EP3189934A1 - Device for cleaning a jet engine - Google Patents

Abstract

The invention relates to a nozzle device with at least one nozzle (107), which is designed for introducing cleaning medium containing solids in a jet engine having means for non-rotatable connection with the shaft of the turbofan of a jet engine, and having a rotary coupling (105) a line connection can be connected. According to the invention, the lines (108) for guiding the cleaning medium from the rotary coupling (105) to the nozzles (107) are designed such that a solid can follow the flow unhindered and does not precipitate or sublime at the tube walls. Another object of the invention is a correspondingly designed arrangement of such a nozzle device and an engine.

Description

The invention relates to a device, an arrangement and a method for cleaning an aircraft jet engine.

Aircraft jet engines have one or more compressor stages, a combustor, 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 powered by the turbine stages and allows a significant portion of the air passing through the engine as a so-called secondary air flow to bypass the compressor stages, combustor and turbine stages. By such a side stream, the efficiency of an engine can be significantly increased and also provided for improved noise reduction of the engine.

Contamination of an aircraft jet engine can lead to a reduction in efficiency, resulting in increased fuel consumption and thus increased environmental impact. The pollution can be caused for example by insects, dust, salt spray or other environmental pollution. Parts of the engine can be contaminated by combustion residues of the combustion chamber. These contaminants form a coating on the air-flowed parts of an aircraft engine and affect the surface quality. This affects the thermodynamic efficiency of the engine. In this case, in particular, the blades in the compressor stages are mentioned whose pollution has a significant impact on the efficiency of the entire engine.

To eliminate impurities is known to clean an engine with a cleaning liquid, usually hot water. From the WO 2005/120953 An arrangement is known in which a plurality of cleaning nozzles 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. The cleaning fluid introduced into the engine is intended to wash away contaminants 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 coal dust is introduced as the water through nozzles in the engine and removes contaminants from surfaces due to abrasive effects. However, the coal dust also attacks the surface of the engine parts, which is why a cleaning medium such as coal dust is not suitable for the regular cleaning of aircraft engines. In addition, when cleaning with coal dust remain unwanted remains of the cleaning material in the engine.

WO 2009/132847 A1 discloses an apparatus and method for cleaning jet engines using solid carbon dioxide as the cleaning medium.

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

This object is achieved by a nozzle device according to claim 1 or 2 and an arrangement according to claim 12. Advantageous developments emerge from the dependent claims.

The invention also relates to a method for cleaning a jet engine with a cleaning medium containing solids. The solids are introduced by means of a carrier gas through at least one nozzle in the engine. The cleaning medium according to the invention thus comprises at least one carrier gas and solids, preferably exclusively 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 in the rearmost stages. According to the invention, in particular, it is achieved that thermolabile solids such as, in particular, carbon dioxide or ice do not already release and / or sublimate or melt all kinetic energy in the front stages of the compressor. 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 according to the invention 1 to 5 bar, preferably 2 to 4 bar. A particularly preferred pressure is 3 bar.

In order to allow the desired entrainment of the solids by the air flow in the compressor without the solids abutting against the inner or outer compressor wall prematurely, the exit direction of the nozzle (in the context of the invention this term denotes the main exit direction) should extend as far as possible into the compressor, without this exit direction or its imaginary axis touching the walls of the compressor. To this end is provided according to the invention that the outlet of the at least one nozzle is arranged at a radial distance from the axis of rotation of the engine, which corresponds to 0.5 to 1.2 times, preferably 0.5 to 1 times the radius of the upstream inlet opening of the first compressor stage. The outlet thus lies in the radial direction closer to the outer compressor wall than at the rotational axis of the engine or compressor. The main exit direction of the nozzle according to the invention is directed obliquely inwards towards the axis of rotation of the engine and includes with this axis an angle of 10 to 30 °, preferably 12 to 25 °, more preferably 16 to 19 °.

The combination of these process parameters according to the invention allows effective cleaning of the compressor (core engine) of jet engines over their entire length, in particular in the rear stages in the flow direction.

