US2224787A

US2224787A - Heat exchanger

Info

Publication number: US2224787A
Application number: US269353A
Authority: US
Inventors: Horney Fred
Original assignee: Ljungstroms Angturbin AB
Current assignee: Ljungstroms Angturbin AB
Priority date: 1938-04-14
Filing date: 1939-04-22
Publication date: 1940-12-10
Anticipated expiration: 1957-12-10
Also published as: GB527452A; FR840298A; DE758672C

Description

Dec. 10, 1940. F. HORYNEY I 2,224,787

HEAT EXCHANGER Filed April 22, 1939 2 Sheets-Sheet l Dec. 10, 1940. F; HORNEY HEAT EXCHANGER Filed.April 22, 1939 2 Sheets-Sheet 2 Patented Dec. 10 1940 HEAT EXCHANGER Fred Horney, Stockholm, Sweden, assignor to tiebolaget Ljungstriims Angturbin, Stockholm, Sweden, a corporation of Sweden Application April 22, 1939, Serial No. 269,353 In Germany April 13, 1938 Claims. (01. 257-6) This invention relates to a regenerative beatexchanger having a rotor rotatable within a hous ing and supporting the regenerative material which is traversed in radial direction by the heat- 5 exchanging media with the axis of the rotor preferably arranged vertically. According to the present invention one, preferably the upper, face of the rotor is closed while the inlets and outlets for the heat-exchanging media are arranged so that one medium enters in a radial direction and flows out in an axial direction whilst the other medium enters in an axial direction and flows out in a radial direction.

A regenerative heat-exchanger thus constructed is advantageous in several respects. For ex ample, the preferably vertical rotor axis, especially when the upper face of the rotor is closed, may be supported and driven in a very simple manner. Due to the fact that the temperature of the heat-exchanging media at both ends is substantially the same and increases or decreases uniformly towards the centre, the rotor has no tendency to warp which in view of the several packing elements necessary is of great advantage. As the rotor is submitted to only unimportant heat stresses, in the case where small amounts of the media exchange heat or where only a small heat-exchange out-put is desired not only can the axial and radial dimensions of the heat-exchanging mass be kept small but also the dimensions of the interior rotor may be small which with rotary heat-exchangers of known construction is not always immediately possible 35 in view of the heat stresses set up therein.

This construction of heat-exchanger also allows a simple adjustment of the housing relative to the rotor thus enabling the packing between the said members at the periphery of the rotor and at its fiat face to be adjusted exactly. The heat exchanger according to the invention may be simply constructed with the heat-exchanging material arranged in compartments disposed along the rotor periphery which are readily exchangeable, for example for the purpose of cleaning the filling mass, without the necessity of removing any conduits or parts of the rotor andhousing. The'individual compartments may be removed from the rotor without special means. 50 such as rails and guides and'can also be readily re-inserted in position.

A heat-exchanger constructed in the above mentioned manner has also the advantage that the heat transferring plates comprising the re- 55 generative filling mass may all be of the same dimensions which simplifies their construction and reduces their cost.

The invention will be hereinafter more fully described-with reference to the accompanying drawings showing a regenerative heat-exchanger constructed according to the invention and intended for pre-heating the combustion air of steam boiler furnaces and in which:

Fig. 1 is a central longitudinal section through the heat-exchanger shown diagrammatically; 10

Fig. 2 is a plan-viewof the heat-exchanger;

Fig. 3 is a section through half the 'rotor with its respective housing members, on a larger scale;

Fig. 3a is a detail onlarger scale of a portion of the structure shownin Fig. 3; 1

Fig. 4 is a plan-view of a part of the rotor;

Fig. 5 is a perspective view-of one of the exchangeable compartments of the rotor;

Fig. 6 shows a detail.-

Referring to the drawings a preferably vertical impeller shaft 2 is supported in an axial and radial thrust bearing 4 and is set in rotation by means of an electric motor 6 with intermediate transmission 8. The driving unit and the rotor rest on a supporting structure I0, l2 which is supported at M and I6. On a cylindrical hub l8 of the rotor axis are welded radial partitions 20 which sub-divide the rotor into a number of sectors. The partitions 20 are inter-connected at their periphery by being welded to

rings

22 and 24 and are covered over at their upper edges by a plate 26. This plate, however, does not extend radially to the peripheral edges of the partitions,

