EP2258999A1 - Method for temperature-dependant adjustment of a seal gap on a regenerative heat exchanger and related adjustment device - Google Patents

Abstract

The method involves causing control movement for rotor seals by rod bodies (13, 14), that is provided in a control device (10), where the control movement for the seal is caused depending on a temperature change of a gas flow. The rod bodies are section-wise arranged in chambers. The rod bodies are separately and heat-exhangeably controlled by the respective chambers by a control medium such that different temperature loadings are provided for the rod bodies. An independent claim is also included for a thermally controlled control device for a regenerative heat exchanger for adjusting a sealing gap between an adjustable seal and a circulating rotor.

Description

The invention relates to a method for temperature-dependent setting of a sealing gap between an adjustable seal and a rotating rotor of a regenerative heat exchanger, according to the preamble of claim 1. The invention further relates to a relevant adjusting device according to the preamble of the independent claim. The invention further relates to a regenerative heat exchanger.

Regenerative heat exchangers of the type in question are used for air preheating (Luvo) and / or for gas preheating (Gavo). For this purpose, a heat-emitting and a heat-absorbing gaseous medium are passed in countercurrent along heat storage bodies. The heat storage body, such as Heizblechpakete are arranged in a stator or rotor.

If the heat storage bodies are arranged in a rotor (Ljungström principle), they are rotated through the cold and warm gas streams, so that a continuous exchange of heat between the gas streams is made possible. In the arrangement in a stator (Rothemühle principle), the heat exchange is made possible by the fact that on both Statorstirnseiten rotating gas duct connections, so-called rotary hoods are arranged so that the gas streams rotate through the stator. In both variants, therefore, the heat storage body alternately flows through all the existing gas flows.

• Verstellung per Hand (manuelles Nachstellen),
• Mehrpunktverstellung über Stellsystem mit Stellzylindern, und
• elektrische Stellantriebe, die automatisch gesteuert werden.

To prevent leaks, various rotor seals are required both on a stator and in particular on a rotor. On a rotor, these are radial seals, circumferential seals and axial or jacket seals. Due to changing thermal conditions, a constant readjustment of these seals is required during operation in order to obtain defined sealing gaps. For adjusting or adjusting the sealing gaps, the following possibilities are known:

• Adjustment by hand (manual readjustment),
• Multipoint adjustment via positioning system with adjusting cylinders, and
• electric actuators that are automatically controlled.

From the DE 2 162 248 A is a thermally controlled adjusting device for temperature-dependent setting of a sealing gap known. The seals are hereafter connected via spring bolts with alternating thermally influenced folding bellows. In the closed bellows there is an enclosed volume of gas which is heated or cooled by ambient operating gases, thereby changing the gas pressure, which is utilized as a force for a seal. Furthermore, thermostatically influenced rod bodies are known from the prior art, the temperature-dependent, axial length change is converted into an actuating movement for the seal. These concepts are disadvantageous in many ways.

Proceeding from this, the present invention seeks to provide a simple, automatic and cost-effective way to adjust seals on a regenerative heat exchanger.

This object is achieved by a method having the features of claim 1. The object is further achieved by an adjusting device and by a regenerative heat exchanger with the features of the independent claims. Preferred and advantageous developments are the subject of the respective dependent claims.

The invention is procedurally achieved by a method for temperature-dependent setting of the sealing gap between an adjustable seal and a rotating rotor of a regenerative heat exchanger by means of at least one adjusting device comprising at least one alternating thermally influenced rod body whose temperature-dependent, axial length change converted into an actuating movement for the seal becomes. It is provided that this rod body is at least partially disposed in at least one chamber and this chamber at least partially or partially flows through a control medium and / or flows around which acts directly or indirectly Wechselheizhermisch on this rod body, the temperature level of the control medium to a Temperature level corresponds to a flowing through the rotor gas flow, so that in response to a change in temperature of this gas flow an axial change in length of this rod body and a corresponding adjusting movement for the seal is brought about.

A rod body is a solid which is characterized by an axial longitudinal extent which is a multiple of its cross-sectional dimensions. An alternately influenced rod body is formed of a material or material which undergoes a volume change determined by the thermal expansion coefficient in the event of a temperature change, which may inter alia. leads to an axial change in length.

An alternating thermally influenced rod body is arranged at least in sections in a chamber. The rod body concerned is thus at least partially surrounded by at least one chamber or penetrates at least one such chamber. The wall of such a chamber is preferably formed fluid-tight. For direct alternating thermal influencing of the rod body, a control medium can be introduced into such a chamber, which according to the invention represents a thermal level of the gas volume flow passing through the rotor. For a better heat exchange, the surface of the rod body can be designed accordingly. It is also possible to cover the surface of the rod body by a coating in front of e.g. protect aggressive acting control medium. For an indirect alternating thermal influence of the rod body, this chamber can be flowed around by the control medium, as explained in more detail below. Both possibilities can be combined with each other.

