DE102017201808A1 - Turbine with a thermoelectric generator - Google Patents

Abstract

Turbine (7) comprising an outer skin (35), a first gas turbine section (11) with a gas turbine (19) and a second steam turbine section (13) with a steam turbine (29), wherein a thermoelectric generator (37) between the outer skin ( 35) and the second portion (13) is arranged.

Description

The invention relates to a turbine with a thermoelectric generator.

document WO 01/61768 A1 discloses a jet engine with a thermoelectric generator that utilizes temperature differences between the inside of the engine and the outside air to generate energy.

document US 2015/0047684 A1 discloses the use of a thermoelectric generator attached to a bleed air line.

document US 2016/0104831 A1 was the use of pyroelectric generators that can extract waste heat from vapor fluids.

The problem to be solved by the present invention is to provide a turbine with improved electrical power capabilities that is compact and easy to maintain.

This problem is solved by a turbine with the features of the independent claim. Preferred embodiments are defined in the dependent claims.

The turbine comprises an outer skin, a first gas turbine section with a gas turbine and a second steam turbine section with a steam turbine, wherein a thermoelectric generator is arranged between the outer skin and the second section.

In a vehicle equipped with the above-mentioned turbine, the hot exhaust gas from the gas turbine reaches 600 to 700 ° C. At the same time, the external fluid (air or water) usually has a temperature between about -85 ° C to + 40 ° C, depending on the type of vehicle, its altitude and current weather conditions. In any case, it is desirable to effectively place the thermoelectric generator between these two extremes to take advantage of a higher temperature gradient for better efficiency of the thermoelectric generator. This is the reason why a thermoelectric generator is placed between the skin and the second section with the steam turbine, where the hot exhaust of the gas turbine is used to boil liquid and drive the steam turbine.

The gas turbine can drive an electric generator and the steam turbine can drive another electric generator. As a result, electric generators can be provided which are adapted to operate effectively in the main speed and main torque range of the respective gas or steam turbine.

Alternatively, the gas turbine and the steam turbine may drive the same electric generator. As a result, a compact and more effective turbine can be provided due to the reduced space requirement for the components of the turbine. As will be apparent from the embodiment described below, electric generators may occupy valuable space within the turbine. When the number of electric generators is reduced from two to one, for example, by eliminating the need for a separate electric generator for the second section and its steam turbine, the clearance space may be used to increase the distance over which the hot exhaust gas from the first section may flow around tubes of the second section to bring the fluid therein to boil. In other words, the distance in an extending direction of the turbine is increased to transmit the thermal energy from the hot exhaust gas of the first section to the fluid of the second section. This means that not only the efficiency of the second section is increased, but also that a larger area is created for the thermoelectric generator, which can also generate more electrical energy.

A transmission may connect the gas turbine and / or the steam turbine to the electric generator. This allows the transmission, i. the speed and the torque are kept in a desired, maximum effective range for the respective generator. In the above case, where there is only one generator, the transmission may eliminate differences between the speed and torque output by the gas turbine and the steam turbine, so that the maximum efficient range for the single generator is maintained.

The second portion may include a heat recovery steam generator disposed between the first portion and the steam turbine and / or surrounding the steam turbine. When the heat recovery steam generator surrounds the steam turbine, a compact turbine may be provided. In addition, the exhaust gas of the gas turbine can be used over a longer distance, since it is not necessary to reserve space exclusively in the turbine for the steam turbine. This advantage also applies to the provision of a second steam turbine section without generator, as explained above, which can be realized either by the use of only one generator or by arranging the generator of the second steam turbine section outside the turbine.

The thermoelectric generator may be disposed between the skin and a housing of the second portion. This allows a high, uniform and constant temperature difference between the cooled by the fresh outside air outer skin of the vehicle and the heated by the exiting the gas turbine exhaust gas housing can be used.

Alternatively, a housing of the second portion and / or the outer skin may form part of thermally conductive substrates of the thermoelectric generator. Recesses or through-holes may be provided within the housing and / or the outer skin, which are configured to receive a conductive substrate of the thermoelectric generators. As a result, the heat loss can be further minimized. In addition, the turbine can be made more compact and cost-efficient, as less material is needed for the housing and / or the outer skin.

The thermoelectric generator may be disposed on a removable cover of the outer skin configured to provide temporary access to the interior of the turbine. This simplifies the maintenance of the thermoelectric generators and the sections of the turbine. In particular, since the cover can be opened not only while it remains attached to the vehicle, but also because it can be easily solved and brought to a different location for repair. This may be important because the substrates of the thermoelectric generator must be serviced or replaced due to the constant thermal and thus mechanical stress during their typical use. It is understood that multiple covers with multiple thermoelectric generators may be present.