A compressor geometry which is particularly preferred in the context of the invention has a curved flow channel, with a convex curvature of the flow channel arranged radially inwardly and a convex curvature of the flow channel arranged radially outwardly in the flow direction behind it. 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 for this compressor geometry Advantageous variant of the method according to the invention, the main exit direction of the at least one nozzle with the axis of rotation of the engine preferably include an angle which is between β and α; where β is the angle between the axis of rotation of the engine and a first straight line extending as a tangent to the upstream, radially inwardly disposed convex curvature of the flow channel of the compressor and to the radially outwardly disposed convex curvature of the flow channel; and 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 (compressor) and arranged on the radially inwardly disposed convex curvature of the flow channel. Furthermore, the outlet of the at least one nozzle can preferably be arranged at a radial distance from the axis of rotation of the engine, which lies between the radial distances of the intersections of the first and second straight lines with the radial plane in which the outlet of the at least one nozzle is arranged. In the context of the invention, the term radial plane denotes a plane arranged perpendicular to the axis of rotation.

According to the invention, the solids are preferably selected from the group consisting of solid carbon dioxide and water ice. Particularly preferred is solid carbon dioxide. Carbon dioxide and / or water ice can be used particularly preferably 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 from liquid carbon dioxide solid carbon dioxide pellets or solid carbon dioxide snow, and this transported with the carrier gas to the nozzle device. In both cases, the solid carbon dioxide exits the nozzles of the nozzle device and enters the engine to be cleaned. The document "Carbon Dioxide Blasting Operations" of the US Armed Forces describes the technology for the production of CO ₂ pellets. Pellets are recovered, for example, by densification of solid CO ₂ (eg flakes) in a pelletizer or the like. The production of ice-cream pellets (water ice) is familiar to the person skilled in the art and needs no further explanation here.

In a variant of the method according to the invention, the cleaning medium may comprise solid carbon dioxide and water ice in a mass ratio of 5: 1 to 1: 5, preferably 1: 2 to 2: 1. Basically, it is already known ( WO 2012/123098 A1 ) to provide a mixture of pellets of carbon dioxide and ice as a solid abrasive for cleaning surfaces. 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 cleans on the one hand by the kinetic energy of the collision and by thermal effects , Due to the induced by the carbon dioxide heat-cold voltage impurities of detached from the surfaces of the engine parts. The ice added according to the invention in the mixture has a higher hardness and a longer shelf life than solid carbon dioxide. Thus, it improves the mechanical cleaning effect by the kinetic energy of the impact and is better able to penetrate the compressor as a whole up to the rear stages and also there to develop a cleaning effect. The mixture used according to the invention on the one hand causes a substantially complete and uniform cleaning of all stages of the compressor and contributes to the other only relatively small amounts of water in the engine. This registered water is for the most part transported away 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 1 to 10 mm, preferably it may be about 3 mm. If elongated pellets are used, their length may be, for example, 3 to 6 mm, the dimension transverse to the longitudinal extent, 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. The duration of the cleaning process (pure beam time without pauses) is preferably 1 to 15 minutes, more preferably 2 to 10 min, more preferably 4 to 8 min. Thus, for example, during a cleaning operation, 1.5 to 200 kg, preferably 35 to 200 kg, more preferably 40 to 200 kg, more preferably 40 to 120 kg, further preferably 1.5 to 50 kg, further preferably 3 to 35 kg, on preferably 7 to 25 kg of solids are introduced into the engine.

Preferably, the nozzle or the nozzles are flat jet nozzles, for example flat jet 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 . Particularly preferred 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 relates to a nozzle device with at least one nozzle, which is designed for introducing cleaning medium containing solids in a jet engine having means for non-rotatable connection with the shaft of the turbofan of a jet engine, and having a rotary coupling to which a line connection can be connected is.

