EP2023070A1 - Regenerative heat exchanger and radial seal for use for such and method for separating gaseous media in a regenerative heat exchanger - Google Patents

Abstract

The heat exchanger has a rotor (10) comprising a set of radially running sector walls (12). Heat accumulator chambers (19) are arranged one behind the other in a radial direction of the rotor and through-flowable by a gaseous medium. The chambers comprise openings formed in an area of front surfaces of the rotor, and a radial seal (20) is arranged at the front surfaces of the rotor, where the seal and the rotor are rotatable relative to each other. The radial seal is designed in such a manner that the seal partially covers the opening during the operation of the heat exchanger. An independent claim is also included for a method for separating gaseous medium in a regenerative-heat exchanger.

Description

The invention relates to a regenerative heat exchanger according to the preamble of claim 1 and a radial seal for use in a regenerative heat exchanger according to the preamble of claim 8. Furthermore, the invention relates to a method for separating gaseous media in a regenerative heat exchanger according to the preamble of Claim 11.

In known heat exchangers of this type, a normally cylindrical heat storage body is provided, which is designed for the flow of gaseous media. These heat storage bodies are divided into sectors by radially extending walls, hereinafter called sector walls. The sector walls extend substantially continuously from the longitudinal axis of the heat storage body to the heat storage edge and are aligned parallel to the longitudinal axis or lie in a plane therewith. Also, the sector walls are formed continuously from one heat storage end face to the other. For design and cost reasons, the sector walls are usually evenly distributed in the heat storage body, so that result in sectors of the same shape and the same volume. Since the heat storage body partially have diameters of 20 m and more, the sectors are subdivided for construction reasons by the introduction of additional walls in several, permeable by gaseous media heat storage chambers, often a plurality of heat storage chambers within a sector in heat storage body radial direction are arranged one behind the other.

In principle, recuperative or regenerative heat exchanger systems are available for the exchange of heat between gaseous media. In the recuperative heat exchangers, the flow of the heat-emitting medium is applied directly to one or more streams of heat-absorbing media and the heat is transferred directly through a partition wall. When regenerators is transfer the heat by means of a heat-storing intermediate medium. Such heat-storing intermediate media are arranged in regenerative heat exchangers in the heat storage chambers of the heat storage body. These are often layered sheet steel layers, which can be enamelled if necessary. These are often designed as basket systems, which can then be used as a whole in a heat storage chamber and fill them. Alternatively, some ceramic bodies or heating surfaces made of plastic are used as heat-storing intermediate media.

In the known heat exchangers, the heat storage body is either fixed or rotatable about its longitudinal axis, wherein in the former case of a "stator" and in the latter case of a "rotor" speaks. In a heat exchanger having a rotor, the rotor housing, including the gas duct connections attached thereto, is fixed, so that the rotor rotates through the different gas flows. In contrast, in a heat exchanger with a stator on both sides of the stator rotating gas duct connections, so-called rotary hoods are arranged. In both variants, therefore, the various areas of the heat storage body alternately flows through all the existing gas flows.

The heat-emitting gaseous medium flows through the heat storage body from one end face to the other and thereby heats the heating elements arranged therein in the individual heat storage chambers, which store this heat. Further, one or more heat-receiving gaseous media flow through the heat storage body, also from one end face to the other. By the rotation of the rotor or the rotary hoods, the heated heating elements are flowed through by the cold gas streams and thus heat them.

In the power plant area, for example, a hot, heat-emitting exhaust gas flow and a cold, heat-absorbing air flow are often passed through the heat storage body. This is the process of air preheating (Luvos). Subsequently, the heated air is supplied to a furnace and accordingly referred to as combustion air or combustion air. The increased heat of combustion air by the heat exchanger substituted parts of the energy contained in the fuel, whereby the amount of fuel required for the firing is reduced. Consequently, the amount of CO ₂ released during firing is also reduced.

Furthermore, the described heat exchangers can also be used for gas preheating (Gavos). In heat exchangers which are designed as so-called DeSOx systems, for example, a hot raw gas is cooled with a high SOx content and heated a clean gas with low SOx content. In so-called DeNOx plants, in turn, a hot clean gas with a low NOx content is cooled and a crude gas is heated with a high NOx content.

