US3373798A - Regenerator matrix - Google Patents

Description

March 19, 1968 E; R. BRUMMr-:TT 3,373,798

REGENERATOR MATRIXl I N VEN TOR.

TTORNEY -H '-'t'g l Y Car/ rzzmW/eff v United States Patent liice 3,373,798 Patented Mar. 19, 1968 3,373,798 REGENERATOR MATRIX Earl R. Brummett, Indianapolis, Ind., assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Nov. 19, 1965, Ser. No. 508,711 16 Claims. (Cl. 165-10) ABSTRACT F THE DISCLOSURE A radial-flow rotary regenerator matrix has a core made by coiling edgewse one or more strips having more or less arcuate extent, having a finely corrugated surface to space the sheet to allow liuid iiow, and having radial corrugations which taper so as to effectuate the curvature of the strip 'and interfit to block fluid ow circumferentially of the matrix.

My invention is directed to an improved matrix structure for radial flow regenerators. Such a matrix is a porous drum which is rotated slowly through two streams of gas at different temperatures so as to absorb heat from one stream and `deliver the heat to the other. The principal object of my invention i-s to provide a matrix having a smooth surface and thus superior sealing against leakage and also a structure which is much more practicable to assemble and much more stable dimensionally than m-atrix structures commonly used.

To outline brieiiy the nature of my matrix, it has a core which may be made up by coiling edgewise one or more strips having a finely corrugated or otherwise relieved surface and having radial corrugations which tapers so as to effect the curvature of the strip and which also serve to block ow circumferentially of the matrix. The matrix also normally includes a rim at each end of the core and tie bolts extending 'between the rims to hold the rims and core assembled. The nature of the invention will be more clearly apparent from the detailed description of preferred embodiments of the invention and the accompanying drawings thereof. v

FIGURE 1 is an axonometric view of a radial flow regenerator matrix; FIGURE 2 is a partial transverse section of the same taken on the plane indicated in FIGURE l; FIGURE 3 is Ian end elevation with parts cut Way and in section; FIGURE 4 is an exploded view of the same; FIGURE 5 is a perspective view showing a portion of FIGURE 4 to a larger scale; FIGURE 6- is a fragmentary view of the outer surface; FIGURE 7 is a fragmentary view of the inner surface; FIGURE 8 is a view corresponding to FIGURE 5 showing a modification of the core material; and FIGURE 9 is a similar view of a fur-ther modification.

The general form of a matrix of the sort to which my invention is directed is illustrated in FIGURE 1. It is a drum or hollow cylinder comprising annular end rings or rims 9 and 10 and a porous core cylinder 11 between the rims. According to my invention, the core is made up of a coil or the equivalent of corrugated thin heat resisting metal. Bolts 13 extending from one rim to the other hold the parts rigidly assembled. It is important that the matrix structure have a high heat capacity and accept and reject heat rapidly, that it have Aa minimum resistance to gas tiow through it to reduce energy losses, and that it veffectively prevent gas iiow circumferentially of the matrix because such flow would represent undesirable leakage from a higher pressure fiuid to a lower pressure. While numerous structures to attain this end have been devised, so far as I am aware there has been none in which the core of the matrix is a helical coil or stack of annular sheets of thin sheet metal. It may be mentioned at this time that the term coil as used herein may refer to a coil made up of a single strip, that is, having only one start; or it may be made up of two or more strips laid simultaneously into the coil, that is, a coil having more than one start. Also, a stack of ring-shaped or arcuate sheets of matrix material is functionally equivalent to a true coil and may lbe substituted for it.

In the embodiment of the invention illustrated in FIG- URES 3 to 7, the coil which denes the matrix core is made of two interleaved coils of curved corrugated strips which -are indicated in FIGURE 5 as coils or strips 17 and 18. The two strips preferably have small scale zigzag corrugations as indicated lat 19 in FIGURES 6 and 7, the zigzag nature of the corrugations being apparent from FIGURES 3 and 5. These zigzag configurations may be generally of the sort described in United States Patent No. 3,183,963 of J. R. Mondt. However, the corrugated sheet material is disposed in an entirely different way in the patent to form the matrix. The strips 17 and 18 of my invention may be made from a continuous strip of finely corrugated sheet metal preferably about one and one-half mils in thickness by further corrugating the strip. Thus, the strips 17 and 18 have major corrugations 21 which, as will be most clearly apparent from FIGURES 6 and 7, are much deeper at the inner periphery of the matrix than at the outer. These corrugations taper so that they telescope within each other as shown in FIGURES 6 and 7 to allow the corrugations 19 to make Contact. Since the corrugations 19 of the two strips are reversely disposed with respect to corrugations 21, the peaks of the corrugations 19 engage at several points between the inner and outer margins of the drum. Also, since the corrugations cross each other at an angle they do not prevent iiow circumferentially of the matrix. However, the corrugations 21 do engage sufficiently closely to prevent liuid flow circumferentially of the matrix past these corrugations. Corrugations 21 also firmly lock or spline the successive layers of the lcore together.

