US2663170A

US2663170A - Heat exchanger

Info

Publication number: US2663170A
Application number: US189441A
Authority: US
Inventors: Gloyer Walter
Original assignee: American Locomotive Co
Current assignee: American Locomotive Co
Priority date: 1945-05-10
Filing date: 1950-10-10
Publication date: 1953-12-22
Anticipated expiration: 1970-12-22

Description

Dec. 22, 1953 w. GLOYER HEAT EXCHANGER Original Filed May 10, v.1945

4 Sheets-Sheet l UUUU INVENTOR WALTEQ GA OVER ATTORN EY W. G LOY E R HEAT EXCHANGER Dec. 22, 1953 4 Sheets-Sheet 2 Original Filed May 10, 1945 2/ 2 FIGS.-

44 3/ 32 as 34 35 36 7 as 59 40 4! INVENTOR WALTER G4 OYEP BY M d. ATTORNEY Dec. 22, 1953 w. GLOYER 2,663,170

HEAT EXCHANGER Original Filed May 10, 1945 4 Sheets-Sheet 4 G Fl H Wq/fer G/oyer.

IN VEN TOR.

ATTORNEY Patented Dec. 22, 1953 HEAT EXCHANGER Walter. Gloyer, La Grange, IlL, assignor;to-.;Amer- .ican, Locomotive Company, New .York,;:N. Y ma corporationcof'NewYork Original application May 10, 1945, 'SeriaLNo.

592,949. Divided and this applicationioctober I 10, 1950; Serial No. 189,441

4 Claims. (01. 62-1755) ill vThis inventionrelates to-a method of heat exchange.

This application is a divisional application, the parent application, now Patent Number this application. Figure 1.is aforeshortened front elevation of a heat exchanger constructed in accordance with this invention; Fig.2 is a plan view of the heat'exchanger; .Fig. 3 is a foreshortened side view of the heat exchanger, taken from the right side of Fig. 1,.partly in side elevation and partly in section on the.line.III+-III of Fig. 4, partsbeingbroken. away; Fig. 4 ,is a section. on theline-Iv lv ofFig. 3'; Fig. 5 is an enlarged sectional view Lonthe line -VV-:, of Fig.

3vof a. portion-of the. exchanger; Fig.6.;i5ran enlargedplanview. of one plate. of. the exchanger;

"Fig. 7. is anenlargedplan view rot-another; plate of the exchanger, adapted .torbe disposedadjacent the u plateof Fig. "6; Fig. 8.; is anenlarged plan view of .an; outer plate of .the :exchanger; adapted to be disposed adjacent-titheplateaof Fig. 7 and Fig. 9 is a foreshortened-view looking at the 1three .plates .of cli igs. 16-8 fromn-the left side thereof, parts being broken away .to :showthe lower third of .the plate of Fig. ,6, the; middle third ofthe plate of .Fig. 7 and the upperthird of theplate of .Fig.;8; rEigUlOis a:diag-rammatic plan .view of .'.the vapparatus on;-;a irBId Q d :scale showing an assemblage of heat exchangers and pipes connecting the .zheat exchangers, and Eig. 11 is a schematic layout illustrating reversalof some of thestreams for. the defrosting Operation.

The I heat exchange apparatus shown in Fig.

2,529,013, having been filed on-May '10, 1945 by 5 10 includes ninety heat exchangers I. These applicant, asthe sole inventor. exchangers are. identical andonly onewillbe-ide- The principal object of this invention is to scribed. provide'an improved-method of heat exchange. Theheatexchanger his of the;platetypehav- More particularly, it is theobject-ofthe invening pin fins. .Itincludesa topheader 2 :and;-:a tion to cool air by passing confined streams of 10 bottom header ;3,.the headers-being similarrand atmospheric air individually along individual being bolted respectively to top :and bottom passin confined streams of cold nitrogen, .no flanges-4of a-shel115- two of the air streams being adjacent to each Eachheader includes ,atsemi-cylindrical:dome other and-no two of the nitrogen streams being spartitionedintoza central-chamber lrandsside adjacent to each other. Theair and. nitrogen 15 chambers 8 311C119 on opposite sides thereof. streams are there after transferred or transposed Chamber 7 is provided with a small cylindrical so that the air streams flow through the confines nozzle [0 and chambers 28 andzflare providedrrepreviously containing the nitrogen and the spectivelywithjlarge cylindrical nozzlesdd rand nitrogen streams'flow through the confines Dre- 0 l2. The chambers are-closed attheirrinnerends vlously containingthe air streams so that deby a'wal1'l-3 in which are portsflateritobezdefrosting. is achieved whilethe transferred air is scribed for-communicating withtheshell. cooled. Another object is to coolgair by pass- The shell-5 is rectangular'in cross: section and in-g confined streams of air along :confined includes two walls 14 and i5 .each'formed .off a streams of nitrogen and confined streams of 25 long solid plategof metal. Wal1 |4awil1:be;c0noxygen, the latter two streams being arranged sidered theshell front wall for :the'purposeof to function in a novel and effective manner. clarity in the following description. The wide Other and further objects of thisinventionwill walls I6 of the. shellzare-built-upwelded construcappear from the following description, .theactions as will presently appear, these-walls :lli companying drawings andthe appended claims. I being weldedtothewalls l='4:andcl-5. The shell Referring to the drawings forming a part of 30 is very long (high) relativeato its crossesectional dimensions and is-bracedtexternallysby rowss-of spaced T-irons l1 extending across "the Walls 1 4 and I5,'and securedatogether .bytieboltszlB extending across the :walls l 6.