Usually, the heat-emitting gas stream and the one or more heat-absorbing gas streams according to the countercurrent principle are conducted opposite one another through the heat storage body. Thus, on the side where the heat-emitting gas is introduced into the heat storage body, the heat-absorbing gas is led out of the heat storage body. This is called the hot side of the heat exchanger. On the opposite side, the cooled, heat-emitting gas is blown out and the still cool heat-absorbing gas is blown. Accordingly, this is the so-called cold side. In the case of a regenerative heat exchanger which is designed, for example, for air preheating, it therefore has a gas inlet and an air outlet on its hot side and a gas outlet and an air inlet on its cold side. The exhaust gas thus flows through an exhaust gas region which extends from the hot to the cold side of the heat exchanger, while the combustion air flows through a combustion air region which extends from the cold to the hot side.

The division of the heat storage body into heat storage chambers is provided to prevent the various gas streams from mixing with each other. Through the various chambers, separated from each other, simultaneously heat-emitting gas or heat-absorbing gas out. In order to ensure a flow through or around the heat storage intermediate chambers located in the heat storage chambers, the heat storage chambers are open at the end faces of the heat storage body.

To separate the different gas flows from one another, one or more radial seals are provided on the end faces of the heat storage body. A radial seal is often formed as a bar or bar and extends orthogonal to the axis of rotation or longitudinal axis of the heat storage body extending over the diameter of the heat storage body. In this case, it is usually flat and runs through the heat storage body center. It is often made of metal or other materials such as e.g. Made of plastic and may be formed in one piece or in several pieces.

The radial seal may be designed to be adjustable in the direction of the heat storage body longitudinal axis, that is to say away from the heat storage body or towards the heat storage body. Frequently, the radial seals are performed in this way to compensate for heat-induced deformation of the heat storage body can. Thus, the sealing gap between the radial seal and the heat storage body front side are kept as low as possible in order to reduce leakage between the different gas streams. The maintenance of a minimum sealing gap is necessary to ensure the rotatability of heat storage body and radial seal relative to each other.

Typically, the radial seal consists of two or more seal arms, with a seal arm extending substantially from the axis of rotation to the outer edge of the heat storage body. The number of seal arms usually depends on the number of different gas streams present. Flow, for example, in a heat exchanger that uses a rotor as a heat storage body, two gas streams through the rotor, two sealing arms are provided both on the cold and on the hot side, with three gas streams three sealing arms, etc. In that the radial seal relative is arranged stationary to the rotational movement of the rotor, the openings of the heat storage chambers rotate under the radial seal therethrough. In one complete revolution of the rotor, each point of the end faces of the rotor is once below or above each seal arm.

The radial seals have been formed in known regenerative heat exchangers so that in each rotational position, that is, any position of the heat storage body and radial seal to each other, a sector wall below and above a sealing arm. Thus, the various gas areas, for example, the combustion air area and the exhaust gas area, always separated by a radially extending from the axis of rotation to the heat storage body edge sector wall.

In order to further reduce the leakage between the various gas areas, regenerative heat exchangers have been presented in which the radial seals are formed, which are at least temporarily arranged during operation of the heat exchanger, two sector walls below or above a rotary arm. As a result, the sectors and thus also the heat storage chambers arranged therein are completely covered in each case once by the sealing arms in the case of a rotor circulation or in a rotary hood circulation. This should reduce the leakage and thus improve the efficiency of the heat exchanger. Such a heat exchanger is used for example in the DE 44 20 131 C2 presented, in which even at each rotational position, at least two adjacent sector walls are arranged below a sealing arm.

The continuous closing and opening of the heat storage chambers creates permanent, mechanical vibrations. These are caused by the different pressure conditions that occur when opening and closing the heat storage chambers and have a pulsating effect on the radial seals. This process is also referred to as "pumping" the seals. The intensity of this pumping and thus also the intensity of the action on the radial seal depends on the pressure differences between the different gas flows and on the area of the seals. As this process is repeated continuously, the mean sealing gap height increases. In addition, the wear of the radial seals and the end faces of the heat storage body is considerably increased. These factors result in an increase in leakage. Greater leakage is equivalent to a higher energy requirement for the drive of the fans, which are required for the transport of the flue gases or the air, which is reflected in a deterioration of the efficiency of the regenerative heat exchanger. In addition to this deterioration, higher leaks increase pollutant emissions, such as CO ₂ , NO _x , SO _2, and ashes that you want to keep as low as possible. Furthermore, in the leakage flow, which extends below the radial seal between the different gas areas, exhaust residues may be carried along, which can attack the radial sealing surfaces, whereby the tightness of the radial sealing strips is further deteriorated.

