EP3074181A1

EP3074181A1 - Method and device for cleaning a jet engine

Info

Publication number: EP3074181A1
Application number: EP14806234.2A
Authority: EP
Inventors: Holger Appel; Klaus Bräutigam
Original assignee: Lufthansa Technik AG
Current assignee: Lufthansa Technik AG
Priority date: 2013-11-29
Filing date: 2014-11-28
Publication date: 2016-10-05
Anticipated expiration: 2034-11-28
Also published as: US20160298488A1; EP3074181B1; EP3189934A1; CA2931952A1; US10247033B2; EP3189934B1; US20170114663A1; CN106102997B; CN106102997A; CA2931952C; WO2015079032A1; US9903223B2; DE102013224639A1

Abstract

The invention relates to a method for cleaning a jet engine by means of a cleaning medium that contains solids, which are introduced into the engine by means of a carrier gas using at least one nozzle. The pressure of the carrier gas is 1 to 5 bar, preferably 2 to 4 bar. The outlet of the at least one nozzle is arranged at a radial distance from the rotational axis of the engine corresponding to 0.5 to 1.2 times the radius of the upstream-oriented inlet opening of the first compressor stage, and the main outlet direction of the nozzle includes, with the axis of rotation of the engine, an angle of 10 to 30°, preferably 12 to 25°, more preferably 16 to 19°. The invention further relates to a correspondingly configured nozzle unit and to an arrangement consisting of such a nozzle unit, and to an engine.

Description

Method and device for cleaning a jet engine plant

The invention relates to a method, a device, such as an arrangement for cleaning an aircraft jet propulsion ^¬ plant.

Aircraft jet engines have one or more Com ^¬ pressorstufen, a combustion chamber, and one or more turbine stages. In the turbine stages, the hot combustion gases from the combustion chamber release some of their thermal and mechanical energy, which is used to drive the compressor stages. Jet engines of commercial airliners today mainly have a so-called turbofan, which is arranged upstream of the compressor stages and usually has a considerably larger diameter than the compressor stages. The turbofan is also driven by the turbine ^¬ step and leaves a significant portion of the total as engine air flowing through the so-called secondary air stream to the compressor stages, the combustion chamber un flow past the turbine stages. By such a side stream, the efficiency of an engine can be significantly increased and also provided for improved noise insulation of the engine. Contamination of an aircraft jet engine can lead to a reduction in efficiency, resulting in increased fuel consumption and thus increased Umweltbelas ^¬ tion result. The pollution can be caused for example by insects, dust, salt spray or other environmental pollution. Parts of the engine can be miniert by combustion residues of the combustion chamber konta ^¬. These impurities form a deposit on the air-flowed parts of an aircraft engine and affect the surface quality. Thus the thermodynamic efficiency of the engine is adversely impressive ^¬. In this case, in particular, the blades in the compressor stages are mentioned whose contamination has a considerable influence on the efficiency of the entire engine.

It is known to remove contaminants

Engine with a cleaning fluid, usually hot water, to clean. From WO 2005/120953 an arrangement is known in which a plurality of Reinigungsdü ^¬ sen upstream of the turbofan or the compressor stages are arranged. The cleaning fluid is then sprayed into the engine. The engine can thereby rotate in the so-called dry-cranking, ie the blades of the engine rotate without burning kerosene in the combustion chamber. By the introduced into the engine Rei ^¬ nigungsflüssigkeit contaminants to be washed away from the surfaces of the engine components. Alternatively to the use of water as a cleaning medium, the use of coal dust is known. The pulverized coal, like the water, is injected into the engine through nozzles. and removes impurities from surfaces due to abrasive effects. However, the surface of the engine parts is ^¬ attacked by the coal dust, which is why a cleaning medium such as coal dust is not suitable for regular cleaning of aircraft engines. In addition, when cleaning with coal dust remain unwanted remains of the cleaning material in the engine back ^¬ . WO 2009/132847 A1 discloses an apparatus and a method for cleaning jet engines using solid carbon dioxide as the cleaning medium.

The invention has for its object to provide a method, an apparatus and an arrangement that allow improved cleaning of aircraft engines.

This object is achieved by a method according to the An ^¬ claim 1, a nozzle device according to claim 13 or 14 and an arrangement according to claim 24. Advantageous developments emerge from the dependent claims.

The invention thus relates to a method for cleaning a jet engine with a cleaning medium containing solids. The solids are introduced ^¬ through at least one nozzle into the engine by means of a carrier gas ^¬. The cleaning medium thus comprises according to the invention at least a carrier gas and solids, preferably from ^¬ finally carrier gas and solids. A carrier gas is a gaseous at the application temperature medium, preferably compressed air can be used. The solids may be stable solids at the application temperature such as plastic beads, glass beads or coal dust act. However, preferably thermolabile solids such as solid carbon dioxide and / or ice (water ice) are used.

