US3732921A

US3732921A - Heat exchanger

Info

Publication number: US3732921A
Application number: US00158297A
Authority: US
Inventors: E Hilicki; H Schroeder
Original assignee: Modine Manufacturing Co
Current assignee: Modine Manufacturing Co
Priority date: 1971-06-30
Filing date: 1971-06-30
Publication date: 1973-05-15
Anticipated expiration: 1990-05-15
Also published as: CA940116A

Abstract

A heat exchanger in which the exchanger comprises inner and outer tubes spaced apart to define a fluid passage but sealed at the opposite extremities of the passage, a pair of spaced fittings communicating with the fluid passage for flow of fluid into, through and from the passage, a fluid turbulizer in the passage comprising flat stock with laterally projecting integral strips to create turbulence in the fluid flowing through the passage and resulting superior heat transfer with the turbulizer having end portions terminating short of the extremities of the passage to define a pair of end header spaces and a direct flow path from one fitting means and the nearer header space in collapsed or flattened condition so that the strips in this area provide substantially no impediment to fluid flow from the fitting means to the nearer header space.

Description

United States Patent [191 Hilicki et al.

[ 1 May 15, 1973 [54] HEAT EXCHANGER [75] Inventors: Edwin J. Hilicki, Racine, Wis;

Harry J. Schroeder, Lake Bluff, ill.

[73] Assignee: Modine Manufacturing Company,

Racine,Wis.

[22] Filed: June 30, 1971 [21] Appl. No.: 158,297

Jones Burne et al. ..l65/l54 Primary Examiner-Charles J. Myhre Assistant Examiner-Theophil W. Streule, Jr. A tt0rney- Axel A. Hofgren et al.

[57] ABSTRACT A heat exchanger in which the exchanger comprises inner and outer tubes spaced apart to define a fluid passage but sealed at the opposite extremities of the passage, a pair of spaced fittings communicating with the fluid passage for flow of fluid into, through and from the passage, a fluid turbulizer in the passage comprising flat stock with laterally projecting integral strips to create turbulence in the fluid flowing through the passage and resulting superior heat transfer with the turbulizer having end portions terminating short of the extremities of the passage to define a pair of end header spaces and a direct flow path from one fitting means and the nearer header space in collapsed or flattened condition so that the strips in this area provide substantially no impediment to fluid flow from the fitting means to the nearer header space.

4 Claims, 7 Drawing Figures 1 HEAT EXCHANGER BACKGROUND OF THE INVENTION The heat exchanger of this invention is related to the In FIGS. 1 and 2 there is disclosed a heat exchanger tubular types of heat exchanger in which a fluid flow comprising an outer tube 11, an inner tube 12 within path is provided between two tubes, one outer and one inner and spaced apart in a region to provide a fluid passage therebetween so that fluid can not only flow in this passage but other fluid may contact the inner and outer tubes to provide heat transfer between all of the fluids.

It is customaryto provide fluid turbulizers in this passage between the tubes and to provide spaced fittings for flow of fluid into, through and from the space and to have the turbulizers shorter than the space between the tubes so as to result in end header spaces that are free of the turbulizers.

In this invention the turbulizer which principally comprises laterally projecting strips of stock material has these strips collapsed in an area between one fitting means and the nearer header space so as to provide direct flow from the fitting means into the header space without substantial short-circuiting of the fluid directly from the fitting means into the turbulizer.

With the structure of this invention the confining of the flow from the fitting into the one header space is easily and inexpensively accomplished merely by flattening or collapsing the turbulence promoting strips in the desired area so that there is less resistance to fluid flow in this area then in the remainder of the turbulizer. With this invention the spacing of the fittings can be standardized to one distance and the cooling capacity can be increased or decreased by controlling the length of the heat exchanger tubes. Within a wide latitude the length of the heat exchanger can be any value desired because the collapsed turbulizer strips permit the directing of the fluid from the fitting to the adjacent header space regardless of the length. In general, only one collapsed area of turbulizer strip will be required for each heat exchanger but, if desired, each fitting may of course have its own direct flow path into its nearer header space by providing it with the collapsed strips.

The most pertinent prior art of which applicants are aware are Dedo U.S. Pat. No. 2,752,128, Straubing U.S. Pat. No. 3,001,767 and Zeidler U.S. Pat. No. 3,083,662 each of which discloses tubular heat exchanger with turbulizers made of expanded or distorted flat stock. However, in none of these are there provided direct flow paths of the type disclosed and claimed herein.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a shortened side elevational view partially in section illustrating a tubular heat exchanger embodying the invention.

FIG. 2 is a sectional view taken substantially along line 2-2 of FIG. 1.

FIG. 3 is an enlarged perspective view of a section of a turbulizer that may be used in this invention.

FIG. 4 is a fragmentary plan view of one end of turbulizer of this invention.

FIG. 5 is a side elevational view of the turbulizer of FIG. 4.

FIG. 6 is an end elevational view of the portion of the turbulizer of FIGS. 4 and 5.

FIG. 7 is a view similar to FIG. 6 but illustrating a further embodiment of the invention.

the

seal

14 and 15 at the opposite ends of the

tubes

11 and 12 to define the extremities of the fluid passage 13.