The invention is therefore based on the object to provide a regenerative heat exchanger, a radial seal for use in a regenerative heat exchanger and a method for separating gaseous media in a regenerative heat exchanger, by the pumping of the seals and thus the leakage between the various Gas areas and the wear on the radial seals and at the end faces of the heat storage body can be reduced.

The solution to this problem is achieved with the regenerative heat exchanger according to claim 1. Advantageous further developments are specified in the dependent claims.

The regenerative heat exchanger thus has a cylindrical heat storage body, which is divided by a plurality of radial sector walls into sectors, wherein in each sector at least two radially arranged in succession heat storage chambers are provided. The heat storage chambers are designed to flow through the gaseous media and accordingly have openings in the region of the end faces of the heat storage body. Furthermore, at least one radial seal is provided on an end face of the heat storage body, preferably on both end faces, which is designed as a covering surface for the heat storage chamber openings. The radial seal is designed so that it covers each heat storage chamber opening alternately completely upon rotation of the rotor or the rotary hoods. The openings of the heat storage chambers are constantly closed and reopened during operation, each opening is covered at least once from each radial seal at a complete rotor circulation or rotary hood circulation. Are the heat chambers continuous from one end face to the other formed, it is expedient to form and arrange the radial seals on the two end faces so that both openings of a chamber are closed and opened substantially simultaneously and thus this chamber is completed when appropriate rotational position. This is advantageously achieved in that the arranged on the two end faces, opposite radial seals are formed substantially uniform and congruent.

According to the invention, the radial seal is now designed such that it covers the opening of at least one of these heat storage chambers of the radially successively arranged heat storage chambers of a sector in each rotational position, that is, in any position of heat storage body and radial seal to each other at most partially. The basic idea of the invention is thus to arrange the opening surfaces of the heat storage chambers arranged one behind the other within a sector and the covering surface of the radial direction relative to one another such that never all radially consecutively arranged heat storage chambers of a sector at the same time and thus at no rotational angle position of the rotor or the rotary hood are covered by the radial seal. In principle, this relative arrangement can be achieved both by a corresponding design of the radial seal and by a corresponding design of the heat storage chamber geometries. For design and cost reasons, the geometries of the sector walls and the heat storage chambers are maintained and the fit becomes volatogenic in the radial seal. In principle, all geometries that produce the effect described above can be used for the radial seal.

In other words, the fact that there is only at most partial coverage in the at least one heat storage chamber of the heat storage chambers of a sector arranged radially one behind the other means that this heat storage chamber is not completely or not covered by the radial seal. In contrast to the previously known heat exchangers, therefore, not all the heat storage chambers of a sector arranged one behind the other are completely covered at the same time. The cover of this at least one chamber is thus separated in the invention temporally from the cover of the other chambers arranged one behind the other, while in certain rotor or rotary hood positions in the known from the prior art regenerative heat exchangers, all of these chambers are covered at the same time , This "temporal pulling apart" of the covering operations, the vibrations that are caused due to the different pressure conditions when opening and closing the heat storage chambers, significantly reduced. Thus, the interaction of the vibrations is reduced to the radial seals. A "pumping" of the seals is prevented or significantly reduced. This results in less wear and thus lower leakage and longer service life of the radial seals. Furthermore, the efficiency of the entire power plant concerned is improved.

The simultaneous coverage of all successively arranged heat storage chambers of a sector in the prior art results firstly from the fact that the sectors are formed from the rectilinear, radial sector walls and arranged therein heat storage chambers as well as the sectors evenly distributed in the heat storage body. This arrangement necessarily results from design and cost considerations. On the other hand, for the same reasons, the individual sealing arms of the radial seal have always been formed substantially linearly, in part with dovetail-like widenings in the region of the heat storage body edge. Only in the present invention has now been recognized that a change in the geometry of the radial seal which is designed with respect to the geometry of the heat storage chambers and the rotational speed of the rotor or the rotary hood, the desired effect, namely the reduction of the vibrations causes.