The invention has recognized that effective cleaning of, in particular, the compressor or compressor of an engine is possible by the claimed process parameters. According to the invention, the cleaning medium follows the flow in the compressor and achieves a cleaning effect in all stages of the compressor, in particular also in the rearmost stages. According to the invention, in particular he ^¬ enough that thermolabile solids in particular Koh ^¬ dioxide or ice not give back in the front stages of the compressor, all kinetic energy and / or sublimate or melt. Instead, the solids according to the invention only give a basic impulse, which promotes them into the engine. Subsequently, the solid is taken from the gas stream in the engine and thus promoted in the rearmost compressor stages. The pressure of the carrier gas is therefore erfin ^¬ tion according to 1 to 5 bar, preferably 2 to 4 bar. A ^¬ be Sonder preferred pressure is 3 bar. In order to allow the desired entrainment of the solids by the air ^¬ stream in the compressor without the solids abut prematurely against the inner or outer compressor ^¬ wall, the exit direction of the nozzle (in the context of the invention, this term denotes the Hauptaus- direction) as possible extend far into the compressor, without this exit direction or their imaginary axis touches the walls of the compressor. To this end the invention provides that the exit of the we ^¬ is nigstens arranged a nozzle in a radial distance from the Rotati ^¬ onsachse of the engine, of the 0.5 to l, 2-fold, preferably from 0.5 to lfachen the radius of the upstream facing inlet opening of the first compressor stage corresponds. The outlet is therefore in radial direction ^¬ closer to the outer wall of the compressor than at the axis of rotation of the engine or compressor. The Hauptaus ^¬ passage direction of the nozzle is according to the invention obliquely domestic nen to the rotational axis of the engine directed towards and closes with this axis an angle of 10 ° to 30 °, before ^¬ preferably 12 to 25 °, more preferably 16 to 19 °.

The combination of these process parameters according to the invention allows efficient cleaning of the compressor (core engine) of jet engines over their entire length, in particular also in the rear stages in the direction of flow. A particularly preferred in the invention Kompres ^¬ sorgeometrie has a curved flow channel, the front having a in flow direction, radially inner convex curvature of the flow channel and arranged one in the flow direction behind, radially outer convex curvature of the flow channel. In the context of the invention, the term of the front, radially inwardly disposed convex curvature denotes an inward curvature of the flow channel in the direction of the axis of rotation of the jet engine and the notion of downstream arranged radially outwardly disposed convex curvature an outward curvature of the flow channel. In a particularly preferred grain pressorgeometrie advantageous variant of the invention ^shown SEN process may preferably include the at least one nozzle with the axis of rotation of the engine before ^¬ an angle the main exit direction, which lies between the SS and α; where β is the angle between the rotational axis of the engine and a first straight line, which is arranged as a tangent to the upstream, radially inwardly disposed convex curvature of the flow channel of the compressor and at the downstream arranged radially outwardly disposed convex curvature of the flow channel runs; and α is the angle between the Ro ^¬ tion axis of the engine and a second straight line, which is arranged as a tangent to the radially outer edge of the inlet of the compressor (compressor) and at the downstream in the flow direction, radially inwardly arranged convex Curvature of the flow channel runs. Fer ^¬ ner of the outlet of the at least one nozzle preference ^¬ example in a radial distance from the axis of rotation of the engine can be arranged, which stands between the Radialab- the intersections of the first and second lines to that radial plane in which the outlet of the at least one nozzle is arranged. In the context of the term dung OF INVENTION ^¬ radial plane denotes a rotation axis arranged perpendicular to the plane.

The solids are inventively preferably selected from the group consisting of solid carbon dioxide and What ^¬ sereis. Particularly preferred is solid carbon dioxide. Koh ^¬ dioxide and / or water can be particularly preferably used in the form of pellets. Also possible is the use of water ice as crushed ice (so-called crushed ice). Pellets can be produced in a so-called pelletizer from liquid CO ₂ and are well storable. It can be provided that a supply device already conveys prefabricated pellets with the aid of the carrier gas to the nozzle device. But it is also possible that the supply device has a device to produce liquid carbon dioxide from solid carbon dioxide pellets or fes ^¬ th carbon dioxide snow, and this transported with the Trä ^¬ gergas to the nozzle device. In both cases, the solid carbon dioxide from the nozzles of Düsenein ^¬ direction exits and enters the to-clean engine. In the document "Carbon Dioxide Blasting Operations" of the US armed forces, the technique for the production of CO ₂ is -. Pel lets ^¬ pellets are described, for example, by a compaction of solid CO ₂ (for example, flakes.) In a pelletizer o-. . the like obtained the production of ice pellets (water ice) the skilled artisan and need here kei ^¬ ner clarifying in one variant of the inventive method, the cleaning medium may be solid carbon dioxide and water ice in Mas ^¬ senverhältnis. 5: 1 to 1: 5, preferably 1: 2 to 2:. 1 aufwei ^¬ sen principle, it is already known (WO