The rotating rotor preferably serves to transfer heat from a first volume of gas flow, e.g. a flue gas volumetric flow, to a second gas volumetric flow, e.g. to a fresh air or air volume flow. Such technology is used in particular in power plants.

A control medium may be a gaseous or a liquid medium, but must be such that it can flow through a conduit system or the like. According to the invention, it is provided that the temperature level of this control medium corresponds to a temperature level of a gas volume flow flowing through the rotor, that is to say that a mutual correspondence exists. This may be the first or the second gas volume flow. It is preferably provided that it is the second gas volume flow, i. the air volume flow is, and its temperature level after flow through the rotor or at the rotor outlet (on the hot rotor side) is relevant for the adjustment of the sealing gap.

A basic principle of the invention resides in the recognized correlation between the temperature level of a gas volume flow flowing through the rotor and at a time determined temperature forming rotor deformation. Such a rotor deformation is for example a crowning of the rotor, as this example in the DE 2 162 248 A descriptive is described. This requires adjusting the sealing gap by tracking the seals. This affects the radial seals and the circumferential seals on both sides of the rotor, as well as the axial or jacket seals. The invention enables a simple but extremely effective tracking of rotor seals, which at any time quasi automatically the sealing gaps are optimally adjusted under different operating conditions.

According to the invention, it is provided that a temperature level of the control medium corresponds to a temperature level of a gas volume flow flowing through the rotor. This can be technically realized in different ways. For example, e.g. conceivable that the control medium via a heat exchanger with the gas flow in thermal communication. Furthermore, it is conceivable that a partial volume flow is branched off from the gas volume flow, which serves as a control medium. Furthermore, it is conceivable to detect a temperature of the gas volume flow by measurement and to set the properties of the control medium in a targeted manner thereafter. These possibilities can also be combined with each other. Below some of the possibilities as preferred developments are explained in detail.

• der/die wechselthermisch beeinflussten Stabkörper und die diese umgebende Kammer bzw. Kammern ist/sind weitgehend ortsunabhängig anordenbar,
• der/die wechselthermisch beeinflussten Stabkörper sind im Wesentlichen nur einem bestimmten Steuermedium ausgesetzt,
• die Erfindung ist umsetzbar für Radial-, Umfangs- und Axialdichtungen,
• die betreffenden Dichtungen folgen bei allen Laständerungen automatisch der Rotorverformung,
• es sind keine elektrischen, pneumatischen, hydraulischen und/oder vergleichbare Stellantriebe erforderlich,
• es ist keine elektrische Verkabelung erforderlich,
• die Dichtspalte sind individuell ortsabhängig auch während des Betriebes einstellbar,
• die Dichtspalte sind während des Betriebs gleichbleibend, d.h. geringe Leckagen,
• hohe Lebensdauer, und
• geringe Instandhaltungskosten.

The invention has many advantages, such as:

• the alternating thermally influenced rod body and the chamber or chambers surrounding it are / can be arranged largely independently of location,
• the rod body (s) thermally affected are essentially exposed to only one particular control medium,
• the invention can be implemented for radial, circumferential and axial seals,
• the respective seals automatically follow the rotor deformation at all load changes,
• no electric, pneumatic, hydraulic and / or comparable actuators are required
• no electrical wiring is required
• the sealing gaps are individually adjustable depending on the location, even during operation,
• the sealing gaps are consistent during operation, ie small leaks,
• long life, and
• low maintenance costs.

According to a preferred embodiment, it is provided that as a control medium, a partial volume flow diverted from a flowing through the rotor gas flow and at least Such a rod body is supplied, for which this rod body is at least partially disposed in at least one chamber which flows through the diverted partial volume flow at least partially and / or flows around, so that in response to a change in temperature of this gas flow an axial change in length of this rod body and a corresponding adjusting movement for the seal is brought about. The partial volume flow is preferably branched off on the hot rotor side from the second gas volume flow, ie the air volume flow. After branching, the partial volume flow can continue to be subdivided into a plurality of partial volume flows.

According to a preferred embodiment, it is provided that the diverted partial volume flow is returned after flowing through and / or recirculation of the chamber in the same gas volume flow or introduced into another flowing through the rotor gas flow. For example, a partial volume flow diverted from the air volume flow is returned to the air volume flow or introduced into the flue gas volume flow. The return or introduction can take place before the entry of the respective gas volume flow into the rotor or afterwards. By skillful return or initiate a pressure difference opposite the branch can be used, which drives the partial volume flow. Furthermore, such a measure proves to be energetically advantageous.

