US3587732A

US3587732A - Heat exchanger formed by modules

Info

Publication number: US3587732A
Application number: US862131A
Authority: US
Inventors: Frederick A Burne
Original assignee: Olin Corp
Current assignee: Olin Corp
Priority date: 1969-08-14
Filing date: 1969-08-14
Publication date: 1971-06-28
Anticipated expiration: 1988-06-28

Abstract

A HEAT EXCHANGER IS FORMED OF HEAT EXCHANGER UNITS WHICH EACH HAVE A SECTION OF THE HEADER AND A POROUS MATERIAL WITH A MULTIPLICITY OF TUBES EMBEDDED THEREIN WITH THE TUBES COMMUNICATING WITH THE HEADER SECTION. THE UNITS ARE ASSEMBLED AND JOINED TOGETHER TO FORM HEADERS.

Description

United States Patent HEAT EXCHANGER FORMED BY MODULES 5 Claims, 11 Drawing Figs,

U.S..Cl 165/158, 29/157.4,165/159, 165/164,165/175 Int. Cl F281 9/02, F28f1/10 Field Search 165/175,

[56] References Cited UNITED STATES PATENTS 3,289.756 12/1966 Jaeger 165/180X 3,415,316 12/1968 BurneetalM 165/164 FOREIGN PATENTS 647,675 7/1928 France 165/164 701,144 1/1931 France 165/158 882,095 7/1953 Germany 165/160 144,659 1/1952 Australia 165/158 Primary ExaminerA1bert W. Davis, Jr. Anorneys- Henry W. Cummings, Robert H. Bachman, Arthur N. Krein, Richard S. Strickler and George .1. Koeser ABSTRACT: A heat exchanger is formed of heat exchanger units which each have a section of the header and a porous material with a multiplicity of tubes embedded therein with the tubes communicating with the header section. The units are assembled and joined together to form headers.

PATENTEDJUNZSIQYI cal-587,732

SHEET 1 0F 3 I INVENTOR; FREDERICK/1. BURNE ATTORNEY PATENTED JUN28 19m SHEET 2 UF 3 INVEN'I 0R: FREDERICK A. BU/PNE ATTORNEY PATENTEU Junzs I971 SHEET 3 BF 3 INVENTOR: FREDERICK/1. BURNE III/l ATTORNEY HEAT EXCHANGER FORMED BY MODULES This application is a division of copending application Ser. No. 692,913, filed Dec. 22, 1967, now abandoned.

This invention relates to heat exchangers.

In particular, it relates to the type of heat exchanger described in U.S. Pat. No. 3,289,756 issued to U. R. .laeger. In this patent a heat exchanger is described in which a plurality of tubes are conductively bonded to a body of pervious material. One heat exchange medium passes through the tubes while another heat exchange medium passes radially through the pervious material providing extended surface and an efficient, compact heat exchanger.

In US. application SerfNo. 629,954 of Burne and Valyi, filed Apr. ll, I967 and assigned to the same assignee as the present invention, modular units having a tube conductively bonded to a layer of porous material are described. The invention in Ser. No. 629,954 allows the production of units of extended length due to the modular construction.

The object of the present invention is to allow the production of modular units of indefinite length, and will, furthermore, allow great quantities of the heat exchange medium to be heated or cooled and passed through the heat exchanger with very low pressure drop.

In the drawings, FIG. 1 is a section along the lines 1-1 in FIG. 2.

FIG. 2 is a section along the lines 2-2 in FIG. 1.

FIG. 3 is a partial end view of header 20.

FIG. 4 is a partial view of the header 30.

FIGS. 5A and 5B are front and side views respectively of the header 40.

FIGS. 6A and 6B are front and side views of the headers 50.

FIG. 7 is a sectional view. of another embodiment of the present invention.

' FIG. 8 is a sectional view along the lines 8-8 in FIG. 7.

FIG. 9 is an end view of header 500.

In FIGS. 1 and 2, a heat exchanger is shown in which a plurality of tubes 90 are conductively bonded to porous material 80, as shown in FIG. 2, a plurality of these tubes bonded to porous material constitute module units 100. In addition, the modular units 100 contain a center conduit I0. A plurality of these units I are placed within a shell 70. However, before placement in the shell, the

headers

40 and 50, as shown in FIGS. A, 53, 6A and 6B are attached to each end of the units 100.

The header 40 has a plurality of openings M to receive the tubes 90 for each unit. Additionally, there is an opening 42 which cooperates with cavity 10. As can be seen from FIG. I, there is a portion 91 of the tubes 90 which does not have porous material 80 conductively bonded thereto. The headers 40 are placed upon the units 100 and the layer of porous material 80, the portions 91 of tubes 90 extending through the openings 41, and the openings 42 lining up with the conduits 10 in the units 100'.