2012/123098 AI) to provide a mixture of pellets of carbon dioxide and ice as a solid abrasive for cleaning Oberflä ^¬ chen. However, it has been shown that this mixture can be used in a particularly advantageous manner for cleaning jet engines, since the greater part of the solid carbon dioxide already sublimated in the front region of the compressor and this on the one hand by the kinetic energy of the collision and by thermal Ef ^¬ cleans. Due to the induced by the carbon dioxide ^¬ heat-cooling-voltage impurities detached from the surfaces of the engine parts. The dung OF INVENTION ^¬ according added in the mixture of ice has a higher hardness and durability as a solid carbon dioxide. On the one hand, this improves the mechanical cleaning effect due to the kinetic energy of the impact and is better able to penetrate the compressor as a whole up to the rear stages and also to develop a cleaning effect there as well. The mixture used in the invention causes the one hand a largely complete details of the uniform cleaning of all steps of the Kompres ^¬ sors, and contributes to other only comparatively small Men ^¬ gen water into the engine. According to the invention, this introduced water is for the most part removed from the engine by the carrier gas used (preferably air) or by the air stream flowing through the engine during dry-cranking.

The average size of the pellets used is preferably in the range from 1 to 10 mm, preferably about 3 mm. If elongated pellets are used, their length can be, for example, 3 to 6 mm, the dimension transverse to the longitudinal extension, for example, about 3 mm ,

The solids are preferably used at a mass flow of 100 to 2000 kg / h, more preferably 200 to 1500 kg / h, more preferably 350 to 2000 kg / h, more preferably 400 to 2000 kg / h, further preferably 350 to 1200 kg / h , more preferably 400 to 1200 kg / h, more preferably 100 to 600 kg / h, more preferably 200 to 500 kg / h, further preferably 350 to 450 kg / h introduced. Be ^¬ carries the duration of the cleaning operation (pure beam time without breaks) preferably 1 to 15 min, more preferably 2 to 10 min, more preferably 4 to 8 min. Thus ^¬ example, during a cleaning operation, from 1.5 to 200 kg before ^¬ preferably 35 to 200 kg, more preferably 40 to 200 kg, more preferably 40 to 120 kg, more preferably 1.5 to 50 kg, more preferably from 3 to 35 kg, further preference ^{¬ as} 7 to 25 kg of solids are introduced into the engine.

Preferably, the nozzle or the nozzles are flat jet nozzles, for example flat fan nozzles with an opening angle of 1 °.

The dry-cranking or rotation of the jet engine during the cleaning process is preferably carried out with a fan speed of 50 to 500 min ^-1 , preferably 100 to 300 min ^-1 , more preferably 120 to 250 min ^-1 . Especially be ^¬ vorzugt is a fan speed between 150 and 250 min ^-1. Cleaning may also take place while the engine is idling. The speed is then preferably 500 to 1500 min ^"1 .

The invention further provides a nozzle device with at least one nozzle, which is designed to introduce cleaning medium containing solids into a jet engine, which has means for non-rotatable connection with the shaft of the turbofan of a jet engine, and which has a rotary coupling to which a line ^¬ connection is connectable. In a first variant of the invention it is provided that the lines for guiding the cleaning medium from the rotary coupling to the nozzles are formed such that the curvatures present in the lines are formed in such a way that that solid carbon dioxide can follow the flow unhindered and does not sublime at the pipe walls due to too narrow radii of curvature. In a second, either independent or preferably to be combined with the first variant of the invention embodiment of the invention, it is provided that the connection of the nozzle-side outlet of the rotary coupling takes place with the inlet of the at least one nozzle by means of a flexible hose.

A both variants of the invention connecting basic idea is that the lines for the cleaning medium from the rotary coupling to the outlet of the nozzle gentle as possible and not too large transition angle or angle of curvature aufwei ^¬ sen to the so a low friction as possible promotion of hard ^¬ materials by To allow carrier gas. In the second variant of the invention, the use of preferably removable hoses by their flexibility allows a sufficiently gently curved guidance of Fest ^¬ materials. On the other hand, the hoses ensure that the nozzle device for storage and transportation is sufficiently small and not spreading, in particular ^¬ sondere can be loaded vorzugt disassembled for transport and storage hoses and transported separately or sto ^¬ preserves.

A line connection connecting the nozzle means to a supply device, this supply means provides the cleaning medium available (for example, in the tank) and may be provided with operating and Antriebseinrichtun ^¬ gen, pumps, energy storage or the like be. It is preferably designed as a mobile, in particular mobile ^¬ bare unit.

The nozzle device has one or more nozzles. Sonders loading it when the nozzle device comprises two nozzle least Wenig ^¬ is preferred.

Due to the non-rotatable connection with the shaft Dü ^¬ seneinrichtung during dry-cranking, ie the slow

Spin the engine without injecting kerosene, co-rotate.

The term rotary coupling between the nozzle device and the line connection is to be understood functionally and refers to any device which is suitable for producing a sufficiently stable, preferably pressure-resistant and tight connection between the stationary part of the line connection and the nozzle device co-rotating with the fan. The purpose of the rotary joint is to direct the cleaning medium from the stationary supply device into the co-rotating nozzle device and then to let it out of the nozzles.

