Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
  • F01D19/00—Starting of machines or engines; Regulating, controlling, or safety means in connection therewith
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
  • F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
  • F02C7/26—Starting; Ignition
  • F02C7/262—Restarting after flame-out
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
  • F02C3/00—Gas-turbine plants characterised by the use of combustion products as the working fluid
  • F02C3/14—Gas-turbine plants characterised by the use of combustion products as the working fluid characterised by the arrangement of the combustion chamber in the plant
  • F02C3/16—Gas-turbine plants characterised by the use of combustion products as the working fluid characterised by the arrangement of the combustion chamber in the plant the combustion chambers being formed at least partly in the turbine rotor or in an other rotating part of the plant
  • F02C3/165—Gas-turbine plants characterised by the use of combustion products as the working fluid characterised by the arrangement of the combustion chamber in the plant the combustion chambers being formed at least partly in the turbine rotor or in an other rotating part of the plant the combustion chamber contributes to the driving force by creating reactive thrust
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
  • F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
  • F02C7/26—Starting; Ignition
  • F02C7/268—Starting drives for the rotor, acting directly on the rotor of the gas turbine to be started
  • F02C7/27—Fluid drives
  • F02C7/272—Fluid drives generated by cartridges
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
  • F42B10/00—Means for influencing, e.g. improving, the aerodynamic properties of projectiles or missiles; Arrangements on projectiles or missiles for stabilising, steering, range-reducing, range-increasing or fall-retarding
  • F42B10/32—Range-reducing or range-increasing arrangements; Fall-retarding means
  • F42B10/48—Range-reducing, destabilising or braking arrangements, e.g. impact-braking arrangements; Fall-retarding means, e.g. balloons, rockets for braking or fall-retarding
  • F42B10/54—Spin braking means
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
  • F42B3/00—Blasting cartridges, i.e. case and explosive
  • F42B3/04—Blasting cartridges, i.e. case and explosive for producing gas under pressure
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2260/00—Function
  • F05D2260/85—Starting

Definitions

• the present invention relates to the field of rotary pyrotechnic actuators, in particular for application to rotating machines, for example the start-up of turbomachines. It relates more particularly to an emergency starting system for carrying a turbomachine to its nominal operating speed in a limited period of time.
• State of the art :
• one or more engines can be cut according to the power demand during certain phases of flight. It may then be necessary to restart them urgently, for an unforeseen maneuver or because of an engine failure.
• a main starting system often an electric starter, allows the engine to start during ordinary and repetitive conditions of use.
• This main starting system does not generally achieve the rated speed in the time required in case of emergency.
• pyrotechnic hot gas generators In order to concentrate the power required for rotating the turbomachine in a short time, systems dedicated to emergency starting can use pyrotechnic hot gas generators. This is the case of systems, such as that described in FR2862749, which inject the hot gases into the primary circuit so that they relax in the high pressure turbine rotating the whole of the turbomachine.
• the end of the start sequence corresponds to the ignition of the combustion chamber, supplied with air and fuel, which allows the turbine engine to take the relay with the desired power.
• a pyrotechnic starter using this principle can be simple in design and is well suited for single-use applications, such as a missile.
• By against the hot gases from the combustion of the propellant can have a negative impact on the mechanical strength of the hot parts of the turbomachine downstream of their injection ports.
• these openings must be equipped with a shutter which closes at the end of emergency start, if the starter is decoupled from the vehicle after use.
• emergency starting systems can use the high-energy gases from the pyrotechnic gas generator to drive a turbine or a positive displacement motor, such as that described in FR299004, in order to drive the turbomachine in rotation.
• a transmission incorporating a gear train adapts the rotational speed of the starter to that of the turbomachine.
• a permanent rotation of the system will cause an aging of the starter even if it is not in function and consumes energy by mechanical or aerodynamic friction in the starter motor running empty.
• This type of starter must therefore be decoupled from the turbine engine when it is not in use, by a disengaging or freewheel system, in the case of a turbine.
• the object of the invention is to propose an emergency starting system for a turbomachine exploiting the advantages of a pyrotechnic gas generator while avoiding the drawbacks noted on the known solutions concerning their size, their complexity or their impact on the engine. wear of the turbomachine, for their permanent installation.