According to a preferred embodiment it is provided that additionally a sealing gap measurement is carried out by means of at least one sensor, on the basis of which, determined or regulated by a control unit, at least one essential property of the control medium or the partial volume flow is changed by a required axial change in length of this rod body and to bring about a corresponding adjusting movement for the seal. Essential properties of the control medium or partial volume flow are in particular its pressure, temperature and flow volume. These properties can be e.g. be influenced by heating and / or cooling, as well as by a blower. The idea is to induce or control a defined change in length of a rod body and thus a defined actuating movement for the seal by influencing the control medium or the partial volume flow.

According to a preferred embodiment, it is provided that an adjusting device comprises a plurality of such bar bodies, which cooperatively bring about an adjusting movement for the seal, wherein at least two of these bar bodies can be thermally controlled separately via respective chambers by means of the control medium or partial volume flow. This will be explained in more detail below in connection with the figures.

According to a particularly preferred embodiment, it is provided that an initially cool control medium is supplied to at least one rod body and then heated to be supplied to further rod bodies. As a result, good control accuracy can be achieved with regard to the sealing gap. This will be explained in more detail below in connection with the figures.

The object is achieved by means of a device thermally controlled adjusting device for a regenerative heat exchanger for adjusting a sealing gap between an adjustable seal and a rotating rotor, wherein the adjusting device comprises at least one alternating thermally influenced rod body whose temperature-dependent, axial length change converted into an actuating movement for the seal becomes. Here, it is provided that at least one alternating thermally influenced rod body is at least partially disposed in at least one chamber and this chamber directly (ie directly) or indirectly (ie indirectly) can be acted upon with a control medium, which (directly or indirectly) causes the alternating thermal influence of this rod body ,

For this adjusting device apply mutatis mutandis, the above statements on the method according to the invention and vice versa. As a control medium, a branched partial flow of a heated by the rotor gas flow is preferably provided. The adjusting device according to the invention is particularly suitable for carrying out the method according to the invention and provided for this purpose.

According to a preferred embodiment, it is provided that the chamber can be flowed through by the control medium at least partially or in sections, for which purpose it has at least one inlet and at least one outlet. This leads to a direct or immediate Wechselheizmische influencing the rod body. Such a chamber may be formed as a flow chamber. This will be explained in more detail below in connection with the figures.

According to a preferred embodiment, it is provided that the chamber is at least partially or partially flowed around by the control medium, for which purpose the wall is double-walled (ie with an enclosed cavity) and / or formed with a cable jacket. This leads to an indirect or indirect Wechselheizmische influencing the rod body.

According to a preferred embodiment, it is provided that a relative movement between this rod body and the chamber is made possible. Alternatively, no relative movement between this rod body and the chamber is possible.

According to a preferred embodiment, it is provided that this rod body is designed as a tube. Preferably, the tube has an annular cross-section, whereby other cross-sectional shapes are possible. Likewise, massive versions are possible.

According to a preferred embodiment, it is provided that the chamber is placed on the rod body. Preferably, the chamber is attached to this rod body and surrounds it completely in the radial direction. The length of the chamber corresponds in the axial direction in about 60 to 80% of the axial length of the rod body, so that this preferably projects beyond the chamber at both axial ends or projects. In the axial direction of the rod body can also be provided a plurality of chambers, e.g. can be acted upon differently with control media.

According to a preferred embodiment, it is provided that the wall of the chamber is provided with at least one bellows-like section, which enables a temperature-dependent volume compensation. This will be explained in more detail below in connection with the figures.

According to a preferred development it is provided that a plurality of these rod bodies are included, which are arranged at least in sections parallel and / or serially in a chamber. Also, a plurality of such chambers may be provided, in each of which a group of rod bodies are arranged. The number of rod bodies arranged together in a chamber may vary. Alternatively and / or additionally, it is provided that a plurality of these rod bodies are included, which are arranged at least in sections in separate chambers. As a result, this includes all technically possible arrangement combinations.

If a plurality of rod bodies is included, it is provided according to a preferred development that at least two rod bodies are formed from the same material. In particular, all rod bodies are made of the same material. Even with a same choice of material, the rod body can expand or contract differently due to different axial lengths and / or different temperature stresses. alternative and / or additionally it is provided that at least two rod bodies are formed from different materials.

According to a preferred embodiment it is provided that at least a first chamber with an inlet for a non-heated or cool control medium, e.g. Air, and at least one second chamber is provided with an inlet for a heated control medium, so that in each of these chambers arranged therein rod body by appropriate supply of a control medium (air) can be exposed to a defined temperature difference. The idea is to provide an independent system with an adjustable temperature for the control medium or an adjustable flow volume with which the axial length change can be specifically influenced. This will be explained in more detail below in connection with the figures.