In order to further reduce the extent of the oscillations, it is preferable for more than one heat storage chamber of the heat storage chambers of a sector arranged radially one behind the other to be at least partially open in each rotary position. Thus, in a preferred embodiment, the radial seal is designed such that it completely covers at most one heat storage chamber of the heat storage chambers arranged one behind the other of a sector at any given time, that is, at each rotational angle position of the rotor or the rotary hoods. As a result, the interaction of the vibrations resulting from the closing and opening of a plurality of heat storage chambers is avoided and the pumping of the seals is further reduced.

In a further preferred embodiment, each radial seal comprises at least two sealing names. Of these at least two sealing arms of the radial seal, which extend substantially from the longitudinal axis radially outwardly to the heat storage body edge, at least one sealing arm is formed asymmetrically. This means that the geometry of the at least one sealing arm is shaped such that the surface of the sealing arm is not symmetrical in a plan view. This excludes both axis symmetry and point symmetry. It can therefore find no axis or no point around which the Dichtarmfläche can be mirrored. Such a design can be achieved particularly well a time-delayed coverage of the individual heat storage chambers.

In a further preferred embodiment, the individual sealing arms of the radial seal are subdivided into sealing arm segments. The individual segments are arranged one behind the other in the radial direction and close directly to each other, so that they assemble into a seal arm. The two outer edges of a segment are each formed substantially linear. Furthermore, in each case the outer edges of adjacent Dichtungsarmsegmente offset from each other and alternatively or additionally angled with respect to their adjacent outer edges. In each case, the outer edges are considered on the same seal arm side. By the offset of the outer edges against each other or the angled arrangement of the outer edges is avoided that all within a sector successively arranged heat storage chambers are simultaneously covered by a sealing arm.

Frequently, the heat storage bodies are formed so that they have a plurality of coaxial annular walls. These annular walls are often cylindrical and have the heat storage body longitudinal axis as a common axis. Thus, the annular walls cut through the individual sectors and divide them into subsectors in the radial direction. These subsectors may correspond to the dimensions of a heat storage chamber. However, it is also possible in principle to subdivide the subsectors further into several heat storage chambers. When a heat storage body is subdivided by such annular walls into subsectors, it is preferred that the individual seal arm segments of the seal arms be configured to extend radially across substantially one subsector or a plurality of adjacent subsectors. Corresponds to a subsector of a heat storage chamber, it is appropriate that over this subsector extending seal arm segment is formed to cover the chamber. It is thereby achieved that the edge offset between two sealing arm segments, or the point of intersection between two mutually angled outer edges of two adjacent sealing elements, is arranged substantially over a region against which two heat storage chambers or two subsectors abut one another. By means of this embodiment, the formation of the individual sealing arm segments can be better adapted to individual sub-sectors, so that the covering order of the individual sub-sectors or heat-storing chambers can be optimized during operation, whereby the oscillation volume is further reduced overall.

In a further preferred embodiment, at least one seal arm is divided into three seal arm segments, wherein the inner segment closest to the axis of rotation is cone-shaped. The cone-shaped inner segment is aligned so that it widens substantially in the radial direction. The adjoining middle segment tapers in the radial direction and preferably at least one edge of the middle segment is opposite to the one adjacent edge of the inner segment staggered in heat storage body circumferential direction. Due to the tapering of the middle segment in the radial direction, the edges of the middle segment are angled with respect to the inner cone-shaped outwardly widening segment. The cross-sectional area of the outer segment widens again in the radial direction and its edges are thus arranged angled relative to those of the middle segment. By calculations and tests on the part of the Applicant has been found that such a geometric design of a sealing arm when used with standard heat storage bodies is particularly advantageous and further minimizes the occurrence of vibrations.

In order to simplify the production of the radial seal and thus to produce and install this cost-effective, it is expedient to form all seal arms uniform. This is also expedient because the heat storage chambers are usually distributed uniformly in the heat storage body and thus optimal formation of a seal arm can be used for all seal arms.

It is further preferred that the radial seal is formed so that the inflow and outflow surfaces are substantially equal for the respective gaseous media. The inflow and outflow surfaces of the various gaseous media may further vary in size and may be adapted to the specific requirements of each such, e.g. maximum permissible pressure losses, to be adjusted.