It can also be seen from FIG. I that there is a second end portion 92 of tubes 90 which does not have a layer of porous material conductively bonded thereto. The headers 50 having openings 51 are placed upon this end of the units I00, with the end portion 92 of the tubes passing through openings 51. However, it is apparent that header 50 differs from header 40 in that there is no center opening in header 50.

As can also be seen in FIG. I, the tube end portions 91 of the units 100 are sealingly received, such as by welding, in a large header 20. Header is'shown in a partial end view in FIG. 3. This header has a plurality of openings 21, 22, 23, 24 and 25 for the tubes from each of the units 101, I02, I03, I04, and 105 shown in FIG. 2. It is thus apparent that the header 20 receives all the tube end portions from all the units in the heat exchanger.

However, it is emphasized that, if desired,'the end portions 91 could be received in small headers such as 50, which small headers wouldthen be received in headers such as shown in FIG. 4 and appropriately sealed thereto.

As also can be seen from FIG. I inwardly from header 20, a 9

on each of the units. Thus, as can be seen from FIG. 4, the header 30 has a plurality of

openings

31, 32, 33, 34 and 35 corresponding to the headers 40, shown in FIGS. 5A and 58.

There is provided at the other end of theheat exchanger a second header 60, having the same shape as the header 30, which receives the corresponding end headers 50. Thus, each of the units 101, I02, 103, 104 and 105 is received in a corresponding end header 50 having the configuration shown in FIGS. 6A and 6B. The headers 50, in turn, fit into the large header 60 in the same way that the headers 40 are received in header 30.

The shell 70 has end plates 71 which fit on either end of the heat exchanger. Also, there are two inlet conduits 72 and 73, and outlet conduits 74 and 75 as shown in FIG. 1. Obviously, additional inlet and outlet conduits could be provided, if

desired. I

The header plate 71 together with header 20 define an inlet chamber 11 which communicates with inlet conduit 72. Similarly,

headers

20 and 30 define a second inlet chamber 12 which communicates with inlet 73. In like manner, end plate 7 I and header 60 define an outlet chamber 13 which communicates with outlet conduit 75. Outlet conduit 74 communicates with outlet chamber 14 defined by shell 70 and headers 30 and 60.

Thus, in an exemplary embodiment of the present invention, water from any convenient source is introduced into one or more conduits 73. The water then passes through chamber 11 into end portion 91 of tubes 90, through

headers

20 and 30 and 60, into exit chamber 13, and out through one or more conduits 75, having absorbed or rejected heat during the passage through tubes 90.

At the time, a heat exchange medium to be heated or cooled, for example, oil to be cooled, is introduced through one or more conduits 73 into inlet chamber 12. From there, it passes into center conduit 10 through openings 42 in the headers 40. From the chamber 10 the oil passes radially outwardly through porous material 80. During its radial passage through porous material 80, the oil is in heat exchange relation with the heat exchange medium (i.e., cooling water) passing through tubes and loses or gains heat by way of the porous matrix and tube wall. After the oil exits from porous material 80, it passes into exit chambers 10 and/or 16 or 17 shown in FIG. 2, and is collected in chamber 14. From there it exits through one or more conduits 74. From there, the oil can either be additionally cooled or put back in service. Obviously, other heat exchange media, including gases, could be process, instead of water and oil.

According to one method of assembling the heat exchanger of FIG. 1, the tubes 90 are first placed in

headers

40 and 50. A brazing compound may be placed on the tubes as they are fitted into the headers. The units with

headers

40 and 50 in place are next fitted with a screen or core to define the cavity 10. This assembly is placed in a mold and shot, also particulate material such as containing brazing material is poured into the mold. This assembly is then placed in a brazing furnace and heated to appropriate temperatures and time for the particularshot material to form pervious layers 80.

The units are then removed from the furnace and if a core is used to define channel 10, the core is removed at this point. Of course, if a screen is used, it need not be removed. I

The units are next fitted into the

larger headers

20, 30, and 60. Either a small header or the tube ends 93 are received in header 20. Header 30 receives headers 40. Headers 60 receive headers 50. Appropriate seals are provided at these points. After sealing, for instance, by brazing or welding the entire core is placed within a shell 70 and the

headers

20, 30 and.60. scaled to shell 70, for example, by brazing or welding. Appropriate conduits such as 72, 73, 74 and 75 which have already been provided on the shell 70 may then be appropriately connected.

FIGS. 7 and 8 show another embodiment of the present invention. As seen in this embodiment, a plurality of tubes 900 are conductively bonded to a body of porous material 800.