According to a preferred embodiment, it is provided that the first chamber and the second chamber are in fluid communication and that the first chamber of the second chamber is connected upstream of a preferred flow direction of the control medium. The flow connection is realized by means of a piping system. A preferred pipe diameter of this piping system is approximately 20 mm. Further details will be explained below in connection with the figures.

According to a preferred development, at least one heating and / or cooling device is included. In particular, it is provided that a heating device for the auxiliary heating of the control medium is arranged between an outlet of the first chamber and the inlet of the downstream second chamber. Such a heating device is preferably integrated in a possible pipeline system. Preferably, this heating means is e.g. bridged by means of a bypass. This is especially the case when the control medium is at least partially a warm or hot partial volume flow, which is branched off or derived from one of the gas volume flows passing through the rotor. Additional heating might not be required in this case. Possibly. however, cooling might be required. This will be explained in more detail below in connection with the figures.

According to a preferred development, at least one fan device is included. In particular, it is provided that between the outlet of the first chamber and the inlet of the downstream second chamber, a blower device for the auxiliary promotion of the control medium is arranged. Such a blower device is preferably in a possible pipeline system involved. By means of the blower device may also be the pressure in the control medium can be increased. Further details will be explained below in connection with the figures.

According to a preferred development, at least one valve device is included. In particular, it is provided that at least one valve device is included for controlling the volume flow of the control medium. Such a valve device is preferably integrated in a possible pipeline system. Further details will be explained below in connection with the figures.

According to a preferred development, at least one filter device is included. In particular, it is provided that this filter device is arranged in the flow direction in front of the rod bodies and should prevent any dirt deposit on the rod body. Such a filter device is preferably integrated into a possible pipeline system.

According to a preferred development, at least one sensor for measuring the sealing gap is included.

According to a preferred development, a control unit is included. In particular, it is provided that this control unit or control device controls a heating device and / or cooling device, a fan device and / or a valve device on the basis of the sensor measurement signal. The control unit is preferably an electronic control unit, which in particular comprises a software-based control algorithm.

The object is also solved by a device according to the invention by a regenerative heat exchanger comprising at least one thermally controlled adjusting device according to the invention. In particular, it is provided that this regenerative heat exchanger can be operated or operated by the method according to the invention. For this regenerative heat exchanger, the preceding statements apply mutatis mutandis.

According to a preferred development of this regenerative heat exchanger, it is provided that the seal which can be adjusted by means of the adjusting device is a radial seal, a circumferential seal and / or a jacket seal. In particular, it is provided that the adjustable by means of the adjusting device according to the invention seal is a radial seal and / or a peripheral seal on the cold rotor side and / or on the hot rotor side.

Fig. 1:

den Rotor eines Regenerativ-Wärmetauschers in einer Seitenansicht;

Fig. 2:

ein Ausführungsbeispiel einer erfindungsgemäßen Stellvorrichtung in einer Schnitt- ansicht;

Fig. 3:

ein alternatives Ausführungsbeispiel einer erfindungsgemäßen Stellvorrichtung in ei- ner Schnittansicht;

Fig. 4:

eine weiteres Ausführungsbeispiel einer erfindungsgemäßen Stellvorrichtung mit ei- ner beispielhaften Beschaltung; und

Fig. 5:

den zeitlichen Verlauf der Stabkörpertemperatur bei einem Sprung der Temperatur des Steuermediums in einem Diagramm.

The invention will be explained in more detail with reference to FIGS. They show schematically:

Fig. 1:

the rotor of a regenerative heat exchanger in a side view;

Fig. 2:

an embodiment of an adjusting device according to the invention in a sectional view;

3:

an alternative embodiment of an adjusting device according to the invention in a sectional view;

4:

a further embodiment of an adjusting device according to the invention with an exemplary wiring; and

Fig. 5:

the time course of the rod body temperature at a jump in the temperature of the control medium in a diagram.

Fig. 1 shows a generally designated 1 rotor of a regenerative heat exchanger according to the invention. The rotor 1 has a vertical axis of rotation 2, the direction of rotation is indicated by the arrow R by way of example. A first gas volume flow 3, which is, for example, a hot flue gas volume flow, flows through the rotor 1, and a second gas volume flow 4, which is, for example, a cool air volume flow. By means of the rotor 1, heat is transferred from the first gas volume flow 3 to the second gas volume flow 4, whereby the first gas volume flow 3 is cooled when passing through the rotor 1 and the second gas volume flow is warmed up when passing through the rotor 1. Due to the existing temperature conditions, the upper rotor end side can be referred to as hot end side (or rotor side) A and the lower rotor end side as cold end side (or rotor side) B. With U is exemplified a sealing gap.

