfin. the: opposite directions.

4.' As.- an: article-ofrnanui'acture, a bailleconfi-v prising a generally annular member havingv a tapered internal? opening therethrough of irregulariconn'guration delnedby alternately disposed? :recesses-.andfribs.` extending axially `of the member@V and: arranged-1" in uniformly spaced relation, aroundisaid; opening, .thesurfaces ot'V said. recesses. andfribssrsloping .entirelyy through: `the baille openingvatza predetermined` angl'eto,` causesaid openingtoV` be; of correspondingly irregularv contour at bothi ends thereof; sai'derecesses being taperedin4` the direction .ot tapersof; the opening through,` the: member'. and@ said z ribs beingV tapereda` the op posite direction..

5. Asv anar-ticle o-f;.man11f acture,. a baille com,- p risingf` a generally annular;V member having a taperedf-` internal" opening therethrough of ir-`` regular; configuration, donned: byr alternately dis.- posed recessesrand` ribs` arranged in uniformly' spaced relation around said opening, the surfaces; ofsaidrecessea and ribs sloping, -im-one direction through the-i baille at: a `predetermined;` angle to4 cause saidsurfaces-r, to merge. intona, circular sure face adjacentone endet theopening anclfthereby` provide a; batiefopeningfof, reglulancontourrat, said. one,endthe other end of; the baliieopening, hav ing an` .irregular contour.

6. As,l an article. ot manufacture, a-bailiecomf-V prising a: generally annular member having a1 tapered internalr opening therethrough-of irreg` ular coniiguration donned by alternately disposed: rounded recesses and` inwardly projected ribs arranged,inuniormly spaced relation aroundsa-id` opening, `the surfaces off said recesses and ribs'V sloping intona direction through the: baille `at `a predetermined-I angle te* cause` saidsurfaces: to-

mergeinto a. circular surface adjacent one-endu of thefopeningf and thereby provide a,bailleopelby ing ofV- regularcontourat said one end; the-other end of; the baille opening having an` irregular contour.

'7. In a furnacecomprising a. cylindrical" com-H bustionr tube to theinletvend of. which air is supplied; tangentially and fluid fueluis introduced` axially thereof, at least one: baule nsaid tube inwardly adjacent the inletend of the tube hav.- inga tapered internal opening of irregular con-- iiguratiow constituted of alternately arranged recesses and ribs with the smaller end of said4 opening disposed adjacent said inlet end of. the, tube, atleast one: sleeve 'sectionrlining the tube,

atv the other end of said baille, and another baille inA thetubefat the other side ot said. sleevefrom,

the first mentionedA baille and having :a tapered internal opening of circular configuration with` the smaller end thereofl disposed adjacent said sleeve.

8.- n a furnace comprising a cylindrical com-- bustion tube to the inlet end of which air is supplied tangentially and fluid iuelis introduced` ,axially thereof, at least one baille in said. tube inwardly adjaeentthelinlet end of the tube having a tapered internal openingr of irregular configuration constituted of alternately arranged` ;there of, a sleeve-sectionliningthe tube at the other end-oi` said baille, and another baille in the tube at the other sideof said sleeve from the rst mentioned baille andihaving a `tapered,

internal openingof circular configuration with the smaller end thereof` disposed adjacent said sleeve.

9i; In a` furnace comprising a cylindrical combustion tube to.- the inlet end of which air is` supplied tangentiallyand fluid fuel isY introduced axially thereot,` at least' oney baille i-n said tube inwardly adjacent` the tube. inlet` endhaving a tapered internal openingof irregular conguration constituted` of'a-lternately arranged recesses and ribs with; the smaller end of said openingdisposedzadjacent the inletendof the' tube, the surfaces of said recesses and ribsl sloping throught the bailleat` a predetermined angle to cause said surfacesy tomerge into-a circularsura face adjacent the larger end` of `thev opening and thereby provide a baille opening` of'` regular oontour at said larger ende with the smaller end of the baille opening having an irregular contour, and another baille .in the tube spacedulon-` gitudinally. thereof fromithe rst baille and havting; a.. tapered, inter-nal openingot circular con-- figuration with the smaller end thereof dis-I posed adjacent said ilrst baille.

10. In` a. furnace comprising. acylindrical combustion tube tothe inlet end. of which air is` sup,m

plied tangentially and uidfuel: is introduced.

axially thereof, a `sleeve section lining the inlet end-portionof the combustion tube, a` pair oi bailles in juxtapositionvin said tube inwardly adjacent .the sleeve section eachfher/ingA a; tapered internal openingl of irreefuleu' configuration- 1 con` stituted` of alternately arranged recessesand ribs, with the: smaller end' ofthe opening: dise posed adjacent the inlet end of: tlietube; a plu.- rality` oiA sleeve` sections lining the tube at.` the otherf of saidrpair oixbaiiles, lanother baille in the tube adjacent said plurality of 'sleeves' having a tapered internal opening of circular configuration with the smaller end thereof facing the inlet end of the tube, and a plurality of additional sleeve sections lining said tube at the other end of said other baiile.

1l. In a furnace comprising a cylindrical combustion tube to the inlet end of which air is supplied tangentially and fluid fuel is introduced axially thereof, a pair of baffles in said tube inwardly adjacent the inlet end thereof each having a tapered internal opening of irregular configuration constituted of alternately arranged recesses and ribs with the smaller end of the opening disposed adjacent the inlet end of the tube, the surfaces of said recesses and ribsV sloping entirely through the bale at a predetermined angle to cause the opening to be of correspondingly irregular contour at both ends thereof, a plurality of sleeve sections lining the tube at the other end of said pair of baffles, and another baie in the tube adjacent said sleeves and having a tapered internal opening of circular conguration with the smaller end thereof facing said pair of baflies.