The greater depth of the corrugations 21 toward the inside of the matrix takes up sufficient material to cause `the strip -to curve with a diameter equal to that desired in the finished matrix. Thus the strips 17 and 18 readily fal-l into a suitable coil. The rims 9 and 10 are generally of rectangular cross section but are provided with grooves lor teeth on their inner or facing surfaces to cooperate with the major corrugations of the matrix. Thus, rim 10 is provided with a number of radial-ly extending teeth 23 which, like the corrugations 21, increase in height toward the inside of the matrix. The number of these teeth is not critical but there may be about lone hundred distributed evenly around the circumference. Similarly, rim 9 has teeth 2'5 which define grooves between them to receive the corrugations 21 which project toward this In FIGURE 2, in the central part of the ligure the section is taken through tthe zigzag corrugations 19, .whereas towards the rims the section is taken through the radial corrugations 21 which appear straight.

yIt may he pointed out that the primary reason for using a two-start coil is that it is simpler to make the strips this way, since the strip 18 may be identical to strip 17 except that it is turned over before 'the major corrugations 21 are formed in it. The major corrugations do not necessarily all extend from the sa-me face of the strip as illustrated in FIGURES 4 to 7. It may be preferred in lsome cases to have them extend alternately in opposite directions as illustrated by the strip 20 shown in lFIGURE l8 in which corrugations 2-1 extend from the .forward face of the strip and corrugations 211" extend from the rearward face. The zigzag corrugations '19 remain the ysame as in strips "'17 and 18.

Also, it is possible, although not considered very feasi- 3 ble, to provide a single strip such as in FIGURE 9 in which the direction of the zigzag of the minor corrugations 19 is reversed periodically in the strip. For example, the corrugations 19 could be of right hand for one complete circumference of the core and then of left hand, and so on. Or, they could reverse at shorter intervals so long as the arrangement is such that left-hand and righthand corrugations 19 alternate axially of the core when the material is stacked. With the directions of the corrugations thus reversing periodically, a single strip may be used. lt will also be understood that various other vcombinations are possible; as, for example, two strips may be used with minor corrugations such as 19 on one and none on the other strip. Various sorts of bumps, projections, or ridges may be provided. iHowever, the simple zigzag corrugation illustrated and described is preferred.

To make the complete matrix once the strip or strips are available, it is necessary only to coil or stack these upon one rim to a depth slightly greater than the desired width of the material, put the other rim in place, then connect the two rims, and then finish the surfaces of the cylinder 11. The rims are connected by the tie bolts 13 which have hexagonal socket heads 33. These heads seat in counterbores 34 in rim 9. The other ends of the bolts kare threaded and are received in threaded holes 35 in rim 10. The number of bolts is not critical but about twelve seems desirable. Each bolt 13 is enclosed in a cylindrical sleeve 37 which extends from one rim to the other and provides a strut between the rims. Preferably, the sleeves lit closely in holes 39 in the coil of strip but are somewhat loose on the bolts 13.

The holes 39 may be punched during the preparation of the strip or may be drilled or otherwise machined after the core has been assembled. The sleeves 37 engage both rims and limit the compression of the core by the bolts 13. When the bolts have been tightened, a hole is drilled from within the socket in the bolt head radially into the ring 9 and a small locking pin 41 is pressed into place and staked so that it will be retained.

After the assembly is thus completed, the inner and outer surfaces of the matrix are machined to a smooth accurate cylinder by electrolytic grinding. The result is `a smooth surface on which sliding contact seals may be used to prevent substantially all leakage between the two streams of gas when the matrix is put in service.

The previous description has been directed primarily to forming the core of one or more long or more or less continuous curved strips stacked in a helical or coiled formation. Clearly, however, the core may be made up of a stack of individual annular or arcuate sheets which are not helical or coiled in the usual sense of the term. For example, the sheets 17 and 18 as illustrated in FIG- URES 5, 6, and 7 may be only sutiiciently long to extend through one circumference of the core, in which case each successive layer of the core is a separate annular strip of metal. Moreover, the layers or elements of the core need not extend through an entire circle. For example, 180 or 120 arcuate segments may be used with the joints between the segments in successive layers relatively staggered. In this last case, the corrugations or splines are not necessarily tapered, as an arcuate blank could be used. Manufacture of the core material in a long strip is, however, more practical.