The shell is partitionedinto twelve=longitudinal compartments'or chambers :l'9-30 inclusive by eleven longitudinal plates '3l-4l inclusive provided with pinffins. wThe chambers are numberedin order from therfront :of'the :shel1--rearward and the-plates :are:similarlymumbered in order, 1platex3l .:being :adjacent chamber I 9 (Fig. 5) Plates :3 I :and: 24 l arersimilar but oppositely disposed. :Plates 3! and 4| eachhave rowso'f conical pin finst42,;arranged'insquare pitch, integral with its inner side, and cylindrical pin fi-ns 43. in line WithgthBTfihSflZOll itszouter-side. The pin fins are spaced and they extend substantially the full depth "of the chamber 1 in which they are disposedythe depth being thedistance, for example, between a'djacent plates.

Plates .;3 2, 53.4, :36, 53.8 rand x are-similar. Each has :conical "pin fins 4.4 :extending in alignment from its vopposite;sides. These; fins aresimilar'to fins 42. Plates rand 40 are :disposed so that their fins 44 on the outer sides fit in the spaces between the adjacent fins 42.

Plates

33, 35, 31 and 39 are similar. Each has conical pin fins 55 extending in alignment from its opposite sides. These fins are similar to fins 44 and are disposed in the spaces between these fins M. The clearance in the inner chambers between the pin fins is very small, but is shown enlarged somewhat in the drawings for clarity. The clearance between the cylindrical pin fins 43 is also shown enlarged in the drawings for clarity. The fins greatly reduce the net free flow area of the chambers.

Each plate also has extending from its opposite sides, rows of cylindrical bosses 46. The bosses extending outwardly from the plates 3| and 4| abut the walls 14 and I5, respectively and the other bosses extend half the depth of the adjacent chambers and abut each other, thus forming segmental bracing rods extending between walls l4 and [5 for bracing the plates against bending due to pressure differentials.

Each plate has integral therewith at its longitudinal edges, flanges 41. These flanges, when welded together, form th side walls l6, as is clearly shown in Fig. 5. The shapes of the flanges in cross section are best shown in Figs. 7 and 8. The flanges of all the inner plates are similar to the flange of Fig. '7, extending equal distances on opposite sides of the plate and having welding shoulders :8 formed in the outer longitudinal edges. The flanges of the outer plates are similar except that on the outer sides of these plates they extend beyond the cylindrical fins in order to abut the walls 14 and I5, which-are also provided with welding shoulders 48. Mating shoulders 48 form outwardly opening U-grooves for welding.

Nozzle ll communicates, through chamber 8,

with chambers l9, 2|, 24, 26 and 29, wall l3 being provided with ports 49 opening into these chambers at the right side (Fig. 1) thereof. Nozzle l2 communicates, through chamber 9, with

chambers

20, 23, 25, 28 and 30, wall l3 being provided with ports 5!] opening into these chambers at the left side (Fig. 1) thereof. Nozzle l communicates, through chamber 1, with

chambers

22 and 21, wall 13 being provided with ports opening into these chambers at the center thereof. While 7

ports

49 and 50 open into their respective chambers only at one end thereof, the fluid enterin the chambers through these ports will disperse through the spaces between the pin fins and entirely fill these chambers. The same is true of the center ports 5|, the dispersion here being in opposite directions on each side of the ports 5|.