but leaves an annular part open through which compartments containing the heat-exchanging mass can be removed or inserted. On its upper face the casing is closed by aplate 28. The plate 28 has an opening 32 closable by acover 30 which corresponds substantially to the dimensions of aa compartment and through which the individual compartments of the series can be removed or inserted. Each compartment containing the heat-exchanging mass consists of an upper part sectorshaped plate 34 and a similarly formed base plate 36 together with two

side walls

38 and 4 0. By means of somewhat shorter intermediate panels 42, M and 46 each compartment is sub-divided into four divisions in which the heat-exchange mass is arranged in the manner shown in Fig. 5. For the sake of clearness in this figure only the space existing between

thewalls

40 and 42 is filled with heat-exchanging material which consists of radially arranged vertical plates 48, 50 (if known type. I

As can be seen from Fig.-3 the base plate 38 is shorter than the

plates

40, 50 thus providing a ready downward discharge for the medium flowing through theplates. The

plates

34 and 38 are welded to the lateral walls 38'and 40 so as to form a unit containing the heat-exchange plates which-can be lifted out of the rotor by means of a handle 52 which is secured to' the plate 34. When the compartment is inserted in the rotor its upper plate 34 rests in the manner shown in Fig. 3 partly on the ring 22 and partly on the -cover plate 26 and the compartment can, therefore, expand freely downwardly. The extent of movement of the compartments and of the plates inserted therein is limited outwardly by the rings 22 and 24' and inwardly by

rings

54 and 56 which are welded to the partitions 20.

The joints formed on the upper face between adjacent compartments are closed by small plates 58, (it which each overlap two compartments but are connected with only one compartment so as to allow the separate removal or insertion of the compartments.

Another form of packing is shown in Fig. 6 wherein the upper plates 34' and 34" of two adjacent compartments are provided with

lateral strips

62 and 64 respectively which overlap in the manner illustrated and render the compartments mutually air tight.

- The housing of the heat-exchanger is also suspended on the supports It, i2.- A T-shaped ring 66 is connected with these supports and carries through an. adjustable connection a U-shaped ring 68, which is connected-to the housing. The adjustable connection consists in the present embodiment of an eccentric or cam shaft 10 which is supported in the T-ring and supports the U- ring and by the rotation of which the U-ring together with the entire housing can be raised or lowered relatively to the supports l0, l2 and, therefore, also relatively to the rotor.

A T-shaped ring 12 is connected with the U- ring 68 by means of a number of vertical tubes 14. A cover plate, 16 provided with openings for the passage of the heat-exchanging media is welded to-the- T-ring I2 and carries connecting

members

18 and 80 located on the undersurface of the rotor and comprising channel-

irons

82, 84,

86, 88 or 90, 92, 94 and 96 respectively. These 59 connecting supports are not rigidly connected 6o fiangeof member 82.

with the plate 16 but are connected-by any suitable means permitting longitudinal expansion of the connecting supports relative to the cover plate to avoid deformation of these members as a result 55 of differential expansion due to temperature changes. One such arrangement is indicated in Fig. 3a wherein a bolt TI is shown welded to the lower face of plate'lS, this bolt passing through an elongated opening or slot 83 in the upper In order to permit sliding movement between the contacting members while at the .same time maintaining them in close contact so as to prevent leakage, the parts are held in proper relation by means of a spring 85 com- 5 pressed between suitable retaining washers located between flange 83 and nut 8.1.

' The radial connecting sockets for the heat-exchanging media are denoted by 98 and I00 and together with suitable light sheet, metal struc- 70 ture secured thereto form a housing I02 of the pre-heater. v

The various packing devices for the heat-exchanger-are constructed as follows. At the upper periphery of the rotor packing relatively to 75 the housing 'iseflected by means of an annular justable and together with the packing strips I08 prevent intermixing of the air and gas. The radial partitions are also provided along their lower edges with packing plates I M which slide against the cover-plate 16. Finally a packing strip H6 connected with the hub of the rotor is constructed of annular shape and also slides against the cover-plate 18.

The boiler waste gases pass through the socket 98 into the air pre-heater, flow in the direction of the arrows H8 in a radial direction through the heat-transferring plates and leavethe air-preheater through the outlet socket 18. The air to be pre-heated flows in an axial direction through the socket 94 and passes through the heat-transferring plates in a radial direction in the direction of the arrow I20. As will be seen the heatexchange is effected in counter-flow.