In the succeeding claims, reference to an element of the core is intended to refer to a layer whether or not the layer is strictly annular or whether it is a section of a coil or a sector of an annulus.

It will be clear to those skilled in the art from the foregoing that an extremely simple and easily assembled matrix structure results from the invention. Also, the coaction of the splines or corrugations on the rims and the elements of the matrix provide an extremely strong and rigid structure with most desirable characteristics for use as a radial flow matrix. A smooth external surface is readily attained to improve sealing.

The detailed description of preferred embodiments of the invention for the purpose of explaining the principles thereof is not to be considered as limiting or restricting the invention, as many modifications may be made by the exercise of skillA in the art.

I claim:

1. A radial-flow rotary regenerator matrix comprising a hollow cylindrical core of heat-transfer material pervious to flow of fluid radially through the core,

the core comprising a stack of arcuate sheet metal elements each lying substantially in a plane normal to the axis of the core,

at least some of the elements having surface relief creating liow passages between adjacent elements when disposed in the core,

the elements having generally radial corrugations extending across the elements from outer to inner edge distributed circumferentially around the core and interengaging telescopically when the elements are disposed in the core so as to spline the elements together and to inhibit fluid liow circumferentially of the core.

2. A matrix as recited in claim 1, the said corrugations tapering from the edge at the interior of the core to the edge at the exterior of the core and thus establishing a curvature of the element corresponding to the curvature of the core.

3. A matrix as recited in claim 2 including also two annular rims, one disposed at each end of the core, engaging the core.

4. A matrix as recited in claim 3, the rims having splined inner faces interlocking with the radial corrugations on the core.

5. A matrix as recited in claim 4 including also tie means extending through the core and into the rims holding the matrix assembled.

6. A matrix as recited in claim 1 in which the said elements are disposed in at least one helical coil.

7. A matrix as recited in claimA 2 in which the said elements are disposed in at least one helical coil.

S. A matrix as recited in claim 1 in which the surface relief is established by zigzag corrugations on the elements of reverse zigzag direction on elements alternating axially of the co-re.

9. A matrix for a radial-flow regenerator comprising a hollow cylinder defined by a helical coil of thin metal strip, the coil having one or more starts and a multiplicity of turns,

the strip being disposed edgewise with respect to the axis of the cylinder,

the strip having a configuration delining protrusions on at least one face thereof engaging an adjacent turn to separate the turns so that when the strip is coiled the resulting cylinder is pervious to flow of fluid radially through the cylinder.

10. A matrix as recited i1 claim 9, the strip having corrugations extending across the strip tapering from the edge at the interior of the cylinder to the edge at the ex terior of the cylinder and thus establishing a curvature of the strip corresponding to the curvature of the cylinder.

11. A matrix as recited in claim 10, the corrugations of adjacent turns of the strip being nested and in contact when the strip is coiled so as to provide a barrier at the corrugations to liow of fluid circumferentially of the cylinder.

12. A matrix as recited in claim 1li including also an end ring at each end of the cylinder, the rings engaging the ends of the coil and having radial teeth fitting the corrugations of the end turns of the coil.

13. A radial-How rotary regenerator matrix comprising a hollow cylindrical core of heat-transfer material pervious to flow of fluid radially through the core,

the core comprising a stack of arcuate sheet metal elements each lying substantially in a plane normal to the axis ofthe core,

at least alternate ones o-f the elements having a form providing surface relief of relatively minor magnitude engaging adjacent elements to provide space for flow of uid radially of the matrix between the elements, all of the elements having corrugations of major magnitude relative to the said surface relief distributed circumferentially around the core, the corrugations extending radially of the core from inner to outer surface of the matrix and interengaging telescopically into contact with the corrugations of adjacent elements so as to spline the elements together and to inhibit fluid flow circum-ferentially of the core. 14. A matrix as recited in claim 13 in which the said corrugations taper from the interior to the exterior of the core to compensate for the greater circumference of the element at the exterior than at the interior of the core. 15. A matrix fas recited in claim 14 in which at least some of the elements are helices of more than one turn. 16. A matrix as recited in claim 13 including also two annular rims, one disposed at each end of the core, the rims having splined inner faces interlocking with the said corrugations.

References Cited UNITED STATES PATENTS ROBERT A. OLEARY, Primary Examiner.

T. W. STREULE, Assistant Examiner.

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