• the problem of rotating rotating machines to quickly reach a nominal speed relates to other applications.
• the invention therefore seeks a quick start system easy to integrate on a rotating machine and independent of its mode of operation.
• other applications of this pyrotechnic rotary actuator requiring a high power density in a short period of time can also be envisaged, such as, for example, an additional point motorization.
• the invention relates to an emergency starting system for a turbomachine, characterized in that it comprises a reel for driving the turbomachine, said reel comprising a drum integral with a rotation shaft, the axes of symmetry of the drum and of the shaft being merged, the reel further comprising at least one gas ejection nozzle placed at the periphery of the drum and oriented substantially tangentially with respect to the rotation about said axis, and a pyrotechnic device for generating gas embedded in the reel and supplying said at least one nozzle, said emergency starting system further comprising a support in which the reel shaft rotates and a gas recovery volute radially surrounding the reel, integral with said support.
• the nozzles produce jets of tangential gas ejections which make it possible to create a torque on the shaft of the reel.
• the system can thus be used to drive a turbomachine by coupling its shaft to the input gear of the latter.
• the pyrotechnic device makes it possible to generate gases in a chamber upstream of the nozzles at a high pressure and a high temperature thus creating the thrusts and therefore the torques necessary to drive a turbomachine up to at speeds corresponding to its nominal operating speed.
• This pyrotechnic device is embedded in the reel reduces transfer problems and losses during its operation.
• the principle of the reel means that it can be set to work on the turbomachine and that it can drive it in rotation during its normal operation, when the emergency starting system is not engaged. Indeed, the reel creates little friction losses and is not likely to be worn prematurely.
• the gas generating device comprises a solid propellant block. This facilitates the maintenance of the device. Thus, it is conceivable to easily replace the pyrotechnic device after use.
• the gas generating device comprises a combustion chamber which supplies said at least one nozzle and which is formed in the solid propellant block.
• said at least one nozzle may be a two-dimensional nozzle. This allows the reel to be designed more compact and easier to produce.
• the reel having a direction of rotation defined by the orientation of the nozzles
• the volute has an opening on an angular sector around the axis of rotation of the reel and the section of the vein of the volute evolves by turning according to the direction of rotation of the reel from one edge to the other of the angular sector complementary to the angular sector of the opening.
• the shape of the volute is involved in the relaxation of the gases leaving the nozzles and therefore via the thrust thereof, the torque delivered by the reel. It is therefore important to optimize the shape.
• this shape makes it possible to evacuate radially with respect to the axis, the hot gases leaving the nozzles by limiting the heating of the equipment surrounding the reel.
• the emergency starting system comprises an ignition means of the pyrotechnic device for generating gas that can be placed in armed or disarmed mode.
• the invention also relates to a turbomachine comprising a system according to the invention, and comprising a shaft and a transmission means coupling the shaft of the reel to the shaft of the turbomachine, the support being held fixed relative to a housing of the means. of transmission. Since the reel operates independently of the turbomachine, it can be placed outside, for example fixed to the accessory table cover, and the turbomachine can be protected from the influence of ejection gases.
• the turbomachine further comprising an outlet nozzle
• the volute can lead into a pipe bringing the gas expanded in said exhaust nozzle of the turbomachine.
• the pyrotechnic starter can also be mechanically coupled to a main starting system of said turbomachine.
• Figure 1 shows a perspective view of a reel of a starter system according to the invention.
• Figure 2 shows a section of a half-reel of a starter system according to the invention, in a plane perpendicular to the axis of rotation and passing through the nozzles.
• Figure 3 shows a longitudinal section of an emergency starting system according to the invention before use.
• Figure 4 schematically shows a perspective view of an arrangement of the gas evacuation means on an emergency starting system according to the invention.
• Figure 5 schematically shows a section, in a plane perpendicular to the axis of rotation, the gas evacuation scroll and the reel of a system according to the invention.
• Figure 6 shows a longitudinal section of an emergency starting system according to the invention at the beginning of its ignition.
• Figure 7 shows a longitudinal section of an emergency starting system according to the invention towards the end of its ignition.
• FIG. 8 shows a layout diagram on a turbomachine of an emergency starting system according to the invention.