The solution of the object according to the invention also succeeds with a radial seal according to claim 8. Advantageous further developments are specified in the subclaims dependent on claim 8.

The existing of at least two sealing arms radial seal thus has at least one sealing arm, which is formed asymmetrically. Such a design reduces the amount of pumping acting on the seals.

Furthermore, the solution of the object of the invention with a method for separating gaseous media in a regenerative heat exchanger according to claim 11 succeeds. An advantageous development is specified in the dependent claim 11 dependent claim.

The method thus consists in that in an already described heat storage body of a regenerative heat exchanger with sectors and radially arranged behind one another, throughflowable heat storage chambers, for the separation of the different gas streams, the openings the different heat storage chambers are alternately completely covered in the heat exchanger operation. That is, the heat storage chambers are permanently closed and reopened. As a result, a separation between the individual gas streams is achieved. In order to reduce the occurrence of the vibrations which are detrimental to the radial seal, which are caused by the pressure differences within the heat storage body, the heat storage chambers are covered in such a way that in the case of heat storage chambers arranged radially behind one another within a sector in each operating state of the heat exchanger at least one heat storage chamber is at most partially covered. Preferably, furthermore, the opening of at most one of these heat storage chambers is completely covered in each operating state.

Fig. 1

eine Draufsicht auf einen als Rotor ausgebildeten Wärmespeicherkörper eines Regenerativ- Wärmetauschers mit einer Radialdichtung mit zwei Dichtungsarmen, wobei ein Arm gemäß dem Stand der Technik und der andere Arm gemäß der vorliegenden Erfindung ausgebildet ist;

Fig. 2

eine perspektivische Seitenansicht des Rotors aus Fig. 1; und

Fig. 3

eine Draufsicht auf einen Ausschnitt eines als Stator ausgebildeten Wärmespeicherkörpers ei- nes Regenerativ-Wärmetauschers mit einer Radialdichtung.

The invention will be further explained with reference to embodiments shown in the drawing. They show schematically:

Fig. 1

a plan view of a formed as a rotor heat storage body of a regenerative heat exchanger with a radial seal with two sealing arms, wherein an arm according to the prior art and the other arm according to the present invention is formed;

Fig. 2

a perspective side view of the rotor Fig. 1 ; and

Fig. 3

a plan view of a section of a formed as a stator heat storage body of a regenerative heat exchanger with a radial seal.

In the various embodiments of the invention described below, the same components are provided with the same reference numerals in the figures.

Fig. 1 shows a plan view of a rotor 10 of a regenerative heat exchanger. In the center 14 of the rotor 10 is a shaft 11 around which the rotor 10 rotates. Basically, it is possible to design the rotor to rotate both clockwise and counterclockwise. The rotation of the rotor 10 by means of a motor drive (not shown here). The rotor 10 has in its interior circumferentially arranged sector walls 12, each extending radially from the shaft 11 to the outer edge 13 of the rotor 10. The sector walls 12 are rectilinear and extend from one end face of the rotor 10 to the other. All sector walls 12 have a common point of intersection in the center 14 of the rotor 10. The sector walls 12 are distributed uniformly and circumferentially in the rotor 10, so that each two adjacent sector walls 12 form equal sectors 15. Overall, the rotor 10 is divided into twenty equal sectors 15. A sector 15 is thus limited on its two sides by a respective sector wall 12, on its inner side by the shaft 11 and on its outer side by the edge 13 of the rotor 10, which is designed as a cylindrical outer jacket.

Further, a plurality of annular walls 16 are disposed within the rotor, which are each formed circumferentially and in itself closed. The annular walls 16 are arranged coaxially with each other, wherein the common axis is the axis of rotation passing through the center 14. The annular walls 16 are approximately cylindrical, wherein the portion of an annular wall 16 between two sector walls 12 is formed in each case rectilinear and is slightly angled relative to the adjacent annular wall portions. The annular walls 16 extend through the entire rotor 10 from one end face to the other. Each of the four outer subsectors 17 of each sector 15 is subdivided by a radially extending partition 18 into two heat storage chambers 19, with the four outer subsectors 17 extending through the approximately central ones Between each wall 18 each sub-sector 17 two approximately equal heat storage chambers 19 result. The use of partitions 18 is not mandatory and takes place in the present example, for design reasons. The inner two subsectors 17 are not further subdivided, so that these two subsectors 17 each form a heat storage chamber 19. In total, there are 15 heat storage chambers 19 per sector 15. In principle, the number of heat storage chambers per sector can be varied and usually results as a function of the size of the particular heat storage body present.