Referring to Fig. 10, wherein an apparatus is shown including ninet heat exchangers in plan of the above described type, it will be seen that these exchangers are arranged in two groups of forty-five exchangers each. Each group is divided into two sets, one set including the nine exchangers A at the left in Fig. 10, and the other set including the remaining 36 exchangers B. The group at the bottom of Fig. 10 will be referred to as the front group and the other group as the rear group.

These exchangers are connected by piping as follows:

A set of four

pipes

52, 53, 54 and extends along both the front and back of the apparatus at the bottoms of the exchangers thereof. Pipes 52 are connected to the adjacent bottom nozzles l2. Pipes 53 are connected to the adjacent bottom nozzles I Pipes 54 are connected to the adjacent bottom nozzles ID of exchangers B. Pipes 65, which are shorter than the other pipes, are connected to the adjacent bottom nozzles 59 of exchangers A.

A set of four

pipes

56, 51, 56 and 53, serving both groups, extends along the apparatus between the two groups thereof at the top of the exchangers. Pipe 56 is connected to the adjacent top nozzles l2. Pipe 51 is connected to the adjacent top nozzles ll. Pipe 58 is connected to the adjacent top nozzles W of exchangers A. Pipe 59 is connected to the adjacent top nozzles l6 oi the exchangers B.

The above described connections between the nozzles and their respective pipes are through branch pipes as shown diagrammatically.

The apparatus is laid out in a rectangle in longitudinal rows of fifteen exchangers each and transverse rows of six exchangers each. Thus each group includes fifteen transverse rows of three exchangers. The three exchangers of each transverse row are connected in series, the top nozzles of the outer fifteen exchangers being connected to corresponding top nozzles of the adjacent exchangers, these last exchangers having their bottom nozzles connected to corresponding bottom nozzles of the inner adjacent exchangers. The transverse rows of three exchangers of each group are connected in parallel with the

adjacent pipes

52 and 53, and with

pipes

56 and 51, the rows of exchangers B thereof are connected in parallel with the adjacent pipe 54 and with pipe 59, and the rows of exchangers A thereof are connected in parallel with the adjacent pipe 55 and with pipe 56. Itwill be obvious that the apparatus could include a greater or lesser number of exchangers, if desired, and the sets A and B could be rearranged to have a different number of exchangers each.

The present invention proposes a method of cooling hot air. The operation of the aforedescribed heat exchanger and apparatus will be o set forth, by way of example, in connection with carrying out the above method.

Pipes

52 and 56 may be for air or nitrogen. As

. will later more fully appear, they are employed at times for each fluid in carrying out the present method. Assuming that, to start with, they are for nitrogen, then pipes 53 and 5! will be em ployed for air. The directions of flows are n dicated in Fig. 10 by arrows. As an example, air from the atmosphere is compressed to pounds per square inch pressure at degrees Fahrenheit, and is conveyed to the exchangers of the apparatus by the two pipes 53, flowing into the bottom nozzles H connected thereto and flowing in series through each transverse row of three exchangers, entering the pipe 51 from the top nozzles ll connected thereto.

According to the present invention, this hot air is cooled to 250 degrees Fahrenheit by cold nitrogen (-266 degrees Fahrenheit) and oxygen (-288 degrees Fahrenheit), both at 10 pounds per square inch pressure. The main stream of nitrogen is delivered to pipe 56 and conducted thereby to each of the nozzles 12 connected thereto for series flow through each transverse row of three exchangers, entering the pipes 52 from the bottom nozzles l2 connected thereto. The oxygen is delivered to pipe 59 and conducted thereby to each of the nozzles l0 connected there:

to for series flow through each corresponding transverse row of three exchangers B, entering the pipes 54 from the bottom nozzles ill of the exchangers B connected thereto. A fourth stream is delivered to pipe 58 and conducted as the air is cooled. Fora continuous-operation of the process, therair flowrchambers of the="exchanger have therefore to be defrosted "and cleared from time; 'to time. This is done 'by switching air and the maintni-trogen streams from-one to the other-of their-"respective flow chambers at: a definite switching: cycle. The eol'd main stream nitrogen, whilebeing heated "to'ninety' degrees Fahrenheit as aforesaid-in thechamberspreviously-containing air, willyaporize the solidified carbon dioxide and water present in the chambers through which it is flowing and will carry them out of-the exchangers.

For a. successful defrosting operation, :the mainstream of nitrogen hasto be of approximately thesame-temperature-as the air onthe hot side.