Such cover (s) may be foldable and preferably hinged to the outer skin. This ensures quick and easy opening and closing of the turbine with direct access to the interior and the thermoelectric generator (s).

The thermoelectric generator may comprise ceramic heat conducting plates as heat conducting substrates. Ceramics are known to retain their structural shape under thermal load and are capable of withstanding very high temperatures.

In addition, a vehicle, preferably an aircraft, particularly preferably an aircraft or a drone, may comprise one of the turbines described above, preferably arranged at a rear section of the vehicle. The streamlined rear portion of a vehicle usually has a tapered shape that narrows toward the end of the rear portion. At the same time, the cross-sectional dimensions of the turbine, which has the same main direction of extension as the vehicle, may be constant or taper at an angle that is smaller compared to the rear portion of the vehicle. Thus, when the turbine is disposed in the rear portion of the vehicle, with the second portion closer to the apex of the rear portion, the distance between the outer dimensions of the turbine and the surrounding outer skin of the vehicle varies and is directed toward the second portion of the turbine where the thermoelectric generators are arranged, lower. Therefore, it is desirable to arrange the turbine, in particular the second section with the thermoelectric generators, as close to the tip of the rear section as possible. Then the distance between the second portion and the skin is minimal and the efficiency of the thermoelectric generators is maximized. If multiple thermoelectric generators are used, they may also be the same size. For this purpose, the electric generator in the second section could be dispensed with and / or the heat recovery steam generator could surround the steam turbine as explained above.

The above turbine can be used in many types of vehicles, such as watercraft, land vehicles and aircraft. Due to the very low temperatures of the outside air of a high-altitude flying aircraft, it is particularly advantageous to use the turbine in aircraft, especially aircraft, since their altitude compared to other aircraft, such as helicopters, is usually very high and constant. This also applies to drones.

• 1 eine perspektivische Ansicht eines Flugzeugs mit einer erfindungsgemäßen Turbine, die in den Heckabschnitt des Flugzeugs integriert ist,
• 2 eine Ansicht einer Anordnung der Elemente im Inneren der Turbine gemäß 1, die einen ersten Gasturbinenabschnitt auf der linken Seite und einen anschließenden zweiten Dampfturbinenabschnitt auf der rechten Seite hat,
• 3 eine Multiebenen-Ausschnittsansicht des Heckabschnitts gemäß 1 mit einer Mehrzahl von thermoelektrischen Generatoren, die zwischen einer Außenhaut der Turbine/des Flugzeugs und dem zweiten Abschnitt angeordnet sind, und
• 4 eine vergrößerte Ausschnittsansicht eines der thermoelektrischen Generatoren, die zwischen der Außenhaut und dem zweiten Abschnitt gemäß 3 angeordnet sind.

The invention will be described in more detail with reference to the accompanying drawings, in which like elements have similar reference numerals. For better readability of the drawings, only some of the similar reference numerals are given while the others are readily derivable by those skilled in the art. In these drawings is

• 1 a perspective view of an aircraft with a turbine according to the invention, which is integrated in the rear portion of the aircraft,
• 2 a view of an arrangement of the elements in the interior of the turbine according to 1 having a first gas turbine section on the left side and a subsequent second steam turbine section on the right side,
• 3 a multi-level cutaway view of the rear section according to 1 with a majority thermoelectric generators disposed between an outer skin of the turbine / aircraft and the second section, and
• 4 an enlarged sectional view of one of the thermoelectric generators, between the outer skin and the second section according to 3 are arranged.

1 shows a hybrid propulsion aircraft 1 , the three electric engines 3 on each wing. Inside the stern section 5 the plane is a turbine 7 integrated between two rear section stabilizers 9 arranged. The electric engines 3 get their energy partly from the turbine 7 and partly of electrical energy in batteries inside the aircraft 1 is stored.