Due to the presence of the intermediate wall 18, the heat storage chambers 19 in the present embodiment, therefore, not only in the rotor-radial direction one behind the other, but partially also arranged side by side. The individual heat storage chambers 19 are filled with heating elements (not shown here), such as steel sheets.

Above the rotor 10, a radial seal 20 is arranged, which extends in the radial direction of the rotor from one side to the other. The radial seal 20 is enclosed in a likewise arranged on the rotor end, the course of the edge 13 of the rotor 10 following circumferential seal 21. The radial seal 20 consists of an upper seal arm 201 and a lower seal arm 202, in the horizontal, through the center 14th of the rotor 10 extending center line 23 abut. The radial seal 20, consisting of the two sealing arms 201 and 202, divides the rotor 10 into two gas areas, one to the right of the radial seal 20 and one to the left thereof. Thus, with the present rotor 10 heat from a gaseous medium to a More will be transmitted. The radial seal 20 and the circumferentially enclosing circumferential seal 21 are arranged stationary relative to the rotational movements of the rotor 10, so that the rotor 10 rotates below the radial seal 20.

The upper seal arm 201 is formed in accordance with the prior art known radial seals while the lower seal arm 202 is formed in accordance with the present invention. Sealing arm 201 is shown here in accordance with embodiments known from the prior art in order to be able to illustrate the differences between the radial seal according to the invention and the prior art more clearly. In a regenerative heat exchanger according to the invention therefore of course all sealing arms are formed according to the seal arm 202.

Both sealing arms 201, 202 each have an inner, semi-annular part 2011, 2021 which abut each other and thus form a complete ring with a circular base. In the middle of the ring, a recess for the shaft 11 is provided. The semi-ring 2011 of the sealing arm 201 is adjoined by a sealing web 2012 which extends linearly and radially outwards and which extends from the half-ring 2011 to the rotor rim 13. The sealing bar 2012 has a constant width over its entire course. The seal arm 201 is formed symmetrically, wherein the center line 14 extending vertically through the center 14 of the rotor 10 at the same time also forms its mirror axis.

In the in Fig. 1 shown rotor arm of the outer four sub-sectors 17 of a sector 15 covers each of the right one behind the other arranged heat storage chambers 19 and the two inner heat storage chambers 19. Thus, all in the rotor radial direction one behind the other heat storage chambers 19 of this sector 15 are covered by the seal arm 201. As a result, caused by the opening and closing of the individual heat storage chambers 19, due to the prevailing on the two gas sides of the rotor 10 pressure differences, vibrations are amplified.

Decisive for the present invention is that the sealing arms are designed so that they do not cover all in the rotor radial direction one behind the other heat storage chambers 19 of a sector 15 at a given time. Whether, as in the exemplary embodiment shown here, in addition to the arrangement of the heat storage chambers 19 arranged one behind the other in the rotor radial direction, some heat storage chambers 19 within a sector 15 are also partially arranged next to each other, is irrelevant in this context. One behind the other are in the example shown in each case the right heat storage chambers 19 of the outer four subsectors 17 of a sector 15 and the two inner heat storage chambers 19 and subsectors 17 of the same sector 15 and also the left heat storage chambers 19 of the four outer subsectors 17 together with the two inner heat storage chambers 19th

In contrast to the sealing arm 201, in the case of the lower sealing arm 202 according to the invention, an inner arm segment 2022 adjoins the half-ring 2021. This is cone-shaped, wherein the narrow side rests against the half-ring 2021, so that the inner segment 2022 widens in the radial direction. In the radial direction, the seal arm segment 2022 extends to the second annular wall 16, seen from the inside outwards. Thus, the inner seal arm segment 2022 is formed, the part of the first sub-sector 17 and the second sub-sector, seen from the inside out, not covered by the half-ring 2021 Cover 17 of each ring sector 15 with appropriate rotor position.