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 basic idea connecting both variants of the invention is that the lines for the cleaning medium from the rotary coupling to the outlet of the nozzle have as gentle and not too large transition angles or angles of curvature as possible in order to convey the solids as low as possible by means of the carrier gas. In the second variant of the invention, the use of preferably removable tubes by their flexibility allows a sufficiently gently curved guiding of the solids. On the other hand, the hoses ensure that the nozzle device for storage and transport is sufficiently small and not too bulky, in particular for transport and storage, the hoses can preferably be disassembled and transported separately or stored.

A line connection connects the nozzle device with a supply device, this supply device provides the cleaning medium available (for example, in tanks) and can be provided with operating and drive means, pumps, energy storage or the like be. It is preferably designed as a mobile, in particular mobile unit.

The nozzle device has one or more nozzles. It is particularly preferred if the nozzle device has at least two nozzles.

The non-rotatable connection with the shaft allows the nozzle device to be dry -ranked, i. during slow spin of the engine without injection of kerosene, co-rotate.

The term rotary coupling between the nozzle device and the line connection is to be understood as meaning 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 interstices of the blades of the turbo fan directly to the first compressor stage.

Preferably, the nozzle-side outlet of the rotary coupling is located diametrically opposite the inlet. The inlet preferably has in the axial direction and upstream, ie in the direction from which takes place in the mounted state of the nozzle device on an engine, the Anstrom 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 nozzle device according to the invention, the nozzle or the nozzles are generally arranged in the radially outer region, while the rotary coupling is usually arranged in the axis of rotation or axis of rotation. In order to allow a guide of the cleaning medium through lines or flexible hoses with small curvatures, it is advantageous if the rotary coupling, which usually represents the upstream axial end of the nozzle device, of the means for non-rotatable connection with the shaft of the turbo fan, which usually represent the downstream end of the nozzle device according to the invention, having a sufficiently large axial distance, which allows or facilitates a guidance of the lines from the rotary joint to the nozzles 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 is attached to the turbo fan so that their nozzles point between the 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 upstream in the flow direction and the spray direction of the cleaning medium can 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 device has at least two or more nozzles, which are preferably distributed rotationally symmetrically about the axis of rotation. The nozzles are preferably designed as flat jet nozzles, which may preferably have, for example, an opening angle of 1 °.

The radial distance of the nozzle outlet from the rotational 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, further 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, for example, is suitable for cleaning the core engine of a CF6-50 engine. The preferred distance of 600 to 700 mm, for example, is suitable for cleaning the core engine of a CF6-80 engine. When mounted nozzle device, the nozzle outlet is then in the region of the radially outer edge of the inlet of the compressor.

The jet plane or main exit direction of the nozzle (s) is preferably directed obliquely inwards towards the axis of rotation of the engine and includes with this axis an angle of 10 to 30 °, preferably 12 to 25 °, more preferably 16 to 19 °. The values mentioned can vary depending on the drive to be cleaned and should be selected so that the main exit direction of the nozzle (or its imaginary extension) protrudes as far as possible into the compressor, without touching inner or outer walls of the compressor.

In a preferred embodiment, the jet plane or main exit direction of the nozzle (s) with the axis of rotation of the engine may preferably include an angle which is between β and α; where β is the angle between the axis of rotation of the engine and a first one Straight line, which runs as a tangent at the front in the flow direction, radially inwardly disposed convex curvature of the flow channel of the compressor and at the flow direction downstream, arranged radially outwardly convex curvature of the flow channel; and 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 (compressor) and arranged on the radially inwardly disposed convex curvature of the flow channel.

The means for non-rotatable connection to the shaft of the turbofan turbofan preferably includes attachment means for attachment to the turbine blade vanes, 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 device may have a device for essentially positive placement on the shaft hub of the fan for rotationally fixed fixation with the shaft of the turbofan. 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 appropriate means for non-rotatable 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. It does not mean, that the entire surface of the shaft hub must be positively enclosed.