The rotary coupling is preferably located in the front region of the nozzle device, ie in that region which, in the mounted state, points upstream, ie away from the inlet of the jet engine. The outlet opening of the nozzles is accordingly provided in the axial end region of the nozzle device facing away from it, that is to say in the assembled state in the downstream end region. This arrangement makes it possible to fit the nozzles either through the interspaces of the blades during assembly on the shaft of the fan of a turbofan engine, so that they are arranged directly in front of the first compressor stage, or at least selectively aligned so that they spray through the spaces between the blades of the turbofan di ^¬ rectly to the first compressor stage.

Preferably, the nozzle-side outlet of the rotary coupling is located diametrically opposite the inlet. The inlet has before ^¬ Trains t in the axial direction and upstream, so that in Rich ^¬ tung, is carried out in the assembled state of the nozzle device of an engine of the Anstrom of the engine. The diametrically opposite outlet is then also downstream in the axial direction. In this way, the cleaning medium within the rotary coupling undergoes no or at most a slight change in the flow direction, so that there is no undesirable friction of the solids by curvatures or too narrow curvatures of the lines.

In the inventive nozzle means the nozzle are arranged o- of the nozzle generally in the radially outer region, while the rotary coupling is usually arranged in the rotational ^¬ axis or axis of rotation. In order to enable a guide of the cleaning medium through lines or flexible Schläu ^¬ che with small curvatures, it is advantageous if the rotary coupling, which usually represents the upstream axial end of the nozzle device, from the means for non-rotatable connection with the shaft of the Turbofans, which usually represent the downstream end of the nozzle device according to the invention, has a sufficiently large axial distance, which allows or facilitates a Füh ^¬ tion of the lines from the rotary joint to the nozzle with sufficiently large radii of curvature. For example, the axial distance of the Rotary coupling of said means for rotationally fixed connection with the shaft of the turbofan 0.2 to 2 m, more preferably 0.5 to 2 m, more preferably 0.75 to 1.25 m amount. Furthermore, the guidance of the cleaning medium from the inlet of the at least one nozzle to the nozzle outlet may be substantially rectilinear. Within the actual nozzle, there is thus no deflection of the cleaning medium between inlet and outlet. It can be provided that the nozzle device so on

Turbofan is attached, that their nozzles point between the show ^¬ blades of the turbo fan. As a result, a targeted cleaning of the compressor stages and subsequently the combustion chamber or turbine stages is achieved. The nozzles, which rotate during dry-cranking, coat the first compressor stage evenly over the entire circumference. The cleaning medium is not affected by the turbofan arranged in front of it in the flow direction, and the spraying direction of the cleaning medium can thus be adapted to the angle of attack of the blades of the first compressor stage.

The mass distribution of the nozzle device is preferably rotationally symmetrical about its axis of rotation. In this way, no significant additional imbalance is introduced during co-rotation of the nozzle device. For this purpose, the rotary coupling preferably sits essentially centrally on the axis of rotation of the device according to the invention in the mounted state. Preferably, the nozzle means on at least two or more nozzles, which are preferably driven rotationssymmet ^¬ distributed around the axis of rotation. The nozzles are before Trains t ^¬ designed as flat-jet nozzles which may have an opening angle of 1 °, preferably at ^¬ play. The radial distance of the nozzle outlet from the rotation ^¬ axis of the engine and thus the nozzle device according to the invention, for example, 200 to 800 mm, more preferably 400 to 750 mm, more preferably 600 to

700 mm, more preferably 200 to 400 mm, more preferably ^¬ 230 to 300 mm, more preferably 260 to 280 mm. These values depend on the drive to be cleaned and can vary accordingly. The preferred distance of 260 to 280 mm is suitable, for example, the

Clean the core engine of a CF6-50 engine. The before ^¬ ferred distance of 600 to 700 mm, for example geeig ^¬ net to clean the core engine of a CF6-80 engine. At mounted nozzle device is the Düsenaus- then occurs in the area of the radially outer edge of the A ^¬ passage of the compressor.

The jet plane or main exit direction of the nozzle (s) is preferably directed obliquely inwards towards the rotational axis of the engine and closes with this axis

Angle of 10 to 30 °, preferably 12 to 25 °, further preferably ^¬ 16 to 19 °. The mentioned values may vary depen ^¬ gig from the driving gear to be cleaned and should be chosen so that the main discharge direction of the nozzle (or its imaginary extension) as far as possible in the

Compressor protrudes, without touching inner or outer walls of the Ver ^¬ poet.