2 shows the inside of the turbine 7 according to 1 , This type of turbine 7 is known as a "combination cycle combustion turbine" for generating electrical energy. In this type of turbine 7 are a first gas turbine section 11 and a second steam turbine section 13 intended. Fresh air through two arrows on the left in 2 is displayed, enters a compressor 15 fuel, then fuel through a fuel inlet 17 added. The compressed air / fuel mixture is burned and then drives a gas turbine 19 , A first output shaft 21 transmits that through the gas turbine 19 generated torque to a first electric generator 23 , From the turbine 19 Exiting hot exhaust gas then enters a heat recovery steam generator 25 the second steam turbine section 13 one where inside of pipes 27 flowing liquid is heated and evaporated to a subsequent steam turbine 29 drive. A second output shaft 31 transfers that from the steam turbine 29 generated torque to a second electric generator 33 , The of these electric generators 23 . 33 generated electrical energy is the batteries of the aircraft 1 or directly to the electric engines 3 fed. The batteries may be structural batteries that have weight advantages over removable batteries, or supercapacitors

3 shows the combination cycle combustion turbine 7 inside the stern section 5 of in 1 shown aircraft 1 is arranged. It can be seen that an outer skin 5 of the plane 1 the turbine 7 surrounds and an installation space for the turbine 7 encloses. In addition, thermoelectric generators 37 between the outer skin 35 and the second section 13 arranged. 3 further shows that some of the thermoelectric generators 37 on a removable cover 39 the outer skin 35 are arranged so that the detachable cover 39 foldable on the outer skin 35 is hinged and thus a temporary access to the interior of the turbine 7 granted to a maintenance of the thermoelectric generators 37 and the second steam turbine section 13 to enable.

4 shows a possible arrangement of a thermoelectric generator 37 the in 3 shown thermoelectric generators 37 , The upper wavy arrow shows the exhaust gas flow direction around the fluid pipes 27 and along an inner heat-conducting wall of a housing 41 the second steam turbine section 13 , On the other side of the heat-conducting wall of the housing 41 is one of two thermally conductive substrates 43 , which serves as a ceramic heat-conducting plate 43 which is in direct contact with the n-type and p-type semiconductors 45 . 47 that is, to the other of the thermally conductive substrates 49 lead, which also as a thermally conductive plate 49 is trained. The straight arrows down in 4 indicate the direction of flow of the external fluid, in which case the external fluid is outside air. Consequently, the thermoelectric generator 37 in direct heat-conducting contact with the hot housing 41 the second steam turbine section 13 and in heat-conducting contact with the cold skin 35 of the plane 1 , which is cooled by the outside air. For a high altitude, ie over 10,000 m flying aircraft, the outside air temperature falls below -50 ° C, while the hot exhaust gas from the gas turbine 19 600 reached up to 700 ° C. Consequently, the resulting temperature gradient across the semiconductors 45 . 57 of the thermoelectric generator 37 well above 200 ° C if losses due to intermediate materials are taken into account.

• • Die thermoelektrischen Generatoren 37 können zwischen der Außenhaut 35 des Flugzeugs angeordnet sein und ebenso Teile des ersten Gasturbinenabschnitts 11 einschließlich der Gasturbine 19 des ersten Gasturbinenabschnitts 11.
• • Der thermoelektrische Generator 37 oder Generatoren 37 kann/können nur an der lösbaren Abdeckung 39 angeordnet sein. Es kann auch eine Mehrzahl von lösbaren Abdeckungen 39 vorgesehen sein.
• • Obwohl die Gasturbine 19 und die Dampfturbine 29 zwei separate elektrische Generatoren 23, 33 antreiben, können Sie auch den gleichen elektrischen Generator antreiben. Zu diesem Zweck kann eine der Abtriebswellen 21, 31 hohl sein, um die Hindurchführung der anderen der Abtriebswellen 21, 31 zu ermöglichen, sodass beide Abtriebswellen 21, 31 zu dem gleichen Generator der zwei Generatoren 23, 33 führen können. Eine weitere Möglichkeit ist, dass der einzige Generator zwischen dem ersten und dem zweiten Abschnitt 11, 13 angeordnet ist, sodass Abtriebswellen der Gasturbine 19 und der Dampfturbine 27 jeweils von zwei verschiedenen Seiten zu dem Generator führen können.
• • Alternativ oder zusätzlich dazu kann ein Getriebe die Gasturbine 19 und/oder die Dampfturbine 29 mit dem jeweiligen der zwei elektrischen Generatoren 23, 33 oder dem einzigen elektrischen Generator verbinden, um die Transmission, d. h. die Drehzahl und das Drehmoment der jeweiligen Abtriebswellen 21, 31 für den/die elektrischen Generator(en) anzupassen.
• • Alternativ oder zusätzlich dazu kann die Dampfturbine 29 im Inneren des Wärmerückgewinnungsdampfgenerators 25 angeordnet sein, sodass der Wärmerückgewinnungsdampfgenerator 25 die Dampfturbine 29 umgibt. Zu diesem Zweck wären die Fluidrohre 27 in Umfangsrichtung um die Dampfturbine 29 angeordnet.
• • Um die Effizienz des thermoelektrischen Generators 37 zu erhöhen, können wärmeleitenden Substrate 43, 49 an der Außenhaut 35 und/oder dem Gehäuse 41 vorgesehen sein.
• • Das Gehäuse 41 des zweiten Dampfturbinenabschnitts 13 kann sich weiter erstrecken, um auch das Gehäuse 41 des ersten Gasturbinenabschnitts 11 zu sein.
• • Obwohl die obige Ausführungsform ein Flugzeug 1 mit der hier offenbarten Turbine 7 zeigt, können viele Fahrzeugarten, beispielsweise Luftfahrzeuge, insbesondere Flugzeuge oder Drohnen mit einer derartigen Turbine 7 ausgestattet sein.