• the invention relates to a system capable of driving a rotating shaft by creating a sufficient torque to start a turbomachine.
• This system comprises a reel 1 formed of a cylindrical drum 2 and a rotation shaft 3, integral and with the same axis LL.
• the drum 2 having a given width D along the axis of rotation LL, several nozzles 4 are arranged on a narrower band of its peripheral cylindrical wall, of width d.
• This strip is situated on one side of the cylindrical wall 5 of the drum 2.
• the band in which the nozzle 4 is located can for example be eccentric as shown, and close to the upper face 6.
• the nozzles 4 are oriented tangentially to the cylindrical wall 5, all in the same direction.
• This direction corresponds to the direction of the jet of gas that must exit and thus determines, by reaction, a rotation of the reel 1 in operation, in the opposite direction to that of the gas jet.
• the nozzles 4 are distributed uniformly in azimuth and are three in number, two being visible in FIG. Still on the example, the nozzles 4 are of two-dimensional shape. This means that they are defined by their shape in a cross-sectional plane transverse to the axis of rotation LL. With reference to FIG. 2, the nozzle 4 forms a divergent duct of length dz from a neck 8 of minimum section.
• This neck 8 is at a radius R of the axis LL of the reel 1 and the nozzle 4 is oriented along an axis ZZ substantially perpendicular to the radius passing through the neck 8.
• the axisymmetrically shaped nozzles 4 according to the required ease of sizing and fabricability. They are always defined, in this case, as a divergent duct oriented along a ZZ axis.
• the nozzle 4 is in communication through the neck 8 with a combustion chamber 9, to contain pressurized gas when the reel 1 is in operation.
• this combustion chamber 9 is common to the three nozzles 4 placed on the cylindrical wall 5 of the drum 2. It is therefore necessary a gas generator to fill the combustion chamber 9 with pressurized gas.
• FIG. 3 which shows the reel 1 before use, it can be seen that the drum 2 forms a cavity between its cylindrical wall 5 and its upper 6 and lower 7 faces.
• the inner cavity of the drum 2 is filled by a block solid 1 0 of a material defined to produce hot gases when ignited by an ignition device, placed at the level of the combustion chamber 9 but not shown in the figures.
• This material is generally solid propellant.
• the space left free in the drum 2 between the band occupied by the nozzles 4 and the lower face 7 is sized to form a sufficient reservoir of propellant whose combustion will generate gases for the time necessary for starting the turbomachine.
• the combustion chamber 9 supplying the nozzles 4, intended to receive the gases produced by the combustion of the propellant is dug in the block 1 0 of propellant and occupies a reduced space at the level of the nozzles.
• the nozzles 4 are plugged by a lid 1 1 ejected by the pressure during ignition, which prevents the introduction of dust and moisture into the combustion chamber 9.
• the reel 1 is integrated on a support 12 comprising bearings 13, 14 in which the shaft 3 rotates.
• the shaft 3 is intended to be coupled to a tree 15 driving the turbomachine.
• this shaft 15 drives the turbomachine by a gear system, not shown, to obtain by multiplication / reduction the good speed of rotation.
• It is also coupled, for example by means of splines, on the shaft 3 of the reel 1 and is designed to break if, by accident, the transmitted torque exceeds a maximum allowable value.
• the support 12 incorporates a volute 16.
• This volute 16 radially surrounds the reel 1. It is designed to allow the expansion of gases escaping from the tuyeres 4 before evacuating them. With the part of the support 12 surrounding the drum 2, it forms a duct 16 which winds around the reel 1. The inner wall of this duct 16 is open vis-à-vis the passage of the nozzles 4 to collect the gases that escape.
• the radial section of the duct formed by the volute 16 is substantially rectangular. Referring to Figure 5, the cross section of the outer wall of the volute 16 has a spiral shape around the axis LL of the reel 1.
• the width of the volute 16 along the axis LL increases in the example given here, going from A to B.
• the section of the duct formed by the volute 16 evolves (increases in the example given here) regularly between points A and B in azimuth ⁇ to accompany the expansion of the gas, according to a law Sv (cp).
• the volute 1 6 opens into a pipe 17 intended to evacuate the gases, as shown in FIGS. 4 and 5. Depending on the type of installation, these gases may be directly discharged into the atmosphere.