In a preferred embodiment, the beam plane or main outlet direction of the nozzle (s) with the axis of rotation of the engine may preferably be located at an angle including ^¬ SEN, between the SS and α; where β is the angle between the rotational axis of the engine and a first Straight lines, which run as a tangent to the front, in the flow direction, radially inwardly disposed convex curvature of the flow channel of the compressor and at the flow ^¬ direction behind it, arranged radially outwardly convex curvature of the flow channel; and α is the angle between the axis of rotation of the drive ^¬ plant and a second straight line, which is arranged as a tangent to the radially outer edge of the inlet of the compressor (compressor) and at the downstream in the flow direction, arranged radially inwardly convex curvature Flow channel runs.

The means for non-rotatable connection with the shaft of the turbofan turbofan preferably includes attachment means for attachment to the turbofan blades, such as suitably formed hooks for hooking the nozzle means to the trailing edges (the downstream edges) of the blades of the turbofan.

The nozzle means may comprise for non-rotatable fixing to the shaft of the turbofan means for substantially form-fitting mounting on the shaft hub of the fan on ^¬. Turbofan engines usually have on the upstream end of the shaft of the turbofan on a conically curved hub, which should improve the flow behavior of the air. On this hub, the ent ^¬ speaking means for rotationally fixed connection can be placed. "Substantially positive" in this context means that the shape of the shaft hub is used for the intended positioning of the nozzle device and for fixing in the desired position. that the entire surface of the shaft ^hub must be positively closed ^¬ closed.

For example, the means may comprise one or more ring parts with which they can be ^¬ relies on the shaft hub. At a plurality of ring parts, these have a different diameter, which is reasonable fit to the diameter of the shaft hub in the entspre ^¬ sponding areas. For example, two axially spaced rings of different diameters can be provided, with which the nozzle device is positioned and centered on the shaft hub.

Tensioning cables can preferably be provided for further fixing. For example, the nozzle device can be centered by means of the ring parts on the shaft hub of the fan and then clamped with tension cables which are fixed to the trailing edge of the turbofan blades. According to the invention spring means for biasing the tension cables may be provided so that the nozzle device is pressed with a defined force to the shaft hub. The tensioning cables are preferably attached (for example by means of ^hooks ) to the turbofan blades, preferably at the rear edge thereof.

A supply device for the cleaning medium preferably has storage tanks for the components of the cleaning ^¬ medium and at least one pump for pressurizing the nozzle device with the cleaning medium. A carrier gas, preferably air, is used. The carrier gas may be pretreated, for example it may be dried so as to take up and remove the largest possible amount of water introduced into the engine can. It may be provided that to cool the carrier gas, so that ice pellets and / or carbon dioxide pellets in the carrier gas stream ^¬ are resistant as possible. Alternatively, however, it is also possible to heat the carrier gas stream, for example to about 80.degree. This appears eg. For Kohlendi ^¬ oxide pellets initially absurd, since it reduces the resistance of the pellets. However, the invention has recognized that the warm carrier gas stream supplies thermal energy to the engine interior, which compensates for the cooling by the cleaning medium. This prevents from excessive cooling ^¬ From the solid carbon dioxide only can develop an insufficient cleaning effect (due to low temperature difference). Also, it can be prevented from freezing in the engine interior remaining water in the case of the use of water ice as a cleaning medium. As the carrier gas acts over a very short period of time to the cold pellets before they can develop their cleaning ^¬ effectively, the influence of the heated carrier gas is not or hardly significant falls on the pellets.

The invention further relates to an arrangement of a jet engine and a nozzle device according to the invention. The arrangement is characterized in that the nozzle means is arranged so that its nozzle (s) is / are directed towards the inlet of the jet engine.

The jet plane or main exit direction of the nozzle (s) is preferably directed obliquely inwards towards the axis of rotation of the drive ^¬ plant and closes with this axis an angle of 10 to 30 °, preferably 12 to 25 °, further preferably ^¬ 16 to 19 ° one. Preferably, the outlet of the at least one nozzle in egg ^¬ nem radial distance from the rotational axis of the engine at ^¬ arranged corresponding to the 0.5 to l, 2-fold, preferably from 0.5 to Hachen the radius of the upstream directed Eintrit- töffnung the first compressor stage equivalent. The exit ^¬ is thus in the radial direction closer to the outer compressor wall than at the axis of rotation of the engine or compressor. In a preferred embodiment, the main exit direction of the nozzle (s) with the axis of rotation of the

Engine include an angle which is between ß and α; where β is the angle between the rotational axis of the engine and a first straight line, which runs as a tangent to the upstream, radially inwardly disposed convex curvature of the flow channel of the compressor and at the downstream arranged radially outwardly disposed convex curvature of the flow channel; and wherein α is the angle between the ro tationsachse of the engine and a second straight line that is arranged as a tangent to the radially outer edge of the inlet run of the compressor (compressor) and the in Strö ^¬ flow direction behind, radially inner convex Curvature of the flow channel runs. FER ner of the outlet of the at least one nozzle preference ^¬ example in a radial distance from the axis of rotation of the engine can be arranged, which ^¬ stands between the Radialab the intersections of the first and second lines to that radial plane in which the outlet of the at least one nozzle is arranged.