To prevent leaks on the rotor 1, circumferential seals 7a and 7b, radial seals 8a and 8b, as well as axial seals or jacket seals 9a and 9b are provided. These seals 7a, 7b, 8a, 8b, 9a and 9b may be formed segmented. Due to changing thermal conditions, a constant readjustment of these seals is required during operation in order to maintain defined sealing gaps. This adjustment of the seals 7a, 7b, 8a, 8b, 9a and 9b by means of at least one adjusting device 10 according to the invention, as will be explained in more detail below. For a seal 7a, 7b, 8a, 8b, 9a and 9b a plurality of such adjusting devices 10 may be provided, which are operated independently or in coordination with each other.

Fig. 2 shows a simple embodiment of an adjusting device 10 according to the invention in a schematic sectional view. The adjusting device 10 is fixedly attached to a housing section or frame 5 of the regenerative heat exchanger. The actuating device 10 comprises an actuating section 11 and a control section or adjusting drive 12. In the actuating section a plurality of rod bodies 13 and 14 are arranged, the axial lengths of which vary as a function of a current temperature. The rod bodies 13 are formed with equal axial lengths and shorter than the rod body 14.

The outer rod body 13, wherein the outer arrangement is merely exemplary, are attached to a fixed bearing 15 with their left-side axial ends. At a temperature-induced axial change in length of the rod body 13, these changes in length are transferred to the right-side floating bearing 16. The translatory motion V on the floating bearing 16 is transmitted via the rod body 14 to a rocker arm 20, which moves the relevant seal via an adjusting bolt 21, which is indicated by a double arrow X. The nuts 22 are used for manual adjustment of the seal. The illustrated lever mechanism is merely exemplary. Thus, other mechanical actuators are readily feasible. Also, the shown diagonal arrangement of the rod bodies 13 and 14 is merely exemplary.

The rod body 13 are made of a material that has a high degree of volume change with temperature changes. The rod body 14 is formed from a material which has a significantly lower volume change with the same degree of temperature change, so that the changes in length of the rod body 13 are not compensated by a change in length of this rod body 14. The actuating mechanism can also be described as follows: the rod bodies 13 with a high thermal expansion initiate an adjusting movement, which is transmitted to the adjusting drive 12 via at least one rod body 14 with a low thermal expansion. The number of individual rod body types is merely exemplary, with it being preferred that a plurality of rod bodies 13 are provided in order to be able to generate high actuating forces. The rod body 13 are subjected to pressure and can therefore be referred to as pressure rods. The or the rod body 14 are claimed to train and can therefore be referred to as tension rods.

The rod bodies 13 and 14 are arranged in a chamber 17 which is formed by a fluid-tight wall 17a. In the embodiment shown, the rod bodies 13 and 14 completely surrounded by the chamber 17. The chamber 17 has, for example, an inlet 18 and an outlet 19. Via the inlet 18 and the outlet 18, the chamber 17 can be flowed through by a control medium, which is indicated by flow arrows. The control medium flows directly around the rod body 13 and 14, which occupy the current temperature of the control medium in the sequence. A temperature change in the control medium causes an axial change in length of the rod body 13, whereby an adjustment movement X is initiated for the seal, as explained above.

As the control medium, a gaseous medium is preferable. In particular, it is provided that a partial volume flow serves as the control medium, which of the second, to be reheated gas volume flow or the air stream 4 after its passage through the rotor 1, i. on the hot front side A of the rotor 1, is branched off. Due to a correlation between the temperature of this gas flow 4 at the hot end A of the rotor 1 and a self-adjusting rotor deformation, the actuator 10 can be mechanically adjusted so that the seal in question is readjusted at a certain temperature change with a defined distance, which then almost automatically he follows. A certain travel length X can be e.g. be determined by the gear ratio in the mechanical actuator 12 or by selecting the material of the rod body 13 and 14 or their geometric dimensions.

By way of the flow volume and / or the flow pressure of the control medium in the chamber 17, the reaction time required by the rod bodies 13 and 14 to adapt to a current temperature of the control medium can, if necessary, be varied. In order to be able to change the flow volume and / or the flow pressure, a heating and / or cooling device as well as a blower device can be included. Furthermore, under certain circumstances, it may be necessary to change the properties of the control medium in a targeted manner, in order thereby to bring about a desired positioning movement X for the seal. This will be described below in connection with a further embodiment with reference to FIG Fig. 3 explained in more detail.