The heat exchanger is provided with a pair of spaced apart fitting means 16 and 17 in the form of ordinary pipe fittings for providing communication with the fluid passage 13. One fitting 16 is adjacent the end of the tube to communicate with a header space 18 while the other fitting 17 is spaced inwardly of the other end of the heat exchanger and from the other header space 19. These

fittings

16 and 17 are similar to the fittings in the above referred to patents in that they provide fluid flow into, through and from the fluid passage 13.

Positioned in the fluid passage 13 is a turbulizer 20 having ends terminating short of the passage 13 to provide the

end header spaces

18 and 19. This turbulizer customarily comprises laterally projecting integral strips so as to create turbulence in fluid flowing between and around the strips. Typical turbulizers are disclosed in the above patents and one type is shown in enlarged detail in FIG. 3 which illustrates only a fragment of a turbulizer. This type of turbulizer is disclosed in greater detail in Dedo U.S. Pat. No. 2,752,128 and it comprises flat stock 21 having

integral strips

22 and 23 projecting therefrom.

In the turbulizer of this invention a direct flow path is provided from one or both of the

fittings

16 and 17 directly to the nearer header space. In the embodiment of FIGS. 1 and 2 the one fitting 16 is located adjacent a header space 18 while the other fitting 17 is spaced from the other header space 19 and the direct flow path 24mm the fitting 17 to the nearer header space 19 is provided by collapsing or flattening these spaced turbulizer strips as illustrated at 22 and 23. i

In the embodiment of FIGS. 4, 5 and 6 this flattening of the expanded

metal strips

22 and 23 is into the plane of the flat stock as described and the resulting structure is corrugated as illustrated at 25 to provide parallel flow from the fitting 17 to the header space 19. Such corrugating is not required, however, although it does give added strength to the part. If desired, the corrugations may be omitted as illustrated in the embodiment of FIG. 7 so that the flat stock and collapsed strips are all in a single plane that follows the general curvature of the turbulizer thereby providing a large header reservoir 27. Actually, of course, the collapsed strips are in a common plane with each other and with thestock even in FIG. 6 which shows the corrugated construction. In FIG. 7 the collapsed coplanar strips are against the tube 12.

As can be seen from the above description, the heat exchanger of this invention provides an efficient but inexpensive heat exchanger that directs fluid from one or both of the fittings into the nearer header space without requiring added conduits, drains or the like. In the illustrated structure the

seals

14 and 15 defining the opposite ends of the fluid passage 13 are arranged by making the corresponding ends of the inner and outer tubes contiguous and joined together. This is easily accomplished by bending the ends of one or both tubes into the contiguous relationship as by enlarging the opposite ends of the inner tube 12 into contact with the inner surface of the outer tube 11 in the manner illustrated in FIG. 1.

As is illustrated in FIGS. 4-7 it is customary to provide the turbulizer in two semi-cylindrical sections so that when they are located within the fluid passage 13 they form generally a cylinder.

Having described our invention as related to the embodiments shown in the accompanying drawings, it is our intention that the invention be not limited by any of the details of description, unless otherwise specified, but rather be construed broadly within its spirit and scope as set out in the appended claims.

We claim:

1. A heat exchanger, comprising: an outer tube; an inner tube therein and spaced therefrom to define a fluid passage therebetween; a pair of spaced seal means between said tubes for defining opposite extremities of said passage; a pair of spaced fittings for directing a fluid in a stream to, through and from said fluid passage; a fluid turbulizer in said fluid passage extending substantially circumferentially there around and having projecting portions spaced from each other both laterally and longitudinally and spanning the passage, said turbulizer having end means for defining with said pas sage a pair of end header spaces; and means comprising collapsed said projecting portions adjacent a said fitting for providing a direct flow path at-said one fitting to the nearer of the header spaces.

2. The heat exchanger of claim 1 wherein said turbulizer comprises flat stock, and said collapsed said strips provide substantially parallel corrugated flow paths for rapid flow of fluid and added strength.

3. The heat exchanger of claim 1 wherein said collapsed strips are substantially coplanar to provide a header reservoir.

4. The heat exchanger of claim 1 wherein the opposite ends of said irmer tube are enlarged relative to the remainder of said inner tube to engage the outer tube and define the end limits of said header spaces.

Claims

1. A heat exchanger, comprising: an outer tube; an inner tube therein and spaced therefrom to define a fluid passage therebetween; a pair of spaced seal means between said tubes for defining opposite extremities of said passage; a pair of spaced fittings for directing a fluid in a stream to, through and from said fluid passage; a fluid turbulizer in said fluid passage extending substantially circumferentially there around and having projecting portions spaced from each other both laterally and longitudinally and spanning the passage, said turbulizer having end means for defining with said passage a pair of end header spaces; and means comprising collapsed said projecting portions adjacent a said fitting for providing a direct flow path at said one fitting to the nearer of the header spaces.

4. The heat exchanger of claim 1 wherein the opposite ends of said inner tube are enlarged relative to the remainder of said inner tube to engage the outer tube and define the end limits of said header spaces.