It can preferably be provided that the nozzle device rotationally fixed to the shaft of the fan of the jet engine the rotary axes of the fan of the jet engine and the nozzle device are arranged substantially concentrically, the nozzles of the nozzle device have a radial distance from the common axis of rotation of the jet engine and the device, the 0.5 to l, 2 times, preferably the 0, 5 to 10 times the radius of the first com ^¬ pressorstufe corresponds, and arranged the outlet openings of Dü ^¬ sen in the axial direction behind the plane of the turbofan and / or arranged the nozzles in the interstices of the turbofanaufaufein and / or aligned with the interspaces of the turbo ^¬ vanes are so that the jets can pass through the plane of the turbofan substantially unhindered. An embodiment of the invention will be explained below with reference to the drawings. Show:

Fig. 1 is a first view of a nozzle device according to the invention;

FIG. 2 shows a second view of a nozzle device according to the invention; FIG.

Fig. 3 is a view of a particularly preferred compres- sorgeometrie.

The nozzle device has two ring elements 101, 102, with the aid of which the nozzle device is placed on a shaft hub of the turbofan of a jet engine. In the mounted state, the ring elements 101, 102 enclose the shaft hub substantially in a form-fitting manner. Among the De ^¬ tails of the compound of the nozzle means having a shaft hub is made to WO 2009/132847 Al, the disclosure of which is also made the subject of the application ahead ^¬ by reference. The two ring elements 101, 102 are connected to one another by radial struts 104. At the upstream tip of the nozzle device (with respect to the flow direction of the engine), a generally designated 105 rotary coupling is arranged, which has an inlet 110. The rotational coupling 105 may be formed ^¬ al ternatively separated from the junction with the pressure ports 106 and, for example, by a short

Hose piece to be connected, whose flexibility helps compensate for possible axle deviations during assembly. Two pressure hoses 108 can be connected to the pressure connections 106 (only one pressure hose 108 is shown in FIG. 1 for the sake of clarity), whose respective other end communicates with the inlet of the flat jet nozzles 107 is connected. The length and flexibility of these pressure hoses 108 is dimensioned so that they are formed in the mounted state in the bends so that they allow a trouble-free För ^¬ tion of the jet medium. Due to the large radii of curvature, solids and in particular pellets can be transported in a low-friction manner from the input of the rotary coupling 105 to the nozzle outlet 109 of the flat-jet nozzles 107. The two flat jet nozzles 107 are thus fed with cleaning medium.

The axial distance of the rotary coupling 105 from the outlet openings 109 of the nozzles 107 in the exemplary embodiment is about 1.2 m. This distance is sufficient that the pressure hoses ^¬ 108, the inlets of the nozzles 107 without excessive curvatures of these pressure hoses 108 with the outlets 106 the rotary coupling 105 can connect. The radial distance of the nozzle outlet 109 from the axis of rotation is about 270 mm in the exemplary embodiment. It is designed to clean a CF6-50 engine. The Hauptaustrittsrich- processing of the nozzles 107 (which corresponds substantially to its longitudinal axis) closes with the axis of rotation of Düsenein ^¬ direction an angle of 18 °.

The attachment of the nozzle device to the shaft hub of a turbofan is effected by means of tensioning cables, as described in detail in WO 2009/132847 A1.

To clean a jet engine the Düseneinrich ^¬ tion is placed on the shaft hub of the turbo fan and fixed to the blades of the turbo fan. The engine is put in Dre ^¬ hung (dry-cranking). About the rotary joint 105 and the pressure hoses 108, the flat jet nozzles 107 are fed with cleaning medium from a supply device, not shown. This cleaning medium covers the inlet of the first compressor stage over its entire circumference and thus performs the cleaning.

FIG. 3 shows the schematic section of an engine with a particularly preferred compressor geometry. Forms are off a Turbofanschaufel 301 and the downstream inlet 303 of the compressor 304 relative to Ro ^¬ tationsachse 308 of the engine. The inlet 303 has ei ^¬ NEN radially outer edge 305th In ^¬ flow direction behind the edge 305, a radially inner angeord- designated convex curvature 306 of the flow channel 302 of the Kom ^¬ pressors is arranged. This is a one ^¬ Windwärts curvature in the direction of the axis of rotation of the engine 308 ^¬ factory. In the flow direction behind the curvature 306 is a radially outward convex curve 307 of the flow channel 302. The main exit direction of the nozzle (s) (not shown in Figure 3) may preferably include an angle with the rotational axis 308 of the engine that is between the angles β and α; where β is the angle between the rotational axis 308 of the engine and a first straight line 310, which is arranged as a tangent to the front in the flow ^¬ direction, radially inwardly disposed convex curvature 306 (at point Bi) of the flow channel of the compressor and at the downstream thereof radially outwardly disposed convex curve 307 (at point B ₂ ) of the flow channel 302; and wherein α is the angle between the rotation axis 308 of the engine and ei ^¬ ner second straight line 311, which is arranged as a tangent to the radially au- SEN arranged edge 305 of the inlet 303 of the compressor 304 (at point P) and the in flow direction behind , radially inwardly disposed convex curvature 306 (at point A) of the flow channel extends. Further, the outlet (not shown) nozzle in a radial can distance from the rotational axis 308 of the engine angeord ^¬ net to be formed between the radial distances (x _m ± _n, x _ma x) of the intersection points (x _2, x i) of the first and second straight line with that radial plane 309 in which the outlet of the nozzle (not shown in Fig. 3) is arranged.