Fig. 3 shows an alternative embodiment of an actuator 10. The structure is substantially identical to that in Fig. 3 shown construction. Deviating here, however, provided that the control medium, the rod body 13 and 14 does not flow around directly and thus no direct alternating thermal influence takes place, but that the control medium is passed through a hollow chamber 1 7b in the wall 1 7a and thus not in direct contact with the rod bodies 13 and 14 passes, for which the wall 17a is double-walled. The rod bodies In this case, 13 and 14 are only indirectly changed thermally by the control medium transferring its temperature level to the air enclosed in the chamber 17 (possibly also a gas or a liquid). Such a design offers advantages, for example with regard to the seal. Furthermore, more aggressive control media may be used without adversely affecting the seals and / or the rod bodies 13 and 14. Instead of a hollow chamber 17b or in addition, the wall 17a of the chamber 17 may be at least partially surrounded by a line casing such as a spiral flow line, through which flows the control medium.

According to Fig. 4 An alternative positioning device 10 comprises a rod body 14 designed as a tension rod and a plurality of rod bodies 13 designed as pressure rods. These are each enclosed in a fluid-tight chamber 171 and 172, which are here designed as hollow-cylindrical casings with circular end faces. The chambers 171 and 172 are formed as flow chambers and are flowed through directly. The chambers 171 and 172 are quasi put on the rod body 13 and 14 from the outside. The chambers 171 and 172 are part of a piping system which includes an inlet 181, a plurality of connecting conduits 40, an outlet 192, a plurality of valves 51 to 54, a filter 60, a controllable fan 60, and a controllable electric heater 70 includes. The two flow chambers 171 and 172 are connected in series. The connecting lines 40 of the piping system have, for example, an inner diameter of about 20 mm.

The pressure rods 13 and the tension rod 14 are arranged parallel to each other and allow in the manner described above, a temperature-dependent adjustment of a seal, which is an example of a peripheral seal 7 here. The sealing gap to the rotor 1 is designated by U. While the pressure rods 13 are held at their upper axial ends fixed to a fixed bearing 15, the lower axial ends can move in a movable bearing 16. This movement in the floating bearing 16 is transmitted via the tie rod 14 and an unspecified lever linkage as an adjusting movement on the seal 7, which is representative designated by U. The compression bars 13 and the tension rod 14 have different thermal expansion coefficients for this purpose. Alternatively and / or additionally, these could be formed, for example, with different cross sections. In the example shown, the rod body 13 and 14 are further formed with different axial lengths.

In a preferred structural embodiment, the rod body 13 and / or 14 are formed as round rods with a rod diameter of about 10 to 20 mm. Its axial length is e.g. about 2 m. The chambers 171 and 172 are preferably circular-cylindrical and have e.g. an inner diameter of about 100 mm.

The chambers 171 and 172 have a substantially invariable volume. Through these chambers 171 and 172, a control medium can be conducted (flow chambers), which directly exerts thermal influence on the pressure rods 13 and the tension rod 14. The chambers 171 and 172 are fixedly connected at their end faces with the associated pull and push rods 13 and 14, respectively. To compensate for the temperature-related changes in length, the walls of the chambers 171 and 172 folding bellows 173 and 174 on.

In the illustrated embodiment, unheated ambient air having a temperature of, for example, 20 ° C is sucked in via the inlet 181 at one end into the chambers 171 surrounding the pressure rods 13. This "air" is used in the following as a control medium. It flows around the pressure rods 13 almost over their full length and is then discharged via the outlet 191 at the other end. From there it passes via a connecting line 40 to the electric heater 70 where it is heated before being fed to the inlet 182 of the chamber 172 surrounding the pull rod 14. If necessary, the heating device 70 can also be a cooling device or a combined heating / cooling device. The power of the heater 70 is controlled by a control unit 80, e.g. with a sensor 90 for measuring the sealing gap U communicates. In the connecting line 40, a blower device 60 is further arranged, by means of which the flow in the piping system can be generated or at least supported. The blower device 60 can also be controlled by the control unit 80. In addition, a filter unit 50 is arranged upstream of the heating device 70, which in particular cleans the control medium or the air of solids.

The air heated by means of the heating device 70 and / or the fan device 60, after it has flowed along the tension rod 14 over almost its full length, finally discharged via the outlet 192 and preferably the supplied gas volume flow 4 (not shown).