The inner seal arm segment 2022 is followed in the radial direction by a middle seal arm segment 2023. This tapers slightly in the radial direction and extends substantially in the radial direction between the second and third annular wall 16. Its two outer edges are each formed linearly. The left outer edge joins directly to the outer edge of the inner seal segment 2022 and is slightly angled relative to this. On the other hand, the right outer edge of the middle seal segment 2023 is slightly offset from the right outer edge of the inner seal arm segment 2022.

The middle seal arm segment 2023 is adjoined by an outer and last seal arm segment 2024 which extends to the edge of the rotor 13. Again, just as in the other Dichtungsarmsegmenten 2022, 2023, the outer edges are linear. They connect directly to the outer edges of the middle seal arm 2023 and are each angled towards the left. As seen in the rotor radial direction, the cross-sectional area of the outer sealing arm 2024 expands slightly, so that its greatest width is in the area of the rotor rim 13. In essence, the outer seal arm segment 2024 thus extends from the third annular wall 16 to the rotor rim 13 and thus extends approximately over three subsectors 17 in the radial direction.

Overall, the seal arm 202 is asymmetrical. The geometric design of the sealing arm 202 has the effect that, in each position of the rotor 10, at least one of the heat storage chambers 19 of a sector 15 arranged one behind the other is not or only partially covered by the sealing arm 202. In the in Fig. 1 shown position, for example, the two outer of the below the seal arm 202 located successively arranged heat storage chambers 19 are only partially covered. The other four heat storage chambers 19, which are also below the arm 202, however, are completely covered. For example, if now the rotor 10 would rotate in a clockwise direction, first the middle two of the covered heat storage chambers 19 would be opened before the two outer, partially covered heat storage chambers 19 would be completely covered. Nevertheless, each heat storage chamber 19 is once completely covered by the seal arm 202 at each rotor revolution, so that a separation of the two gas regions from each other is always ensured.

In Fig. 2 the rotor is off Fig. 1 shown in a perspective side view. All walls, that is, the sector walls 12, the annular walls 16 and the intermediate walls 18, extend through the entire rotor 10 in the axial direction from one end face to the other.

Fig. 3 shows a plan view of a section of a heat storage body 10 of a regenerative heat exchanger. The heat storage body 10 shown here is in contrast to the heat storage body of the Fig. 1 and 2 designed as a stator, ie it is stationary and thus fixed. The structure of the stator 10, that is, the division into sectors, sub-sectors and heat storage chambers, is substantially equal to the structure of the rotor of the Fig. 1 and 2 , Furthermore, two inventively designed radial sealing arms 202 are provided, which are respectively disposed above and below the stator 10 and adjacent thereto. The seal arms 202 also have as the seal arm according to the invention from the Fig. 1 and 2 an inner arm segment 2022, a middle arm segment 2023, and an outer arm segment 2024. In contrast to the sealing arm from the Fig. 1 and 2 , the outer edges of the arm segments close at the in Fig. 3 shown embodiment to the outer edges of the respective adjacent segments and are not offset relative to these. The sealing arms 202 are mounted on the underside of the outer edge of a rotary hood (not shown here) and rotate together with this around the center 14. At each end face of the stator 10, at least one rotary hood is arranged. The central axes 2025 of the two sealing arms 202 intersect at the center 14 of the stator 10 at an angle of approximately 90 °. The area enclosed by this angle is covered by the rotary hood. Since the sealing arms 202 are respectively arranged on the outer edges of the rotary hood, the regions lying outside the rotary hood are sealed off from the area enclosed by the rotary hood. The alignment of the sealing arms 202 at an angle of 90 ° to each other is preferred for the embodiments with a stator as the heat storage body 10, since this configuration corresponds to the dimensions of the rotary hoods commonly used. Frequently, two rotary hoods are arranged axially symmetrical to each other in known embodiments on each end face, so that in these embodiments a total of four sealing arms 202 according to the invention are to be arranged on each end face.