Thus, the

heat exchange portions

1010, 1020 and 1040 are very similar to those in FIGS. 1 and 2. However, the

units

430, 440, 450 and 460 are made up of the cores together with pie section headers. Thus, the

headers

200, 500 and 300 shown in FIG. 8 are made up of pie quarter sections. As can be seen from the double section in FIG. 7,

quarter sections

230 and 260 are shown defining half of header 200, while

quarter sections

540 and 550 define half of header 500. Header 500 is shown more clearly in FIG. 9 in which all portions of header 500,

quarter sections

530, 540, 550 and 560 appear. The pie sections are held together by welds 270 and $70.

In order to form the units shown in FIGS. 7 and 8, the tubes 900 are placed in the quarter section headers. Appropriate sealing means, for example, brazing material, is provided on the tubes. The quarter sections with the tubes in place are then placed in a mold which defines the desired cross section of the

portions

1010, 1020, 1030 and 1040, with either a tubular screen or core to define the center 100. Shot material for forming the porous body 800 together with a brazing compound to bond the shot together and to the quarter section headers are poured into the mold. After the shot and brazing material are placed in the mold, the quarter section units are placed in a brazing furnace and heated to the appropriate temperature and time for the particular brazing material and shot material. The porous body is thus formed and the porous body is bonded to the pie section headers. After removal from the furnace, the cores are removed from the units. If a screen is used, of course, it is not necessary to remove the screen. This results in quarter section units such as 430, 440, 450 and 460.

In order to assemble an entire heat exchanger core, the units are merely welded together, as at 270 and 570. Welding is also carried out to define header 300. The so-welded together core is then slid into shell '700 and is soldered or brazed in place. The shell ends 710 and 720 can then be attached to the shell 700 in an appropriate manner, such as by brazing or by welding.

The heat exchanger operates as follows. One heat exchange medium (for example, water) is introduced at 720, passes through tubes 900 and leaves through chamber I30 through outlet 750. A heat exchange medium to be heated or cooled (for example, oil) is introduced at 730. It passes radially inwardly to center 100 in the chamber 120. During its passage therethrough, heat is exchanged with the heat exchange medium and passes through tube 900. The second heat exchange medium passes through header 500 through opening 510 therein and into chamber 140. As the second heat exchange medium passes radially outwardly from the center 100, it is again in heat exchange relation with the first heat exchange medium passing through tubes 900. The second heat exchange medium collects. in the outer portion of chamber 140 and leaves through conduit 740.

It is apparent that this is a double pass unit because heat is exchanged between the second heat exchange medium and first heat exchange medium during the passage inwardly to channel 100 in chamber 120 and during the outward passage from channel 100 in chamber 140.

It is also apparent that the parallel flow which takes place in such a heat exchanger (the flow through units 430 is parallel to the flow through

units

440 and 450, etc.) provides for a low pressure drop.

The method of sealing the tubes to the small headers, the small headers to the large headers, and the headers to the shell in addition to brazing, could be done by an O-ring seal in an substantially all of the medium to be heated or cooled is in heat exchange relationship with the heat exchange medium passing through the tubes.

Furthermore, the units can be manufactured in long lengths if desired. The cross section size of each unit is small enough to so that uniform brazing of the porous material can be obtained. Thus, the size of this heat exchanger is not limited by the brazing operation.

It is to be understood that the invention is not limited to the illustrations described and shown herein which are deemed to be merely illustrative of the best modes of carrying out the invention, and which are susceptible of modifications of forms, size, arrangement of parts and detail of operation, but rather is intended to encompass all such modifications which are within the spirit and scope of the invention as set forth in the appended claims.

I claim: v

l. A heat exchanger comprising:

a heat exchange core which is characterized in that it contains a plurality of units, each unit comprising a porous body having a centrally located conduit therein, a plurality of tubes radially disposed about said conduit, said tubes being conductively bonded within said porous body, each unit further having at least one pie-shaped header section which communicates with said tubes, said units being assembled into said heat exchange core with said header sections being interfittingly connected to define a complete header;

means communicating with said tubes for passing a first heat exchange medium through said tubes;

means communicating with said tubes for collecting said first heat exchange medium after it is passed through said tubes;

means communicating with said porous body for passing a portion of a second heat exchange medium through said porous body of each of said units in a general radial direction; and

means communicating with said porous body for collecting said second heat exchange medium after it has passed through said porous body.

2. A heat exchanger according to claim 1 wherein said means for passing said second heat exchange medium through said porous body comprises a first means for passing said second heat exchange medium through said porous body in a general radial direction into said centrally located conduit and a second means for passing said second heat exchange medium out from said conduit through said porous body in a general radial direction.

3. A heat exchanger according to claim 1 wherein said header sections are pie-shaped.

4. A heat exchanger according to claim 1 wherein said header sections are connected by being welded together.

5. A heat exchanger according to claim 1 wherein said.

header sections are connected by being brazed together.