With the explained arrangement, a different temperature application of the rod body 13 and 14 is possible. This results in a good controllability. Furthermore, an indirect regulation of a sealing gap as a function of the temperature of the gas volume flows and a possibly diverted from this partial volume flow possible. There is thus the advantage that a flow which is uniquely predetermined by the chambers 171 and 172 can be generated along the rod bodies 13 and 14, so that a defined heat transfer to the rod bodies 13 and 14 is ensured. Thus, it is also possible to determine the dependence of the axial length changes of the temperature or the flow volume of the air (or the control medium) in a simple manner and adjust the sealing gap U on the seal 7. Since the invention can be embodied as an independent system, it can be used in a variety of ways. Because of the relatively simple components, the system works reliably and can be built at low cost.

As an alternative or supportive to the heating device 70 and / or the blower device 60, heated air can also be branched off from the hot end side of the rotor 1 and fed via a further inlet 41 at a node 42 into the connecting line 40. The feed is controlled by the valves 51 and 52, which are also controlled by the control unit 80. By closing the valve 51, i.A. prevents undesired return of the heated air to the pressure rods 13.

A bypass 44 leads to the heating device 70 with a valve 53 arranged therein, with which the air can optionally be led past the heating device 70. The flow volume of the air through the heater 70 may be partially or completely shut off via the downstream valve 54. The valves 53 and 54 also serve to determine the flow volume and, if necessary, by a mixing ratio, the temperature of the air at the inlet 182. The valves 53 and 54 are also controlled by the controller 80. By the way, a bypass is also possible on the blower device 60 and / or the filter device 50.

Fig. 5 shows the time course of the rod body temperature S at a jump of the temperature L of the control medium in a diagram. It can be seen that the rod body temperature S approaches the temperature L of the control medium, which flows through the chamber 17 (or 171 and / or 172), in a time-sluggish manner, wherein the axial length change adjusts synchronously to this course S. This temporal behavior must ideally be taken into account in the design of the adjusting device 10. The temporal behavior can be influenced, for example, via the blower device 60 or the heating / cooling device 70, which is then possibly initiated by the control device 80.

Claims (28)