12. In a furnace comprising a cylindrical combustion tube to the inlet end of which air is supplied tangentially and fluid fuel is introduced axially'thereof, a sleeve section lining the inlet end portion of the combustion tube, a pair of baliies in said tube inwardly adjacent the sleeve section each having a tapered internal opening of irregular configuration constituted of alternately arranged recesses and ribs with the smaller end of the opening disposed adjacent the inlet end of the tube, the surfaces of said recesses and ribs sloping through the baiile at a predetermined angle to cause said surfaces to merge into a circular surface adjacent the larger end of the opening and thereby provide a baiiie opening of regular contour at said larger end with the smaller end of the baffle opening having an irregular contour, a plurality of sleeve sections lining the tube at the other end of said pair of baffles, another baiile in the tube adjacent the last-mentioned sleeves having a tapered internal opening of circular configuration With the smaller end thereof facing the inlet end of the tube, and a plurality of additional sleeve sections lining said tube at the other end of said other baille.

13. In a furnace comprising a cylindrical combustion tube to the inlet end of which air is supplied tangentially and fluid fuel is introduced axially thereof, a sleeve section lining the inlet end portion of the combustion tube, a first baflie in the tube adjacent the sleeve and having a tapered internal opening of circular configuration with the larger end thereof adjacent said sleeve, and a second baifle in said tube inwardly adjacent the first baffle and having a tapered internal opening of irregular conguration constituted of alternately arranged recesses and ribs with the smaller end of said opening disposed adjacent said first baiile.

14. In a furnace comprising a cylindrical combustion tube to the inlet end of which air is supplied tangentially and fluid fuel is introduced axially thereof, a sleeve section lining the inlet end portion of the combustion tube, a first baffle in the tube adjacent the sleeve and having a tapered internal opening of circular configuration with the larger end thereof adjacent said sleeve, a second baffle in said tube inwardly adjacent the rst baffle and having a tapered internal opening of irregular configuration con? stituted of alternately arranged recesses and ribs with' the smaller end of said opening disposed adjacent said rst baie, the surfaces of said recesses and ribs sloping through the baflie 'at a predetermined angle to cause the opening to be of correspondingly irregular contour at both ends thereof.

15. In a furnace comprising a cylindrical combustion tube to the inlet end of which air is sup plied tangentially and fluid fuel is introduced axially thereof, a sleeve section lining the inlet end portion of the combustion tube, a first bailleV in the tube adjacent the sleeve and having a tapered internal opening of circular conguration with the larger end thereof adjacent said sleeve, a second baie in'said tube inwardly adjacent the first baille and having a 'tapered internal opening of irregular configuration constituted of alternately arranged recesses and ribs with the smaller end of said opening disposed adjacent said first bale, a sleeve lining the tube at the other end of said second baffle, and another b ailie in the tube adjacent the last-mentioned sleeve having a tapered internal opening of circular configuration with the smaller end thereof disposed adjacent said sleeve.

16. In a furnace comprising a cylindrical com-` bustion tube to the inlet end of which air is supplied tangentially and iiuid fuel is introduced axially thereof, a sleeve section lining the inlet end portion of the combustion tube, a first baffle in the tube adjacent the sleeve and having a tapered internal opening of circular configuration with the larger end thereof adjacent said sleeve, and a pair of baffles in said tube inwardly adjacent the first baiile each having a tapered internal opening of irregular configuration constituted of alternately arranged recesses and ribs with the smaller end of said opening disposed adjacent said first baiile.

17. In a furnace comprising a cylindrical cornbustion tube to the inlet'end of which air is supplied tangentially and iiuid fuel is introducedY axially thereof, a sleeve section lining the inlet end portion of the combustion tube, a first bale in the tube adjacent the sleeve and having a tapered internal opening of circular configuration with the larger end thereof adjacent said sleeve, and apair of baffles in said tube inwardly adjacent the first baffle each having a tapered internal opening of irregular configuration constituted of alternately arranged recesses and ribs with the smaller end of said opening disposed adjacent first bafe, the surfaces of said recesses and ribs sloping through the baliie at a predetermined angle to cause the opening to be of cor` respondingly irregular contour at both ends thereof.

18. In a furnace comprising a cylindrical combustion tube to the inlet end of whichair is supplied tangentially and fluid fuel isV introduced axially thereof, a sleeve section lining the inlet end portion of the combustion tube, a first bailie in the tube adjacent the sleeve and having a tapered internal opening of circular configuration with the larger end thereof adjacent said sleeve, and a pair of baffles in said tube inwardly adjacent the first baiiie each having a tapered internal opening of irregular configuration consttuted of alternately arranged recesses and ribs with the smaller end of said opening disposed adjacent said first baffle, the surfaces of said recesses and ribs sloping through the baiile at a predetermined angle to cause the opening to be 9 of correspondingly irregular contour at both ends thereof, sleeve sections lining the tube at the other end of said pair of baies, and another bafe in the tube adjacent the last-mentioned sleeves and having a tapered internal opening of circular configuration With the smaller end thereof disposed adjacent said sleeves.

JAMES E. J. TONER.

REFERENCES CITED Thefollowing references are of record in the file of this patent:

Number Number 10 68,354 235,321

10 UNITED STATES PATENTS Name Date Hague Oct. 4, 1887 Whitney Nov. 14, 1893 Smallwood Dec. 30, 1913 Toner Nov. 25, 1941 FOREIGN PATENTS Country Date Germany May 3, 1893 Germany May 31, 1910 Germany Apr. 10, 1923