The following modifications of the above embodiment are provided:

• • The thermoelectric generators 37 can between the outer skin 35 be disposed of the aircraft and also parts of the first gas turbine section 11 including the gas turbine 19 of the first gas turbine section 11.
• • The thermoelectric generator 37 or generators 37 Can / can only on the removable cover 39 be arranged. It can also have a plurality of removable covers 39 be provided.
• • Although the gas turbine 19 and the steam turbine 29 two separate electric generators 23 . 33 You can also power the same electric generator. For this purpose, one of the output shafts 21 . 31 be hollow to the passage of the other of the output shafts 21 . 31 to allow both output shafts 21 . 31 to the same generator of the two generators 23 . 33 being able to lead. Another possibility is that the only generator between the first and the second section 11 . 13 is arranged so that output shafts of the gas turbine 19 and the steam turbine 27 can each lead from two different sides to the generator.
• Alternatively or additionally, a transmission may be the gas turbine 19 and / or the steam turbine 29 with the respective one of the two electric generators 23 . 33 or the single electric generator to adjust the transmission, ie the speed and the torque of the respective output shafts 21, 31 for the / the electric generator (s).
• • Alternatively or additionally, the steam turbine can 29 inside the heat recovery steam generator 25 be arranged so that the heat recovery steam generator 25 the steam turbine 29 surrounds. For this purpose, the fluid pipes would be 27 in the circumferential direction around the steam turbine 29 arranged.
• • To the efficiency of the thermoelectric generator 37 can increase, heat-conductive substrates 43 . 49 on the outer skin 35 and / or the housing 41 be provided.
• • The housing 41 the second steam turbine section 13 can continue to extend to the housing 41 of the first gas turbine section 11 to be.
• Although the above embodiment is an airplane 1 with the turbine disclosed here 7 can show many types of vehicles, such as aircraft, especially aircraft or drones with such a turbine 7 be equipped.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 0161768 A1 [0002]
• US 2015/0047684 A1 [0003]
• US 2016/0104831 A1 [0004]

Claims (11)

Turbine (7), comprising: an outer skin (35), a first gas turbine section (11) with a gas turbine (19) and a second steam turbine section (13) having a steam turbine (29), wherein a thermoelectric generator (37) is disposed between the outer skin (35) and the second portion (13). Turbine (7) after Claim 1 in that the gas turbine (19) drives an electric generator (23) and the steam turbine (29) drives another electric generator (33). Turbine (7) after Claim 1 wherein the gas turbine (19) and the steam turbine (29) drive the same electric generator. Turbine (7) according to one of the preceding claims, wherein a transmission, the gas turbine (19) and / or the steam turbine (29) to the electric generator (23, 33) connects. A turbine (7) according to any one of the preceding claims, wherein the second section (13) comprises a heat recovery steam generator (25) disposed between the first section (11) and the steam turbine (29) and / or surrounding the steam turbine (29). Turbine (7) according to one of the preceding claims, wherein the thermoelectric generator (37) between the outer skin (35) and a housing (41) of the second portion (13) is arranged. Turbine (7) after one of Claims 1 to 5 in which a housing (41) of the second section (13) and / or the outer skin (35) forms part of heat-conducting substrates (43, 49) of the thermoelectric generator (37). A turbine (7) according to any one of the preceding claims, wherein the thermoelectric generator (37) is disposed on a detachable cover (37) of the outer skin (35) configured to provide temporary access to the interior of the turbine (7). Turbine (7) after Claim 8 wherein the cover (39) is foldable and is preferably hinged to the outer skin (35). Turbine (7) according to one of the preceding claims, wherein the thermoelectric generator (37) comprises ceramic heat-conducting plates (43, 49) as heat-conducting substrates (43, 49). Vehicle, preferably aircraft, particularly preferably aircraft (1) or drone with a turbine (7) according to one of the preceding claims, which is preferably arranged on a rear section (5) of the vehicle.

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