Claims

claims

Method for cleaning a jet engine with a cleaning ^medium which contains solids which are introduced into the engine with at least one nozzle (107) by means of a carrier gas, characterized by the following features: a) the pressure of the carrier gas is 1 to 5 bar ^¬ preferably 2 to 4 bar, b) of the outlet (109) of the at least one nozzle (107) is arranged at a radial distance from the rotational axis of the engine, of the 0.6 to l, 2fa- chen the radius of the upstream facing inlet ^¬ c) the main exit direction of the nozzle (107) encloses with the axis of rotation of the engine at an angle of 10 to 30 °, preferably 12 to 25 °, more preferably 16 to 19 °.

A method according to claim 1, characterized in that the outlet (109) of the at least one nozzle (107) is arranged at a radial distance from the axis of rotation of the engine, which corresponds to 0.6 to l times the radius of the upstream inlet opening of the first compressor stage.

Method according to one of claims 1 or 2, characterized by the following features: the main exit direction of the at least one nozzle (107) forms an angle with the axis of rotation of the engine which lies between β and α; where ß is the angle between the axis of rotation of the

Engine and a first straight line, which runs as a tangent to the front, in the flow direction, radially inwardly disposed convex curvature of the flow channel of the compressor and arranged in the flow direction behind it, radially outwardly disposed convex curvature of the flow channel; α is the angle between the rotational axis of the engine and a second straight line, which runs as a tangent to the radially outer edge of the inlet of the compressor and at the downstream arranged radially inwardly disposed convex curvature of the flow channel; the exit (109) of the at least one nozzle (107) is located at a radial distance from the axis of rotation of the engine lying between the radial distances of the intersections of the first and second straight lines with the radial plane in which the exit (109) is located.

Method according to one of claims 1-3, characterized in that the solids are selected from the group consisting of solid carbon dioxide and What ^¬ sereis.

A method according to claim 4, characterized in that the carbon dioxide and / or water ice in the form of pellets or in any other form is crushed and used.

6. The method according to claim 4 or 5, characterized in that the cleaning medium solid carbon dioxide and Water ice in a mass ratio of 5: 1 to 1: 5, preferably ^¬ 1: 2 to 2: 1.

Method according to one of claims 4 to 6, characterized in that the solid carbon dioxide and / or the water ice a pellet size of 1 to 10 mm, preferably ^¬ 3 to 6 mm ago.

Method according to one of claims 1 to 7, characterized in that the solids with a mass ^¬ flow of 100 to 2000 kg / h, preferably 200 to 1500 kg / h, more preferably 350 to 2000 kg / h, more preferably 400 to 2000 kg / h, more preferably 350 to 1200 kg / h, more preferably 400 to 1200 kg / h, more preferably 100 to 600 kg / h, further preferably 200 to 500 kg / h, further preferably 350 to 450 kg / h are introduced ,

Method according to one of claims 1 to 8, characterized in that the cleaning of the jet engine (50) over a period of 1 to 15 minutes, preferably 2 to 10 minutes, more preferably 4 to 8 minutes is performed.

Method according to one of claims 1 to 9, characterized in that during a cleaning process, 1.5 to 200 kg, preferably 35 to 200 kg, more preferably 40 to 200 kg, more preferably 40 to 120 kg, more preferably 1.5 to 50 kg, further preferably ^¬ 3 to 35 kg, more preferably 7 to 25 kg of solids are introduced into the engine.

11. The method according to any one of claims 1 to 10, characterized in that the at least one nozzle (107) is a flat jet nozzle.

12. The method according to any one of claims 1 to 11, characterized in that the jet engine with a fan speed of 50 to 500 min ^-1 , preferably 100 to 300 min ^-1 , more preferably 120 to 250 min ^{-1 is allowed to} rotate.

13, nozzle means with at least one nozzle (107), the substances is for introducing the cleaning medium comprising hard ^¬ formed in a jet engine, having means for the rotationally fixed connection with the shaft of the turbofan jet engine, and which comprises a rotary coupling (105) to which is a Lei ^¬ tung connection connectable, characterized in that the lines (108) to guide the cleaning medium from the rotary coupling (105) to the nozzles (107) are formed such that a solid of

Flow can follow unhindered and does not precipitate or sublime on the pipe walls.

