US3163210A

US3163210A - Heat exchanger

Info

Publication number: US3163210A
Application number: US32474A
Authority: US
Inventors: Rex A Horrocks
Original assignee: United Aircraft Corp
Current assignee: RTX Corp
Priority date: 1960-05-27
Filing date: 1960-05-27
Publication date: 1964-12-29
Anticipated expiration: 1981-12-29

Description

Dec- 1964 R. A. HORROCKS HEAT EXCHANGER Filed May 27, 1960 INVENTOP REX A. HORROGKS Wm ATTORNEY United States Patent This invention relates to a heat exchanger construction. One feature of the invention is an arrangement of a plurality of heat exchanger tubes such that they are held in spaced parallel relation to one another by spacer strips positioned among the tubes. Another feature is the assemblage of the spacers and tubes such that each tube extends helically from end-to-end to assure better surface contact with the fluid flowing around the tubes.

One feature is the assemblage of the tube and spacers in an elongated tank with the flow of one fluid through the tubes and with the other fluid for the heat exchanger flowing around the tubes within the tank. Another feature is the formation of the tubes and tank into a helical coil for conservation of space. Another feature is the use of an elongated tank through which the helically arranged and spaced apart tubes extend from end-to-end regardless of the configuration of the elongated tank.

Other features and advantages will be apparent from the specification and claims, and from the accompanying drawing which illustrates an embodiment of the invention.

FIG. 1 is an end elevation of a heat exchanger.

FIG. 2 is a side elevation of a part of the exchanger of FIG. 1 with parts broken away.

FIG. 3 is a sectional view through a coil of the heat exchanger.

The heat exchanger is in the form of a helically coiled elongated tank 2 having end caps 4;and 6 at opposite ends. Each cap has an axially positioned inlet and discharge pipe 8 or 10 for one of the fluids and lateral inlet ample, is diverted by the header 16 into the tubes 20 and flows through these tubes from one{ end of the tank to;

the other to discharge into the other cap 6 and thence through the pipe 10. The other fluid is directed to the tank outside of the tubes 20 and flows from end-to-end of the tank around the tubes to .be discharged through the connection 12.

The tubes 20 extend in parallel relation to each other and in uniforrnally spaced relation being held in spaced relation to one another by a plurality of parallel elongated strips 22 extending from one header to the other. Each of these strips 22 is of uniform width from end-to-end and is twisted along its longitudinal center line so that each strip forms a helix about its own center line. In

the arrangement shown, the twist of these strips is such'

headers

16 and 18 are twisted with respect to each other about a longitudinal axis centrally of the assemblage of tubes and spacers so that helices having an opposite twist or hand to the original twist of hand" of the spacers is'formed with each of the tubes andspacers. If the original twist of the spacers produces a left-hand'helix, as above stated, then the twist imparted to the tubes and spacers about the longitudinal axis 25 of the assemblage In each case the resulting:

will be right-hand helices. tubes are in the form of helices, the axes of which are spaced from the tube and the tubes and spacers are both twisted to the same extent and thus have the twist from end-to-end.

When this assemblage of the helically arranged spacers and tubes is positioned within the tank, it will be apparent that the fluid flowing through the tank externally of the tubes Will be in more contact' with the walls of the tube than would be the case if the tubes were not helically arranged. 3

In describing the assemblage of tubes and spacers, they have been described so far as if the assemblage were arranged about a straight axis. The assemblage is then positioned within the surrounding tube 2, the latter preferably being at this time also straight and the

headers

16 and 18 are secured in position. The tank with the tube and spacer assemblage therein is then wrapped into the coil configuration ofFIGS. l and 2 in which the radius of the hel x is substantially greater than thediameter of the tube, as will be apparent, and the adjacent coils of the helix are in closely spaced relation to one another, as shown in FIG. 2.

It is to be understood that the invention is not limited to vthe specific embodiment herein illustrated and described, but may be used in other ways without departure from its each strip in contact therewith to hold the tubes in spaced relation, each spacer being in the form of a helix coinciding substantially with the longitudinal center line of each strip, a header at the end of each set of tubes to which the spacers and tubes are attached, each of said tubes being in the form of a helix between the ends thereof, the axis of each tube helix being spaced. from .the

center of each tube, and a surrounding elongated'tank in which the assemblage of tubes andspacers is positioned,

, each stripin contact therewith to hold the tubes in spaced as to form a left-hand helix. As will be apparent, these engagement of opposite edges of the spacers with the tubes;

After the spacers 22 and the tubes 20 have been assembled, they are wrapped witha helically extending wire 24 which being attached at opposite ends to the

headers

16 and 18 will hold the tubes and the spacers snugly together.

After the tubes and spacers have been assembled, the

relation, each spacer being in the form of a helix coinciding substantially with the longitudinal center line of each strip, a header at the end of each set of tubes to which the spacers and tubes are attached, each of said tubes being in the form of a helix between the ends ing substantially greater than the diameter of the tank.

(References on following page) 3,163,210 Patented Dec. 29, 1964 UNITED STATES PATENTS Johns Oct. 6, 1896 Lahgsenkamp D0017, 1918 Sullivan Apr.15, 1932 Belt Jan. 10, 1933 Bottoms June 27, 1933,

. Swart Nov. 24, 1936 Dolison Nov. 15, 1938 Cohler Dec. 16, 1952 FOREIGN PATENTS Switzerlafid June 1, 1942 Great Britain May 6, 1926 Canada Mar. ,29, 1955 France -j Apr. 3,1956

Claims

1. A HEAT EXCHANGER INCLUDING A PLURALITY OF PARALLEL TUBES SPACED SUBSTANTIALLY UNIFORMALLY FROM EACH OTHER, SPACERS IN THE FORM OF STRIPS POSITIONED AMONG AND IN PARALLEL RELATION TO THE TUBES AND WITH OPPOSITE EDGE OF EACH STRIP IN CONTACT THEREWITH TO HOLD THE TUBES IN SPACED RELATION, EACH SPACER BEING IN THE FORM OF A HELIX COINCIDING SUBSTANTIALLY WITH THE LONGITUDINAL CENTER LINE OF EACH STRIP, A HEADER AT THE END OF EACH SET OF TUBES TO WHICH THE SPACERS AND TUBES ARE ATTACHED, EACH OF SAID TUBES BEING IN THE FORM OF A HELIX BETWEEN THE ENDS THEREOF, THE AXIS OF EACH TUBE HELIX BEING SPACED FROM THE CENTER OF EACH TUBE, AND A SURROUNDING ELONGATED TANK IN WHICH THE ASSEMBLAGE OF TUBES AND SPACERS IS POSITIONED, SAID TANK AND THE HELICALLY ARRANGED TUBES AND STRIPS THEREIN BEING ARRANGED IN A HELICAL COIL, THE AXIS OF WHICH IS EXTERNAL OF THE TANK.