• the pipe 17 can be made to open into the outlet nozzle 21. This makes it possible to eject the hot gases leaving the reel 1 in an environment already designed to withstand the temperature conditions of the gases and to protect the turbomachine and take advantage of pressure conditions favorable to their ejection.
• the block 10 of propellant is fired, with reference to FIG. 6, the combustion starts in the combustion chamber 9 in its initial form, shown in FIG. 3.
• the combustion chamber 9 fills with gas under pressure and serves as a nozzle supply chamber 4 with high energy gas at given temperature conditions Ti and pressure Pi. This gas escapes through the nozzles 4, generating a thrust and thus creating a torque that puts the reel 1 in rotation at a speed ⁇ .
• the propellant is consumed and the volume of the combustion chamber 9 of the tuyeres 4 evolves in the block 10 until the complete use of the propellant. It is within the skill of those skilled in the art to determine the initial shape of the combustion chamber 9 and the initial mass of the propellant block 10 so that the pressure conditions Pi and temperature Ti of the gases in the combustion chamber 9 evolve during this process to provide the couple in a desired evolution over the time required.
• the pressure Pi is sufficiently high for each of the nozzles 4 to be initiated, with a sonic flow at the neck 8.
• Each nozzle 4 thus creates at its output section a jet of gas in the tangential direction ZZ at This jet reaches, at the outlet section Se of the nozzle 4, a high velocity Ve, whereas the pressure Pe and the temperature Te of the gases have decreased compared with those of the gases of the combustion chamber 9.
• a tangential force F also called thrust
• the torque provided by the reel 1 on the shaft 3 of rotation is the sum of the pairs for each nozzle 4 the product of this force F by the radius R of the neck 8.
• the neck 8 is attached and constituted, for example, of an abradable material, woven and stamped such as carbon / ceramic or any other device, in order to minimize the heat transfer by conduction and radiation of the hot gases to the drum 2, during the combustion of the propellant.
• an abradable material woven and stamped such as carbon / ceramic or any other device
• the configuration shown in the figures is only an example.
• the number of nozzles 4, as well as their size and their distribution in azimuth will be adapted by the skilled person depending on the torque to be supplied and the pressure of the gases available in the combustion chamber 9.
• the shape two-dimensional nozzle 4 is advantageous in terms of size for the system, it is possible to use other forms, in particular an axisymmetric shape.
• the shape of the volute 16 contributes to the efficiency of the nozzles 4 and thus the performance of the reel 1 when it is fired.
• the combustion gases ejected at the speed Ve at the pressure Pe and the temperature Te of each of the nozzles 4 continue to relax in the volute 16, while the nozzle 4 rotates inside the volute 1 6, then are evacuated to outside by the exhaust pipe 17.
• the section distribution of the volute 16 as a function of the azimuth ⁇ between points A and B, with reference to FIG. 5, is optimized to obtain a good compromise between the expansion ratio, determining the torque provided by the reel 1 , and a gas ejection temperature Te compatible with the environment of the system.
• This compromise takes into account, in particular, forced convection phenomena in the volute 16, the conduction by the attachment means of the device and the thermal radiation of the assembly.
• volute 16 helps protect the equipment surrounding the reel 1 by guiding the gas ejected by the nozzles 4 to the pipe 17.
• the protective cap 1 1 that closes each nozzle 4 as the reel 1 is not used is designed to be disintegrated during ignition under the combined effect of the pressure and the temperature of the gases from the burning of propellant. Its remains are evacuated naturally with the gases when the reel 1 starts.
• the starter system uses an electric control.
• the ignition device of the propellant block 10 not shown in the figures, already mentioned, is connected to a circular contact track 18 flush with the surface of the cylindrical wall 5 of the drum 2.
• An electric contactor 1 9 The trotter is positioned in correspondence with the contact track 18 on the support 12 to send an electric current to the ignition device.
• the contactor 19 is itself connected to a control system, not shown, which sends the current to ignite via this ignition device, the propellant in case of emergency start.
• control system of the ignition device is designed to be armed, that is to say ready to transmit a current sufficient to trigger the combustion, or be disarmed, that is to say inhibited.
