US2361691A - Heat exchanger for gas turbines - Google Patents

Description

Oct. 31, 1944. G. JENDRASSIK HEAT EXCHANGER FOR GAS TURBINES Filed April 15, 1959 the two fluids.

Patented a. 31, 1944 FFICE HEAT EXCHANGER FOR GAS mamas George Jendrasslk, Budapest, Hungary; vested in the Alien Property Custodian Application Apr-Q15, 1939, Serial No. 268,009 In Hungary April 16, 1938 2 Claims.

The invention relates to s, heat exchanger for use with a gas turbine and a compressor for preliminary compression of the working fluid. In plants oi. this character only moderate temperatures (500 to 600 deg. centigrade) are permissible, and it is therefore desirable to recover the heat of the spent gases from the turbine for use in heating the fresh working fluid from the compressor, in order to obtain greater'efiiciency. In this way the temperature of the fresh fluid of higher pressure leaving the heat exchanger to enter the turbine should approximate as far as possible the temperature of the spent gas of lower pressure leaving the turbine. This invention is designed to provide a heat exchanger for this purpose, which comprises series of metal sheets forming the flow spaces for the heat transmitting fluid from the turbine and the heat absorbing fluid from the compressor. To increase the heat transfer between these fluids, they are passed through the flow spaces in mutually opposite directions. As will fully appear from the following detailed description of the structure of the heat exchanger, this counterfiow is provided by two series of passages for the heat transmitting and heat absorbing fluids respectively. By the peculiar form 01 the sheets, the passages of one of these series, for the heat absorbing fluid which is under higher pressure from the compressor, are formed by the spaces enclosed by the sheets, and the passages of the other series, for the heat transmitting fluid which is under lower pressure from the turbine, are formed by the spaces between sheets. These latter passages are closed along the sides of the sheets by liner bands which are provided with series of gaps or interruptions. The advantage of these gaps is that they reduce or eliminate the loss of heat caused by conduction by the liner bands from the hotter end to the cooler end of the heat exchanger. Suitable means are provided for entry and exit ports i'orthe passages, to provide the eounterilow-oi' the fluids.

In the drawing: I

Fig. 1 is a horizontal section or the heat exchanger illustrating the directions of flow oi the cotmtercurrents of the heat absorbing and the heat transmitting fluids.

Fig. 2 is an enlarged perspective view of a seriesof sheets, the sheets being broken away to show their relation to io'rmthe alternate passagestor Pig. 8 is a fragmentary side elevation oi'the series 01' sheets shown in Pig. 2.

mulls:

transverse vertical section through alerlocoitheshoets. 1

E at the right of I sage M is closed at portion B--3.

disposed the substantially hexagonal sheets arranged in a series to form the passages for the fluids. For purpose oi illustration, there are shown in Fig. 2 three sheets A, B and C. All the sheets are formed with parallel sides S andconverging ends E with a tongue Textending outwardly from each end. The sheet A has two down-pressed ribs A-i symmetrically disposed on either side of the longitudinal axis, parallel to the sides S and with end portions reversely turned toward the edges of the converging ends E of the sheet. The sheet B has a peripheral flange 3-4, a peripheral shoulder 3-2 and a raised The sheet B has an upwardlypressed rib, B-4 disposed on the longitudinal axis with end portions reversely turned toward the edges of the converging ends E of the sheet. The sheet C is identical with the sheet A.. As illustrated in Fig. 2, sheet B is placed upon sheet A and sheet C is placed upon sheet B. By reason or the shoulder B-I forming the raised portion 18-3 of the plate B, there is provided the Dessage M between sheets A and B, and by reason -01 the rib 3-4 of sheet B and menses-I or sheetC, spacing apart the C (Fig. 4)..

the sheets B and C resting upon continuity of the bands L inbeiore explained. i a

In order to provide for the oounterflow of the fluids through the passages M and N r'espectivelm; it is necessary to provide the passages with inlet" and outlet ports at their respective ends, and these will now bedescribed. As clearly illustrated in Fig. 2, the pass M has an entry Port P--l at the near edge of the end E at the left oi the-figure, which is provided by interrupting the flange B-.l and shoulder 3-2 of the sheet B, the exit port P--2 for passage M being providedby a similar arrangement on the tar edge of the end'E at the right of the figure. Since the flange B are not interrupted at the near edge of the end the figure and correspondingly, or the end Eat the left, the pasthose portions.

Directly above the entry sage N. there is provided a suitable closure block 0 between the sheets B and C to close the posat the far edge sheets B and C, ther'i; is formed the passage N between the sheets 13 and} 3-] and shoulder B -Z of sheet port P-l of the 3293- sage N, suitable packing O-l such as solder being provided at the outer ends of block between it and the flange B-l of sheet B and the adjacent liner band L. A similar closure 0' is provided above the exit port P--2'. Since the closures O and O' are applied to the passage N only at these portions directly above the ports P-i and P-Z, the passages N have entry and exit p0rtsP3 and P-fl respectively directly above the closed end portions of the passages M.

As illustrated in Fig. 1, the assembled sheets A, B and C haveapplied thereto, at each end of the assembly, a casing 2 having a wall 2-a applied to one side of the tongues T of the sheets A, B

and C and another wall 2-47 extending to and applied against the ends of the liner bandsL, to communicate with the ports P-- i and P-2 respectively, of the passages M. The relation of the assembled sheets A, B and C and the casings 2 is such that only the passages M communicate with the casings 2 and the passages N are so closed as not to communicate with the casings 2.

An entry pipe 3 passed through the wall l connects with one casing 2 and an exit pipe 4 passed through the wall 9 connects with the other casing. The pipes 23 and #3 supply the heat absorbing fluid to the passages M, through their entry and exit ports P-i and P--2.

Anentry pipe 5 passes through the wall t adjacent the pipe 6 and an exit pipe 6 passes through the wall 8 adjacent the pipe 8. The pipes 5 and 6, communicating with the interior of the heat exchanger, supply the heat transmitting fluid to the passages N through their entry and exit ports P-8 and P-d.

What is claimed is:

1. A heat exchanger for high pressure fluids comprising a plurality of substantially parallel spaced sheets of a general hexagonal shape, means to close the peripheries of said sheets to form spaces therebetween for passage of heat exchange fluid, said means being interrupted alternately at each of the four edges of the hexagonal sheets in opposed longitudinal relation to form entry and exit ports for alternate spaces between the sheets, said means including hands between the margins of pairs of said sheets and extending longitudinally of said sheets, said longitudinally extending bands being interrupted at intervals to decrease heat transfer from one end to the other, thereof.

2. A heat exchanger for high pressure fluids comprising a plurality of substantially parallel spaced sheets of a general hexagonal shape, means to close the peripheries of said sheets to form spaces therebetween for passage of heat exchange fluid, said means being interrupted alternately at each of the four edges of the hexag onal sheets in opposed longitudinal relation to form entry and exit ports for alternate spaces between the sheets, said means including bands be=- tween the margins of pairs of said sheets and extending longitudinally of said sheets and in parallelism to the path oi flow of said heat exchange fluid, said longitudinally extending bands being interrupted at intervals toclecrease heat transfer from one end to the other thereof.

GEORGE JENDRASSIK.

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