14. Nozzle device with at least one nozzle, which is designed to introduce cleaning medium containing solids into a jet engine, the means for non-rotatable connection with the shaft of the turbofan ei ^¬ nes jet engine having, and a Drehkupp ^¬ ment (105), to the a line connection can be connected, characterized in that the connection of the nozzle-side outlet (106) of the rotary joint (105) with the inlet of the at least one nozzle (107) by means of a flexible hose (108) he follows ^¬ .

15. Nozzle device according to claim 14, characterized in that the nozzle-side outlet (106) of

Rotary coupling (105) diametrically opposite the inlet (110).

16. Nozzle device according to one of claims 13 to 15, characterized in that the rotary coupling of the means for non-rotatable connection with the shaft of the turbo fan of a jet engine 0.2 to 2 m, preferably 0.5 to 2 m, more preferably 0 , 75 to 1.25 m apart.

17. Nozzle device according to one of claims 13 to 16, characterized in that the guide of the cleaning ^¬ tion medium from the inlet of the at least one nozzle to the nozzle outlet is formed substantially straight.

18. Nozzle device according to one of claims 13 to 17, characterized in that it is designed for introducing the cleaning medium in the compressor stages of the jet engine.

19. Nozzle device according to one of claims 13 to 18, characterized in that it comprises at least one nozzle (107).

20. Nozzle device according to one of claims 13 to 19, characterized in that it has flat jet nozzles ^¬ .

21, the nozzle device according to any one of claims 13 to 20, characterized in that the radial distance of the SI ^¬ senaustritts of the axis of rotation of the engine 200 to 800 mm, preferably 400 to 750 mm, more before ^¬ preferably 600 to 700 mm, more preferably from 200 to 400 mm, preferably 230 to 300 mm, more preferably ^¬ 260 to 280 mm.

22. Nozzle device according to one of claims 13 to 21, characterized in that the jet plane a Angle with the axis of rotation of the jet engine includes, which is preferably 10 to 30 °, further preferably ^¬ 12 to 25 °, more preferably 16 to 19 °.

Nozzle device according to one of Claims 13 to 22, characterized by the following features: the jet plane encloses an angle with the axis of rotation of the jet engine which lies between β and α; where ß is the angle between the axis of rotation of the

Engine and a first straight line, which runs as a tangent to the front, in the flow direction, radially inwardly disposed convex curvature of the flow channel of the compressor and arranged in the flow direction behind it, radially outwardly disposed convex curvature of the flow channel; α is the angle between the axis of rotation of the engine and a second straight line, which runs as a tangent to the radially outer edge of the inlet of the compressor and arranged in the flow direction behind it, radially inwardly disposed convex curvature of the flow channel.

Arrangement comprising a jet engine and a nozzle device according to any one of claims 13 to 23, characterized in that the nozzle device is arranged so that its nozzle (s) (107) are directed towards the inlet of the jet engine, so that the cleaning medium in the Jet engine can get. Arrangement according to claim 24, characterized in that the main exit direction of the at least one nozzle (107) with the axis of rotation of the jet engine at an angle of 10 to 30 °, preferably 15 to 25 °, more preferably 16 to 19 °.

Arrangement according to claim 24 or 25, characterized in that the outlet of the at least one nozzle (107) is arranged at a radial distance from the axis of rotation of the engine, which is 0.5 to l, 2fach, preferably 0.5 to hach , the radius of the upstream inlet opening of the first compressor stage corresponds.

Arrangement according to one of claims 24 to 26, characterized by the following features: the main exit direction of the at least one nozzle (107) includes with the axis of rotation of the jet power plant ^¬ an angle which lies between α and ß; where ß is the angle between the axis of rotation of the

Engine and a first straight line, which runs as a tangent to the front, in the flow direction, radially inwardly disposed convex curvature of the flow channel of the compressor and arranged in the flow direction behind it, radially outwardly disposed convex curvature of the flow channel; α is the angle between the rotational axis of the engine and a second straight line which is tangent to the radially outer edge of the inlet of the compressor and downstream thereof arranged, radially inwardly disposed convex curvature of the flow channel extends; the exit (109) of the at least one nozzle (107) is located at a radial distance from the axis of rotation of the engine lying between the radial distances of the intersections of the first and second straight lines with the radial plane in which the exit (109) is located.

Arrangement according to one of claims 24 to 27, characterized by the following features: a) the nozzle device is non-rotatably connected to the shaft of the turbofan of the jet engine; b) the axes of rotation of the turbofan of the jet drive ^¬ plant and the nozzle device are arranged substantially concentric; c) the nozzles (107) of the nozzle device have a radial distance from the common axis of rotation of the jet engine and the Düsenein ^¬ direction, which is 0.5 to l, 2 times, preferably ^¬ 0.5 to lfache the radius of the inlet opening of the first compressor stage; d) the outlet openings (109) of the nozzles (107) are arranged in the axial direction behind the plane of the turbo fan and / or the nozzles (107) are arranged in the interstices of the blades of the turbo fan and / or aligned with spaces of the blades of the turbo fan, so that the jet streams are substantially unhindered can pass through the plane of the turbofan.