• the disarmed position has the advantage of avoiding accidental ignitions.
• ignition propellant block 10 It is part of the invention to be able to use other types of ignition propellant block 10, such as a wireless link, with optical or laser means.
• an advantageous installation for a turbomachine 20 consists in fixing the support 1 2 on the accessory table casing 22, represented here in front of the turbomachine 20. This allows, as is shown in FIG. FIG. 8, of coupling the emergency pyrotechnic starter in series, on its other face, to the main starter 23 of the turbomachine.
• This main starter 23, generally electric, is used in the usual way to start normally the turbomachine 20.
• the reel 1 does not introduce any additional gear, moreover it is a small rotating part with low inertia and low aerodynamic drag. It can therefore be placed without inconvenience in series between the main starter 23 and the turbomachine 20 waiting for possible emergency use without creating significant performance losses. Thanks to these different characteristics, the principle of operation of the reel 1 as an emergency starting means of an aircraft turbomachine 20, in an installation as shown in FIG. 8, corresponds to the choice between three states described below. .
• a first state, disarmed corresponds to the case where the turbomachine 20 operates normally. It is for example used with the other turbomachines of the aircraft to provide the nominal power under the current flight conditions. In this case, the shaft 15 drives the reel 1 in rotation.
• the control system of the ignition device of the block 1 0 propellant is disarmed.
• the control system sends continuously or discontinuously at its request, a weak electrical signal to the ignition device of the block 10 propellant to detect any discontinuity on the control line. If a fault is found by the logic of this system, a fault treatment and an appropriate report are made.
• This first disarmed state also corresponds to the case where the turbomachine is in the normal starting phase. In this case, it is the main starter which rotates the reel 1 at the same time as the turbomachine 20.
• the second state corresponds to the flight conditions where the turbomachine 20 is set aside in relation to the other turbomachines of the aircraft.
• the turbomachine 20 idles and it drives the reel 1 in its rotation, or it is simply stopped.
• the ignition system of the ignition device of the propellant block 10 is in this case armed.
• the electrical connection between the switch 19 and the contact track 18 always makes it possible to detect any anomalies on the emergency starting system as well as to perform a treatment of the fault and an appropriate signaling.
• the third state, lit, corresponds to the case where an emergency start command is sent.
• the ignition control can only have an effect if the propellant block ignition system control system is armed.
• the design of the embedded system prohibits that we can go directly from the first state to the third.
• the reel 1 By following the ignition phases of the reel 1 as described in FIGS. 6 and 7, it is then the reel 1 which creates a torque and drives the turbomachine 20.
• the entire system is designed so that the rotation speed ⁇ of the reel 1 quickly reaches the necessary value for the turbomachine to provide the expected power.
• the main starter is also activated as well as the ignition system and fuel metering of the turbomachine according to laws designed to ensure its startup at the end of the operation of the reel 1.
• the emergency starting system that has been described is not limited to the configuration shown in Figure 8 or the emergency start of a turbomachine. As was mentioned at the beginning, it can, for example, serve as an additional point motorization to provide a high power density in a short period of time. It is also conceivable to design an installation using several systems according to the invention coupled to the same axis. It can thus be advantageous to manufacture a single type of system and to modulate the number of copies installed according to the power required.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Control Of Turbines (AREA)
• Automotive Seat Belt Assembly (AREA)

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• 2014
  • 2014-02-10 FR FR1451020A patent/FR3017417B1/fr active Active
• 2015
  • 2015-02-06 CA CA2938047A patent/CA2938047A1/fr not_active Abandoned
  • 2015-02-06 RU RU2016133588A patent/RU2016133588A/ru not_active Application Discontinuation
  • 2015-02-06 JP JP2016550698A patent/JP2017511857A/ja active Pending
  • 2015-02-06 WO PCT/FR2015/050290 patent/WO2015118274A1/fr active Application Filing
  • 2015-02-06 KR KR1020167023691A patent/KR20160119124A/ko not_active Application Discontinuation
  • 2015-02-06 EP EP15709221.4A patent/EP3105423A1/fr not_active Withdrawn
  • 2015-02-06 US US15/116,169 patent/US20170175643A1/en not_active Abandoned

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