For example, the device may have one or more ring parts, with which it can be placed on the shaft hub. In a plurality of ring parts, these have a different diameter, which is adapted to the diameter of the shaft hub in the corresponding 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 fastened (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 can be provided that the carrier gas to cool, so that ice pellets and / or carbon dioxide pellets in the carrier gas stream are as stable as possible. Alternatively, however, it is also possible to heat the carrier gas stream, for example to about 80 ° C. This seems absurd, for example, for carbon dioxide pellets, 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 that by excessive cooling, the solid carbon dioxide can only develop an insufficient cleaning effect (due to the 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. Since the carrier gas only acts on the cold pellets over a very short period of time before they can unfold their cleaning effect, the influence of the heated carrier gas on the pellets is not or barely significant.

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 engine and includes with this axis an angle of 10 to 30 °, preferably 12 to 25 °, more preferably 16 to 19 °.

Preferably, the outlet of the at least one nozzle is arranged at a radial distance from the rotational axis of the engine, which corresponds to 0.5 to 1.2 times, preferably 0.5 to 1 times the radius of the upstream inlet opening of the first compressor stage. The outlet thus lies in the radial direction closer to the outer compressor wall than at the rotational axis of the engine or compressor.

In a preferred embodiment, the main exit direction of the nozzle (s) may include an angle with the rotational axis of the engine that is between β and α; where β is the angle between the axis of rotation of the engine and a first straight line extending as a tangent to the upstream, radially inwardly disposed convex curvature of the flow channel of the compressor and to the radially outwardly disposed convex curvature of the flow channel; and 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 (compressor) and arranged on the radially inwardly disposed convex curvature of the flow channel. Furthermore, the outlet of the at least one nozzle can preferably be arranged at a radial distance from the axis of rotation of the engine, which lies between the radial distances of the intersections of the first and second straight lines with the 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 1.2 times, preferably the 0, 5 to 1 times the radius of the first compressor stage, and the outlet openings of the nozzles arranged in the axial direction behind the plane of the turbofan and / or the nozzles are arranged in the interstices of the turbofan blades and / or aligned with spaces of the turbofan blades, so that the nozzle jets substantially can pass through the plane of the turbo fan unhindered.

Fig. 1

eine erste Ansicht einer erfindungsgemäßen Düseneinrichtung;

Fig. 2

eine zweite Ansicht einer erfindungsgemäßen Düseneinrichtung;

Fig. 3

eine Ansicht einer besonders bevorzugten Kompressorgeometrie.

An embodiment of the invention will be explained below with reference to the drawings. Show:

Fig. 1

a first view of a nozzle device according to the invention;

Fig. 2

a second view of a nozzle device according to the invention;

Fig. 3

a view of a particularly preferred compressor geometry.

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. For the details of the connection of the nozzle device with a shaft hub will be on the WO 2009/132847 A1 reference, the disclosure of which is also incorporated herein by reference. The two ring elements 101, 102 are connected to each other 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 rotary joint 105 may alternatively be formed separately from the branch with the pressure ports 106 and, for example, be connected thereto by a short length of hose, the flexibility of which compensates for possible axial deviations during assembly. From this rotary coupling 105 extend two axially downstream leading pressure ports 106. To the pressure ports 106, two pressure hoses 108 can be connected (in Fig. 1 For the sake of clarity, only one pressure hose 108 is shown), whose respective other end is connected to the inlet of the flat jet nozzles 107.
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 promotion 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 is in the exemplary embodiment about 1.2 m. This distance is sufficient that the pressure hoses 108, the inlets of the nozzles 107 without too large curvatures of these pressure hoses 108 with the outlets 106th 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 main exit direction of the nozzles 107 (which corresponds essentially to their longitudinal axis) encloses an angle of 18 ° with the axis of rotation of the nozzle device.