Claims (12)

A regenerative heat exchanger for heat exchange of gaseous media having a substantially cylindrical heat storage body (10) having a plurality of substantially radially extending sector walls (12), wherein each two adjacent sector walls (12) define a sector (15), and wherein each sector (15) at least two in the radial direction of the heat storage body (10) arranged one behind the other, are provided by the gaseous media through which heat storage chambers (19) are provided, which have in the region of the end faces of the heat storage body (10) openings for the inflow and outflow of the gaseous media, and at least one radial seal (20) arranged on an end face of the heat storage body (10) and designed to separate the flows of the gaseous media, which forms a covering surface for the openings of the heat storage chambers (19), the radial seal (20) and the heat storage body ( 10) relative to each other bar, and wherein the radial seal (20) is adapted to cover all heat storage chamber openings on the one end face during operation alternately completely,
characterized,
in that the radial seal (20) is designed so that it at most partially covers the opening of at least one heat storage chamber (19) from the heat storage chambers (19) of a sector (15) arranged radially one behind the other in each rotational position of heat storage body and radial seal. Regenerative heat exchanger according to claim 1,
characterized,
that the radial seal (20) is formed so that it completely covers of the successively arranged heat storage chambers (19) of a sector (15) in any rotational position at most one heat storage chamber (19). A regenerative heat exchanger according to claim 1 or 2, wherein the radial seal (20) comprises at least two seal arms (202) each extending substantially radially from the heat accumulator body longitudinal axis to the heat accumulator body edge (13),
characterized,
in that at least one sealing arm (202) is asymmetrical. Regenerative heat exchanger according to one of the preceding claims, wherein the radial seal (20) comprises at least two sealing arms (202) each extending substantially from the heat storage body longitudinal axis radially outwardly to the heat storage body edge (13),
characterized,
said seal arms (202) are radially subdivided into sealing arm segments (2022, 2023, 2024), the outer edges of one seal arm segment (2022, 2023, 2024) being respectively rectilinear and opposite the adjoining outer edges of adjacent seal arm segments (2022, 2023, 2024) , 2024) are angled and / or offset. A regenerative heat exchanger according to claim 4, wherein the heat storage body (10) comprises a plurality of coaxial annular walls (16) dividing the sectors (15) into subsectors (17),
characterized,
in that the seal arm segments (2022, 2023, 2024) each extend in the radial direction of the heat storage body via one or more subsectors (17) adjoining one another. Regenerative heat exchanger according to claim 5,
characterized,
that at least one sealing arm (202) has three sealing arm segments (2022, 2023, 2024), wherein a heat storage body longitudinal axis closest-lying inner segment (2022) is cone-shaped and widens in the radial direction, a middle segment (2023) is tapered in the radial direction and an outer segment (2024) widens in the radial direction and is angled relative to the central segment (2023). Regenerative heat exchanger according to one of the preceding claims, wherein the radial seal (20) comprises at least two sealing arms (202) each extending substantially from the heat storage body longitudinal axis radially outwardly to the heat storage body edge (13),
characterized,
that the sealing arms (202) are formed uniformly. Radial seal for use with a regenerative heat exchanger intended for heat exchange of gaseous media, the radial seal (20) comprising at least two sealing arms (202),
characterized,
in that at least one sealing arm (202) is asymmetrical. Radial seal according to claim 8,
characterized,
in that the at least one sealing arm (202) has three adjoining seal arm segments (2022, 2023, 2024) arranged one after the other in the sealing arm axial direction, wherein an outer segment (2022) is conical and widens inwardly in the axial direction, a middle segment ( 2023) tapers in the axial direction and a further outer segment (2024) widens outwardly in the axial direction and is angled relative to the central segment (2023). Radial seal according to claim 8 or 9,
characterized,
that the sealing arms (202) are formed uniformly. A method of separating gaseous media in a regenerative heat exchanger comprising a substantially cylindrical heat storage body (10) having a plurality of substantially radially extending sector walls (12), each two adjacent sector walls (12) defining a sector (15). and in each sector (15) there are provided at least two heat storage chambers (19) through which the gaseous media can flow in the radial direction and which have openings for the ingress and outflow of the gaseous media in the area of the end faces of the heat storage body (10), wherein in order to separate the streams of the gaseous media at the end faces, the openings of the heat storage chambers (19) are alternately completely covered during operation,
characterized,
that the opening of at least one heat storage chamber (19) in each operating state is at most partially covered by the heat storage chambers (19) of a sector (15) arranged one behind the other. Method according to claim 11,
characterized,
in that, in each operating state, the opening of at most one heat storage chamber (19) is completely covered by the heat storage chambers (19) of a sector (15) arranged one behind the other.

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