US3208510A

US3208510A - Heat exchanger

Info

Publication number: US3208510A
Application number: US299611A
Authority: US
Inventors: Ohnoda Katsuyuki; Fujisaki Masaya
Original assignee: Shin Mitsubishi Heavy Industries Ltd
Current assignee: Shin Mitsubishi Heavy Industries Ltd
Priority date: 1963-03-12
Filing date: 1963-08-02
Publication date: 1965-09-28
Anticipated expiration: 1982-09-28

Description

Sept. 28, 1965 KATSUYUKI OHNODA ET AL 3,208,510

HEAT EXCHANGER Filed Aug. 2, 1965 Fig./.

United States Patent 3,208,510 HEAT EXCHANGER Katsuyuki Ohuoda, Mizuho-ku, Nagoya, and Masaya Fujisaki, Narumi-gho, Aichi-gun, Aichi-ken, Japan, assign'ors to Shin-Mitsubishi Jukogyo Kabushiki Kaisha, Tokyo, Japan. Filed Aug. 2, 1963, 'Ser. No. 299,611 Claims priority, application Japan, Mar. 12, 1963, 38fi11,417 6 Claims. (Cl. 165-51) The present invention relates to heat exchange apparatus and more particularly to heat exchange apparatus for engines such as turboengines, turboprops, jet engines, and the like.

In recent aircraft, a conventional heat source is required for the purpose of removing ice from the plane as well as for providing heat inside the plane. In large jet planes for passengers, bleed air from the jet engine is utilized for this purpose, but in small turboprop airplanes, due to a shortage of bleed air, another heat source is necessitated.

Generally, in order to meet the deficiency of the heat source, the exhaust gas from the engine has been used to operate a heat exchange apparatus for heating the air utilized for said purpose. However, such heat exchange apparatus is bulky often causing rearrangement of equipment.

Therefore, it is an object of the present invention to provide heat exchange apparatus without such defects as mentioned above.

Another object of the present invention is to provide heat exchange apparatus incorporated in the tail pipe of the engine as a part thereof.

To this end, there is contemplated heat exchange apparatus which comprises a tail pipe, a cylindrical cover surrounding said tail pipe and defining a space between said tail pipe and said cover, an exhaust gas intake device providing communication between the inside of said tail pipe and said space, an exhaust gas outlet device to permit outflow of exhaust gas from said space, an intake device and an outlet device for air to be heated, each of which opens into said space, and heat transfer means mounted in said space between the tail pipe and the cover and defining closed chambers in said space, each in communication with a respective air device, said heat transfer means including means for conveying air from the chamber associated with the air intake device to the chamber associated with the air outlet device in heat exchange relation with said heated gases, but without contacting the same.

In the present invention as mentioned above, the exhaust gas and the air to be heated, both being fed to the space, are separated from each other in said chambers. Consequently, the air inducted into the space by the intake device and discharged from said outlet device may be heated, when it passes in said space between the chambers, by the exhaust gas of high temperature inducted from the exhaust gas intake device, thereby eliminating the need for a separate heat source. Furthermore, the exhaust gas and the air to be heated are separated from each other, eliminating any mixing together thereof in said space.

Further, according to the present invention, since a part of the tail pipe itself constitutes the heat exchange apparatus, both space and cost for equipment may be economized, compared with known heat exchange apparatus.

Therefore, it is an advantage of the present invention that space and cost for equipment can be reduced.

Other objects and advantages are obtained by the present invention as will be apparent from the following de- "Ice scription taken in connection with the accompanying drawings, in which:

FIG. 1 is a longitudinal side section showing an embodiment of the present invention;

FIG. 2 is a vertical cross section, along the line lIII in FIG. 1; and

FIG. 3 is an enlarged perspective view of a portion of the device of FIG. 1 and FIG. 2.

In the drawings, 1 is a tail pipe of a turboprop engine or a jet engine 2, the outer periphery of which is circumferentially surrounded by a cylindrical cover 4 to form an annular space covering openings 3 in the tail pipe. Exhaust gas from inside the tail pipe 1 passes through the openings 3 formed in said tail pipe 1. At the tail end of said cylindrical cover 4, an outlet device for exhaust gas is constituted of a port 6 having a butterfly valve 5 fitted therein.