For thispurpose an 8 degreeFahrenheit approach for the main nitrogenstreamon 'the cold'end of the exchangerapparatus isdesired. As :mentioned before, the main nitrogen. stream has a temperature-of -266 degrees Fahrenheit when approaching the exchanger apparatus. This temperature has to be brought up to 258 degrees Fahrenheit to satisfy'the above-mentioned limitationand this is done by quenching into theentering meanstream of nitrogen, before its heat exchange with air, the aforementioned fourth so-called unbalanced-nitrogen.stream after this fourth stream has been in heat :exchange' with air. This fourth stream is relatively small and is heated from 266-degrees Fahrenheitto QO-degrees Fahrenheit as aforesaid, and thereafter quenched into the main nitrogenf stream in any suitable manner to bring the main nitrogen stream inlet temperature up to 258 degrees Fahrenheit. The main nitrogen stream then enters the :exch'ange'rs suitable for defrosting at 258 degrees Fahrenheit and is heated to 90 degrees Fahrenheit at leaving the exchangers. Thus-the fourth stream takesthe place of oxygen in the exchangers A and is:in-r-heat" exchange rer lation withthe air and further-.preheats th'emain nitrogen stream during defrosting. Of course both of the chambers in communication with the nozzles ll and with the nozzles 12 have to be alternately defrosted due to the switching of the air.

The schematic layout for the defrosting operation is illustrated in Fig. 11. For convenience, the exchangers A and B as shown in Fig. are shown as blocks in Fig. 11. The various piping and valves in addition to Fig. 10, necessary for defrosting are shown schematically.

Lines

52 and 53 and lines 56-58 are shown as they appear in the overall layout of Fig. 10.

The various valves 60 are always either all open or all closed. Similarly the valves 6! are either all open or all closed at the same time being opposite to valves 60. For the description given concerning Fig. 10 valves 60 are all open and valves Bl are all closed. Hot air enters lines 53, :passcs through :the exchangers and remerges coldithrough line 5-1. Coldnitrogen enters line 56 and emerges hot through lines 52. The -unbalance'dcoldmitrogen' stream enters line 58 and emerges "from lines v55. By following line on Fig. I11,"-With the valves :in the position stated, the unbalanced nitrogen stream from both sets of exchangers A is returned to the main nitrogen stream for quenchingat junction 62 after ithas' passed inheatrexchangerelation and before the main'nitrogenfstream passes in heat exchange relation as stated supra. Thus the apparatus operates in one direction. I

When it is necessary to defrost, the air and nitrogen streams must be reversed. That is, the .hot .airimust :now enter line Eli-where the cold.nitrogenhad previously entered andthe cold nitrogen must-enter line53 where'the hot-air had previously'entered. rIn addition, the unbalanced nitrogen istreammust'be quenched, after it has passedtin-iheat'exchange relation, into line53 into themaininitrogen stream before'it passes in heat exchange relation. This-is done'at junction'63.

All that is necessary 1 to accomplish these conditiOIIS iSIOIBVEISBTthB positions of all 'valves. In other words all valves are now closed and all valves-6| "are opened. By following the lines on Fig. 11 itcan'be'seen that the fiow is asrequired fordefrosting. The positionsxof valves 69 and 6| areperiodicallychanged as the apparatus requires defrosting.

' The. above mentioned defrosting" switching operation "of the air and imain nitrogen streams necessitates identical tchamber arrangement for air and main nitrogen streams. Size and an rangement are dictated "by the allowable -pressureidrop-on'the low pressure nitrogen side. This identical chamber arrangement is best shown in Fig. '5. -When nitrogen is admitted through pipe 56,

itfiowsthrough chambers

23,23, 25, 28 and BIL-but when-theswitch ismade so that nitrogen is admittedthroughzpipe'5?, then it flows through chambers 1:9, 2!, 24, S25 and 29. This effects an alternating of' fiow of-nitrogen and air but 'maintains the same-relation. That is,

' before the switch; thei'twelve chamber l9-301have the'fluids arranged inia definite order-and after the switchjitheisame order is 'f'oundbut in the opposite directiomthatis, from chamber 30 to it. The cold oxygen is always in heat exchange relationxwithastream of air.

This-invention is adapted-to be employed'intheiproduction of pure oxygen "from atmospheric air, which :is "compressed and then cooled in the apparatus 'of' the:'preseiit invention. oftheilow temperature-of the oxygen when producedyit maybeutilized in the apparatus as a supply ofan air cooling mediumthereby effecting an economy. "In the present'method of'cooling air by nitrogen, oxygen, for the reasons above stated, is preferably also employed, but may not be availed of in all instances. When the produced pure oxygen is employed, it will be evident that no contamination thereof is allowable. The oxygen stream is therefore not switched between any chambers. The crOSs sections of the chambers for the oxygen streams and for the fourth streams are dictated by the allowable pressure drop in the two streams.