Method for temperature-dependent setting of a sealing gap (U) between an adjustable seal (7, 7a, 7b, 8a, 8b, 9a, 9b) and a rotating rotor (1) of a regenerative heat exchanger by means of at least one adjusting device (10), the at least one alternating thermally influenced rod body (13, 14) whose temperature-dependent, axial length change in an adjusting movement (X) for the seal (7, 7a, 7b, 8a, 8b, 9a, 9b) is implemented,
characterized,
this rod body (13, 14) at least in sections in at least one chamber (17, 171, 172) is arranged and this chamber (17, 171, 172) at least partially flows through or flowed around by a control medium, which directly or indirectly alternately thermally changes to this rod body (13, 14), wherein the temperature level of the control medium corresponds to a temperature level of a gas volume flow (3, 4) flowing through the rotor, such that an axial change in length of this rod body (13, 14) is dependent on a temperature change of this gas volume flow (3, 4) ) and a corresponding adjusting movement (X) for the seal (7, 7a, 7b, 8a, 8b, 9a, 9b) is brought about. Method according to claim 1,
characterized,
that as a control medium a partial flow flowing from a through the rotor (1) Gas flow rate (3, 4) branched off and at least one such rod body (13, 14) is supplied, to which this rod body (13, 14) at least in sections (at least in one chamber 17 , 171, 172) is arranged, which is flowed through or flows around the diverted partial volume flow, so that in dependence of a change in temperature of this gas volume flow (3, 4) an axial change in length of this rod body (13, 14) and a corresponding adjusting movement (X) for the Seal (7, 7a, 7b, 8a, 8b, 9a, 9b) is brought about. Method according to claim 2,
characterized,
that the partial volume flow, after flowing through or flowing around the chamber (17, 17a, 17b), is led back into the same gas volume flow (3, 4) or the flow of the control medium or into another gas volume flow (4, 3) flowing through the rotor or a liquid flow becomes. Method according to one of the preceding claims,
characterized,
in that a sealing gap measurement is additionally carried out by means of at least one sensor (90) on the basis of which, determined by a control unit (80), at least one essential characteristic of the control medium or partial volume flow is changed in order to achieve a required axial change in length of this rod body (13, 14). and a corresponding adjusting movement (X) for the seal (7, 7a, 7b, 8a, 8b, 9a, 9b) to bring about. Method according to claim 4,
characterized,
in that an adjusting device (10) comprises a plurality of such rod bodies (13, 14) which cooperatively effect an adjusting movement (X) for the seal (7, 7a, 7b, 8a, 8b, 9a, 9b), at least two of these rod bodies (13 , 14) can be thermally controlled separately via respective chambers (171, 172) by means of the control medium or partial volume flow. Thermally controlled adjusting device (10) for a regenerative heat exchanger for setting a sealing gap (U) between an adjustable seal (7, 7a, 7b, 8a, 8b, 9a, 9b) and a rotating rotor (1), wherein the adjusting device (10 ) comprises at least one alternating thermally influenced rod body (13, 14) whose temperature-dependent, axial length change is converted into an adjusting movement (X) for the seal (7, 7a, 7b, 8a, 8b, 9a, 9b),
characterized,
in that at least one rod body (13, 14) that is thermally changed is arranged at least in sections in at least one chamber (17, 171, 172) and this chamber (17, 171, 172) can be acted upon directly or indirectly by a control medium which controls the thermal interaction of the same Rod body (17, 171, 172) brought about. Adjusting device (10) according to claim 6,
characterized,
in that the chamber (17, 171, 172) can be flowed through or at least partially by the control medium, for which purpose it has at least one inlet (18, 181, 182) and at least one outlet (19, 191, 192). Adjusting device (10) according to claim 6,
characterized,
in that the chamber (17, 171, 172) can be flowed around at least partially by the control medium, for which purpose its wall (17a) has a double wall and / or is formed with a line jacket. Adjusting device (10) according to claim 6, 7 or 8,
characterized,
that a relative movement between this rod body (13, 14) and the chamber (17, 171, 172) is made possible. Adjusting device (10) according to one of claims 6 to 9,
characterized,
that this rod body (13, 14) is rod-shaped or tubular. Adjusting device (10) according to one of claims 6 to 10,
characterized,
in that the chamber (17, 171, 172) is placed on the rod body (13, 14). Adjusting device (10) according to one of claims 6 to 11,
characterized,
in that the wall of the chamber (17, 171, 172) is provided with at least one bellows-type section (173, 174), which makes possible a temperature-compensated volume compensation. Adjusting device (10) according to one of claims 6 to 12,
characterized,
a plurality of said rod bodies (13, 14) are included, which are arranged at least in sections parallel and / or serially in a chamber (17, 171, 172). Actuating device (10) according to claim 6 to 13,
characterized,
that a plurality of said rod bodies (13, 14) are included, which are arranged at least in sections in separate chambers (171, 172). Actuator (10) according to claim 14,
characterized,
in that at least one first chamber (171) is provided with an unheated control medium inlet (181) and at least one second chamber (172) with a heated control medium inlet (182) so that the chambers (171, 172 ) each arranged rod body (13, 14) can be exposed by appropriate supply of a control medium a defined temperature difference. Adjusting device (10) according to claim 15,
characterized,
in that the first chamber (171) and the second chamber (172) are in fluid communication and in that the first chamber (171) is connected upstream of the second chamber (172) with respect to a preferred flow direction of the control medium. Actuating device (10) according to claim 16,
characterized,
in that a heating device (70) or a cooling device for the auxiliary heating or cooling of the control medium is arranged between an outlet (191) of the first chamber (171) and the inlet (182) of the downstream second chamber (172). Actuating device (10) according to claim 16 or 17, characterized
characterized,
in that between the outlet (191) of the first chamber (171) and the inlet (182) of the downstream second chamber (172) there is arranged a blower device (60) for the auxiliary conveying of the control medium. Actuating device (10) according to one of claims 16 to 18,
characterized,
in that at least one valve device (51, 52, 53, 54) is included for controlling the volume flow of the control medium. Adjusting device (10) according to one of claims 6 to 19,
characterized,
in that at least one sensor (90) for measuring the sealing gap (U) is included. Actuator (10) according to claim 20,
characterized,
in that a control unit (80) is included which actuates a heating device (70), a blower device (60) and / or a valve device (51, 52, 53, 54) on the basis of the sensor measurement signal of the sensor (90). Adjustment device (10) according to one of claims 13 to 21,
characterized,
in that at least two rod bodies (13, 14) are formed from the same material. Adjustment device (10) according to one of claims 13 to 22,
characterized,
in that at least two rod bodies (13, 14) are formed from different materials. Adjusting device (10) according to one of claims 6 to 23,
characterized,
in that at least one filter device (50) is included. A regenerative heat exchanger comprising at least one thermally controlled adjusting device (10) according to one of claims 6 to 24. Regenerative heat exchanger according to claim 25,
characterized,
in that the seal which can be adjusted by means of the adjusting device (10) is a radial seal (8a, 8b), a peripheral seal (7a, 7b) and / or an axial or jacket seal (9a, 9b). Regenerative heat exchanger according to claim 25,
characterized,
in that the seal which can be adjusted by means of the adjusting device (10) is a radial seal (8a, 8b) and / or a circumferential seal (7a, 7b) on the cold rotor side (B) and / or on the hot rotor side (A). Regenerative heat exchanger according to one of claims 25 to 27,
characterized,
that it is operated by a method according to one of claims 1 to 5.

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