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

To clean a jet engine, the nozzle device is placed on the shaft hub of the turbo fan and fixed to the blades of the turbo fan. The engine is rotated (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. Shown are a turbo fan blade 301 and the downstream inlet 303 of the compressor 304 relative to the axis of rotation 308 of the engine. The inlet 303 has a radially outer edge 305. In the flow direction behind the edge 305, a radially inwardly disposed convex curvature 306 of the flow channel 302 of the compressor is arranged. This is an inward curvature in the direction of the axis of rotation 308 of the engine. In the flow direction behind the curvature 306 is a radially outwardly disposed convex curvature 307 of the flow channel 302. The main exit direction of the nozzle (s) (in Fig. 3 not shown) 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 arranged as a tangent to the upstream, radially inwardly disposed convex curve 306 (at point B ₁ ) of the flow channel of the compressor and downstream therefrom, radially outwardly disposed convex curvature 307 (at point B ₂ ) of the flow channel 302 extends; and α is the angle between the rotational axis 308 of the engine and a second straight line 311 arranged as a tangent to the radially outer edge 305 of the inlet 303 of the compressor 304 (at point P) and radially inward of the upstream flow direction convex curve 306 (at point A) of the flow channel. Further, the exit of a nozzle (not shown) may be located at a radial distance from the axis of rotation 308 of the engine between the radial distances (x _min , x _max ) of the intersection points (x ₂ , x ₁ ) of the first and second straight lines with the radial plane 309 lies in the outlet of the nozzle (in Fig. 3 not shown) is arranged.

Claims (16)

Nozzle device with at least one nozzle (107), 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 (105) to which a line connection can be connected characterized in that the conduits (108) for guiding the cleaning medium from the rotary joint (105) to the nozzles (107) are formed such that a solid can follow the flow unhindered and does not precipitate or sublime at the pipe walls. 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 (105) to which 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). Nozzle device according to claim 2, characterized in that the nozzle-side outlet (106) of the rotary coupling (105) is diametrically opposed to the inlet (110). Nozzle device according to one of claims 1 to 3,
characterized in that the rotary coupling of the means for non-rotatable connection with the shaft of the Turbofans a jet engine 0.2 to 2 m, preferably 0.5 to 2 m, more preferably 0.75 to 1.25 m is spaced apart. Nozzle device according to one of claims 1 to 4,
characterized in that the guidance of the cleaning medium from the inlet of the at least one nozzle to the nozzle outlet is formed substantially rectilinear. Nozzle device according to one of claims 1 to 5,
characterized in that it is designed for introducing the cleaning medium in the compressor stages of the jet engine. Nozzle device according to one of claims 1 to 6,
characterized in that it comprises at least one nozzle (107). Nozzle device according to one of claims 1 to 7,
characterized in that it comprises flat jet nozzles. Nozzle device according to one of claims 1 to 8,
characterized in that the radial distance of the nozzle exit from the rotational axis of the engine 200 to 800 mm, preferably 400 to 750 mm, more preferably 600 to 700 mm, more preferably 200 to 400 mm, preferably 230 to 300 mm, more preferably 260 to 280 mm is. Nozzle device according to one of claims 1 to 9,
characterized in that the beam plane at an angle with the axis of rotation of the jet engine which is preferably 10 to 30 °, more preferably 12 to 25 °, further preferably 16 to 19 °. Nozzle device according to one of claims 1 to 10, characterized by the following features: the jet plane encloses with the axis of rotation of the jet engine an angle which lies between β and α;
in which 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; 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 of a jet engine and a nozzle device according to one of claims 1 to 11, characterized in that the nozzle device is arranged so that its nozzle (s) (107) are directed to the inlet of the jet engine, so that the cleaning medium reach the jet engine can. Arrangement according to claim 12, 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 12 or 13, 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 1.2 times, preferably 0.5 to 1 times, of the Radius of the upstream inlet opening of the first compressor stage corresponds. Arrangement according to one of Claims 12 to 14, 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 jet engine which lies between β and α;
in which 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; 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 12 to 15, characterized by the following features: a) the nozzle device is rotatably connected to the shaft of the turbo fan of the jet engine; b) the axes of rotation of the turbo fan of the jet engine and the nozzle device are arranged substantially concentrically; c) the nozzles (107) of the nozzle means are at a radial distance from the common axis of rotation of the jet engine and the nozzle means which is 0.5 to 1.2 times, preferably 0.5 to 1 times 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.

Images