In the diametrically opposed upper and lower ends of said annular space, are formed

chambers

7 and 7, having longitudinal side plates 11, 11' respectively connected to the cylindrical cover 4 and the tailpipe 1.

Transverse end plates

12, 12 extend across the annular space between side plates 11, 11' to thereby completely isolate the chambers 7, 7' from the flow of exhaust gas. Between said opposed side plates of the upper and

lower chests

7, 7 are two groups of a number of stainless steel air conduits 8, 8' which arcuately curve and peripherally extend along the said annular space, said conduits being connected to the side plates 11, 11 and open into said chambers 7, 7' as seen in FIG. 3.

Moreover, on said cylindrical cover 4, an intake port 9 and an outlet port 10 for air to be heated are arranged respectively communicating with the

chambers

7, 7 The chamber 7' and the intake port 9, and the chamber 7 and the outlet port 10 are respectively in communication whereby the air can flow from port 9 to port 10 via conduits 8 and be heated by the exhaust gases when passing through said conduits. Accordingly, when the butterfly valve 5 fitted to the inside of the exhaust port 6 for the exhaust gas is opened, the high temperature exhaust gas from the engine flows into the annular space through the openings 3 of the tail pipe 1, and, passes through the air conduits 8, 8', to be discharged from the exhaust port 6 via the butterfly valve 5; on the other hand, the air introduced through the intake port 9 into the chamber 7' in said annular space passes through the

conduits

8, 8, while being heated by said exhaust gas of high temperature passing outside thereof, and flows into the chamber 7 and then is discharged from the outlet port 10 and utilized as desired. Thus, the operation is effected without mixture of the exhaust gas and the air while heat exchange between the exhaust gas and the air is satisfactorily achieved.

In the abovementioned embodiment, though the tubular walls of

conduits

8, 8 are utilized as heat-transfer walls, various other constructions may optionally be adopted as heat transfer walls.

It will be clear to those skilled in the art that the invention is not limited to the specific construction disclosed herein, but covers various modifications and variations without departing from the spirit of the invention as defined in the accompanying claims.

What is claimed is:

1. Heat exchange apparatus for the tail pipe of an engine employing the tail pipe itself as a part of the apparatus, said apparatus comprising a cover including a cylindrical portion, said tail pipe having an outer surface, said cover being on and surrounding said outer sur face of the tail pipe to define therewith a closed space between the cover and tail pipe, said tail pipe having an opening therein establishing communication between the interior of the tail pipe and the said space such that exhaust gas within the tail pipe will flow into said space, outlet means on said cover at a location spaced from said opening for the selective discharge of exhaust gas from within said space whereby with said outlet means open exhaust gas will flow through said space, means defining enclosed chambers at diametrically opposed locations in said space at a position between the opening in the tail pipe and the outlet means, said chambers being isolated from the passage of exhaust gas, said cover having an opening in communication with a respective chamber, a plurality of curved heat exchange tubes extending between and in communication with said chambers for the passage of a fluid, one of said chambers constituting an inlet for the fluid, the other of the chambers constituting an outlet for the fluid, the exhaust gases flowing around said tubes and in heat exchange relation with the fluid in said tubes as the exhaust gases flow from said opening in the tail pipe to the outlet means, the fluid flowing from said inlet to the outlet via said tubes and being heated by the exhaust gases during said flowing, said means defining the chambers including, for each chamber a pair of spaced longitudinally extending side plates secured between the outer surface of the tail pipe and the cylindrical portion of the cover and coupled to the heat exchange tubes to permit passage of fluid between the tubes and the chamber.