Inasmuch as the process involves temperatures of some minus 250 degrees Fahrenheit, a special material, such as copper or aluminum is resorted to in constructing the heat exchanger apparatus. To obtain a unit of low cost and weight, an aluminum alloy has been found preferable as the On accountmost suitable material. This material is castable and weldable, and thus ha two desirable features for a simple design.

While there has been hereinbefore described an approved embodiment of this invention, it will be understood that many and various changes and modifications in form, arrangement of parts and details of construction thereof may be made without departing from the spirit of the invention and that all such changes and modifications as fall within the scope of the appended claims are contemplated as a part of this invention.

The invention claimed and desired to be secured by Letters Patent is:

1. A method of cooling air which consists in passing stream of said air each along a passing stream of relatively cold nitrogen, passing a minor number of said air streams each along another passing stream of relatively cold nitrogen, and passing at least some of the remainder of said air streams each along a passing stream of relatively cold oxygen, and quenching said first mentioned passing streams of nitrogen prior to their said passing by said other streams of nitrogen subsequent to said passing of saidother streams of nitrogen.

2. A method of cooling air which consists in passing confined streams of atmospheric air each along a passing confined stream of relatively cold nitrogen, no two of said air streams bein adjacent and no two of said nitrogen streams being adjacent, passing a minor number of said air streams each along another passing confined stream of relatively cold nitrogen, and passing at least some of the remainder of said air streams each along a passing confined stream of relatively cold oxygen, quenching said first mentioned passing streams of nitrogen prior to their said passing by said other streams of nitrogen subsequent to said passing of said other streams of nitrogen, and prior to said quenching transferring said air and said first mentioned nitrogen streams so that said air streams flow through the confines previously containing said first mentioned nitrogen streams and said first mentioned nitrogen streams flow through the confines previously containing said air streams for defrosting said last mentioned confines by said first mentioned nitrogen streams of frost formed during cooling of said air therein.

3. A method of cooling air by relatively cold nitrogen and relatively cold oxygen which consists in passing confined streams of said air along confined streams of said cold nitrogen and confined streams of said cold oxygen thereby heating said streams of cold nitrogen and cold oxygen, passing other confined streams of said air along other confined streams of said cold nitrogen thereby heating said other streams of cold nitrogen, quenching some of said heated other stream of cold nitrogen into said first mentioned streams of cold nitrogen before said heating thereof for initially partially heating said first mentioned cold nitrogen streams before they are brought into heat exchange relation with said air streams, the consequent cooling of said air streams frosting the means confining said air streams, and thereafter defrosting said air confining means by alternating said air streams with said first mentioned and said nitrogen streams, said first mentioned and said nitrogen streams then being passed through said air confining means.

4. A method of cooling air at substantially pounds per square inch pressure from substantially 100 degrees Fahrenheit to substantially 250 degrees Fahrenheit by cold nitrogen at substantially 10 pounds per square inch pressure and 266 degrees Fahrenheit and cold oxygen at substantially 10 pounds per square inch pressure and 288 degrees Fahrenheit which consists in passing confined streams of said air along confined streams of said cold nitrogen and confined streams of said cold oxygen thereby heating said streams of cold nitrogen and cold oxygen, passing other confined streams of said hot air along other confined streams of said cold nitrogen at said substantially 10 pounds per square inch pressure and said 266 degree Fahrenheit, thereby heating said other streams of cold nitrogen to substantially degrees Fahrenheit, quenching said heated other streams of cold nitrogen into said first mentioned streams of cold nitrogen before said heating thereof for initiall partially heating to substantially 258 degrees Fahrenheit said first mentioned cold nitrogen streams before they are brought into heat exchange relation with said air streams, the consequent cooling of said air streams dropping their temperature to said substantially 250 degrees Fahrenheit, said cooling of said air streams frosting the means confining said air streams, and thereafter defrosting said air confining means by alternating said air streams with said nitrogen streams, said nitrogen streams then being passed through said air confining means.

WALTER GLOYERQ References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,460,859 Trumpler Feb. 8, 1949 2,529,013 Gloyer Nov. 7, 1950 2,537,276 McMahon Jan. 9, 1951 2,579,498 Jenny Dec. 25, 1951 2,586,811 Garbo Feb. 26, 1952