As will be seen from the-drawings the driving device for the rotor is arranged completely outside the channels and conduits for the heat-exchanging media, this construction difiering advantageously from prior proposals wherein the driving device is arranged in the interior of the rotor. I The compartments containing the heat-transferring plates in the illustrated embodiment are in the radial cross-section a part-sector shape with the side walls 38' and 40 arranged radially. Obviously when using

corrugated plates

48, 50 the depth of the corrugations should be reduced towards the centre of the rotor. However, the

walls

38, 40 may also be arranged so as to lie parallel to one another in which case the depth of the corrugations of the-plates may be uniform throughout their entire breadth. In this arrangement there would result between adjacent compartments empty wedge-shaped spaces, but this construction has the advantage that the plates may be constructed more simply and that they can be utilised for rotors of different radi dimensions.

What; claim is:

1. A regenerative heat exchanger comprising a stationary casing, a rotor mounted to rotate about a vertical axis in said casing, regenerative heat exchange mass carriedby said rotor and providing passages extending in generally radial direction therethrough, means providing a closure for one end of said rotor, openings arranged in the means between said rotor and said casing struc- .ture for establishing separate'paths of flow for different 'fluid media through said openings and said passagesfone of said paths of flow providing 'for axial admission to and radial exhaust from said exchanger of one fluid media and the other of said passages providing for radial admission and axial exhaust from said exchanger 09a second fluid media, and means for moving said rotor and easing structure axially relative to each other to adjust" said sealing means.

- '2. A regenerative heat exchanger comprising a supporting structure, a rotor rotatably suspended assets? from said supporting structure, acasing structure surrounding said rotor, said rotor being closed at its upper end and carrying regenerative heat exchange mass providing passages extending radially therethrough, said casing structure having openings in its side walls and in its lower end communicating with said passages, sealing means between said rotor and said casing structure providing separate paths of now for difierent fluid media through said openings .and passages, and meansv for suspending said casing structure from said supporting structure, said means being adjustable to move the casing structure axially relative to the rotor whereby to adjust said sealing means.

3. In a regenerative heat exchanger of the character described, a rotor mounted to rotate about a vertical axis, said rotor comprising a plurality of radially extending partitions providing sector-like spaces therebetween, a closure plate atthe upper end of the rotor for closing said spaces, the radially outer portion of said closure plate having openings therein and means for removabiy suspending regenerative heat exchange mass from the upper portion of the rotor, whereby to permit said mass to expand and contract freely in axial direction from its place of suspension, said means extending through said. openings and includingparts forming closures for said openings when said means is in place, whereby to effect closure of the entire end of the rotor.

4. In a regenerative heat exchanger, a casing structure including two rigid annular members axially spaced apart, a series of peripherally spaced axially extending spacing elements rigidly connecting said annular members, a rotor having a series of radially extending partitions and an end closure structure at one end thereof, said rotor having regenerative mass between said partitions providing passages for flow of heat exchange media therethrough in generally radial direction and being mounted to rotate within said casing structuregannular sealing means between a first one of said annular members and said end closure structure, a casing end plate secured to the second one of said annular members and providing therewith a casing end structure, said end plate having openings therein communicating with radially inner portions of the passages in said regenerative mass, annular sealing means between the rotor and said casing end structure radially outside said-openings, andannular sealing means between the rotor and said casing end structure radially inside said openings.

5. In a regenerative heat exchanger, a' casing structure including two rigid annular members axially spaced apart, a series of peripherally spaced axially extending spacing elements rigidly connecting said annular members, a rotor having a series of radially extending partitions and an end closure structure at one end thereof, said rotor having regenerative mass between said partitions providing passages for flow of heat exchange media therethrough in generally radial direction and being mounted to rotate within said casing structure, annular sealing means between a first one of said annular members and said end closure structure, a casing end plate secured to the second one of said annular members and providing therewith a casing end structure, said end plate having openings therein communicating with radially inner portions of the passages in said regenerative mass, annular sealing means between the rotor and said casing end structure radially outside said openings, annular sealing means between the rotor and said casing end structure radially inside said openings, axially extending wall members carried by said casing structure, said wall members being spaced apart circumferentially of said structure and having concave faces concentric about the axis of the rotor, and sealing means carried by the axially extending'outer edges of the radial partitions'oi the rotor, the last mentioned sealing means being adapted to provide a seal between each partition and the respective faces as the partition passes said faces.

FRED HORNEY.