2. Heat exchange apparatus comprising a tail pipe adapted for conveying heated gases, a cylindrical cover surrounding said tail pipe and defining a space between said tail pipe and said cover, an exhaust gas intake device providing communication between the inside of said tail pipe and said space whereby heated gas from said tail pipe can flow outwardly and enter said space, an exhaust gas outlet device in said cover to permit outflow of exhaust gas from said space, whereby heated exhaust gas can pass through said space, an intake device for air to be heated and an outlet device on said cover for heated air, each of which opens into said space, heat transfer means mounted in said space between the tail pipe and the cover and defining closed chambers in said space each in communication with a respective air device, said heat transfer means including means for conveying air from the chamber associated with the air intake device to the chamber associated with the air outlet device in heat ex- 4- change relation with said heated gases but without contacting the same, said heat transfer means isolating the chambers from the flow of exhaust gas.

3. Apparatus as claimed in claim 2, wherein said exhaust gas intake device is constituted by a plurality of circumferentially arranged openings in said tail pipe.

4. Apparatus as claimed in claim 2, wherein said air intake and outlet devices are diametrically located on said cover.

5. Apparatus as claimed in claim 2, wherein said means for conveying air between said chambers comprises a plurality of conduits extending between said chambers for the conveying of air which is heated by the passage of gas past said conduits.

6. Apparatus as claimed in claim 5, wherein said heat transfer means comprises a pair of longitudinal side plates between the cover and tail pipe bounding each chamber, said side plates supporting the conduits and enabling the latter to open directly into the respective chambers, transverse end plates positioned between the cover and tail pipe and extending between the side plates of each chamber to combine with the side plates to completely isolate the chambers from the flow of exhaust gas.

References Cited by the Examiner UNITED STATES PATENTS 1,068,094 7/13 Bailey et a1. 23712.3 1,851,691 3/32 Yaeger 156 X 2,458,159 1/49 Goldthwaite 165-125 X 2,519,496 8/50 Norman 165125 X 2,828,946 4/58 Smith 165154 X FOREIGN PATENTS 616,659 1/49 Great Britain. 710,381 6/31 France.

OTHER REFERENCES Utilization of Exhaust Heat Exchanger Installations, by P. A. Pitt, from the March 1, 1945, issue of the Aero Digest.

ROBERT A. OLEARY, Primary Examiner.

CHARLES SUKALO, Examiner.

Claims

2. HEAT EXCHANGE APPARATUS COMPRISING A TAIL PIPE ADAPTED FOR CONVEYING HEATED GASES, A CYLINDRICAL COVER SURROUNDING SAID TAIL PIPE AND DEFINING A SPACE BETWEEN SAID TAIL PIPE AND SAID COVER, AN EXHAUST GAS I NTAKE DEVICE PROVIDING COMMUNICATION BETWEEN THE INSIDE OF SAID TAIL PIPE AND SAID SPACE WHEREBY HEATED GAS FROM SAID TAIL PIPE CAN FLOW OUTWARDLY AND ENTER SAID SPACE, AN EXHAUST GAS OUTLET DEVICE IN SAID COVER TO PERMIT OUTFLOW OF EXHAUST GAS FROM SAID SPACE, WHEREBY HEATED EXHAUST GAS CAN PASS THROUGH SAID SPACE, AN INTAKE DEVICE FOR AIR TO BE HEATED AND AN OUTLET DEVICE ON SAID COVER FOR HETED AIR, EACH OF WHICH OPENS INTO SAID SPACE, HEAT TRANSFER MEANS MOUNTED IN SAID SPACE BETWEEN THE TAIL PIPE AND THE COVER AND DEFINING CLOSED CHAMBERS IN SAID SPACE EACH IN COMMUNICATION WITH A RESPECTIVE AIR DEVICE, SAID HEAT TRANSFER MEANS INCLUDING MEANS FOR CONVEYING AIR FROM THE CHAMBER ASSOCIATED WITH THE AIR INTAKE DEVICE TO THE CHAMBER ASSOCIATED WITH THE AIR OUTLET DEVICE IN HEAT EXCHANGE RELATION WITH SAID HEATED GASES BUT WITHOUT CONTACTING THE SAME, SAID HEAT TRANSFER MEANS ISOLATING THE CHAMBERS FROM THE FLOW OF EXHAUST GAS.