METHOD FOR MONITORING THE OCCURRENCE OF FIRE IN AN ENGINE

Abstract

A method (100) for monitoring an engine (10) of an aircraft (50) supplied with dihydrogen, comprising a safety device (1) including a safety valve (2) movable between an open position in which the engine (10) is supplied with dihydrogen and a closed position in which the engine (10) is no longer supplied with dihydrogen, an engine fire detection system, a dihydrogen leak detection system (20) and an engine damage detection system, and comprising electronic circuitry (200) adapted to implement the monitoring method (100).If a lockout authorization is given and if one of three conditions A, B, and C is true, then the safety device (1) closes the safety valve (2), with: - condition A being true if an engine fire detection system (30) detects a fire, - condition B being true if a hydrogen leak detection system (20) detects a hydrogen leak, and - condition C being true if an engine damage detection system (40) detects engine damage. Figure to be published with the abbreviation: Fig. 3.

Description

Title of the invention: METHOD FOR MONITORING THE OCCURRENCE OF A FIRE IN AN ENGINE Technical field

[0001] The invention relates to the field of monitoring the occurrence of a fire in a turbomachine of an aircraft, supplied with dihydrogen. STATE OF PRIOR ART

[0002] In a known manner, a turbomachine of an aircraft comprises a plurality of fire detection sensors connected to a monitoring device (of the FDU type for fire detection unit) configured to transmit a fire alert message when a fire is detected in the turbomachine.

[0003] Upon receipt of a fire alert message, the crew must concentrate on implementing countermeasures to the fire, such as, for example, triggering fire-fighting devices or reducing the thrust of the turbomachine. Examples include documents FR3068392 and FR3052747 which describe a device and a method for fire monitoring of a turbomachine.

[0004] Such means for detecting the occurrence of a fire on a turbomachine are effective but are not suitable for a turbomachine operating with dihydrogen. Indeed, the precursor signals of a fire are not necessarily the same as for a turbomachine operating with kerosene. In addition, the use of dihydrogen requires a faster reaction on the implementation of countermeasures to the fire.

[0005] Furthermore, it is also desirable that the fire countermeasures be effective even when the fire or a hydrogen leak results from an uncontained engine failure, also called UERF (Uncontained Engine Rotor Failure).

[0006] In this context, it is desirable to provide a method for monitoring an engine of an aircraft powered by dihydrogen, which allows the implementation of an automated countermeasure in the event of detection of a risk of fire in the engine. Presentation of the invention

[0007] To this end, according to a first aspect, there is proposed a method for monitoring an engine of an aircraft supplied with dihydrogen, comprising a safety device comprising a safety valve movable between an open position in which the engine is supplied with dihydrogen and a closed position in which the engine is no longer supplied with dihydrogen, a system for detecting an engine fire, a hydrogen leak detection system and an engine damage detection system, and comprising electronic circuitry adapted to implement the monitoring method. If a lockout authorization is given and if one of three conditions A, B and C is true, then the safety device closes the safety valve, with:

[0008] - condition A is true if an engine fire detection system detects a fire,

[0009] - condition B is true if a hydrogen leak detection system detects a hydrogen leak, and

[0010] - condition C is true if an engine damage detection system detects a engine damage.

[0011] According to one embodiment, condition B is true if one of the two conditions B1 or B2 is true, with:

[0012] - condition B1 is true if a hydrogen pressure lower than a pre-set threshold determined is detected by a hydrogen leak detection system;

[0013] - condition B2 is true if at least one of the following conditions is met: a a hydrogen concentration above a predetermined threshold is detected by the hydrogen leak detection system; or a rupture of a hydrogen supply line is detected by the hydrogen leak detection system; or a pressure in the engine above a predetermined pressure is detected by the hydrogen leak detection system; or a temperature variation above a predetermined temperature variation is detected by the hydrogen leak detection system.

[0014] According to one embodiment, condition B is true if both conditions B1 and B2 are true.

[0015] According to one embodiment, condition A is true if two conditions A1 and A2 are true, with:

[0016] - condition Al is true if a fault in a fire detection loop is detected by the fire detection system;

[0017] - condition A2 is true if the fire detection system detects a fire.

[0018] According to one embodiment, condition A is true if both conditions A1 and A2 are true within a predetermined time interval.

[0019] According to another aspect, there is provided a safety device for a dihydrogen-powered engine which comprises:

[0020] - a safety valve movable between an open position in which the motor is supplied with hydrogen and a closed position in which the engine is no longer supplied with hydrogen;

[0021] - an engine fire detection system;

[0022] - a hydrogen leak detection system;

[0023] - an engine damage detection system; and

[0024] - electronic circuitry adapted to implement a monitoring method wherein, if a lockout authorization is given and if one of at least three conditions A or B or C is true, then the safety device closes the safety valve, with:

[0025] - condition A is true if an engine fire detection system detects a fire,

[0026] - condition B is true if a hydrogen leak detection system detects a hydrogen leak, and

[0027] - condition C is true if an engine damage detection system detects a engine damage.

[0028] According to one embodiment, the fire detection system comprises a fire detection loop and a fire detector.

[0029] According to one embodiment, the hydrogen leak detection system comprises an element selected from a pipe rupture detector, a hydrogen pressure detector, an engine pressure detector, and / or a temperature variation detector.

[0030] According to another aspect, there is provided an aircraft comprising a safety device according to the invention.

[0031] According to another aspect, there is provided a computer program product comprising program code instructions for executing the monitoring method according to the invention, when said instructions are executed by at least one processor.

[0032] According to another aspect there is provided a non-transitory storage medium on which is stored a computer program comprising program code instructions for executing the monitoring method according to the invention, when said instructions are read from said non-transitory storage medium and executed by a processor. Brief description of the drawings

[0033] The characteristics of the invention mentioned above, as well as others, will appear more clearly on reading the following description of at least one exemplary embodiment, said description being made in relation to the attached drawings, among which:

[0034] [Fig-1] schematically illustrates the installation of a monitoring device in an engine;

[0035] [Fig.2] schematically illustrates a computer system;

[0036] [Fig.3] schematically illustrates a monitoring method according to a first mode of realization;

[0037] [Fig.4] schematically illustrates a monitoring method according to a first mode of realization; and

[0038] [Fig.5] schematically illustrates an aircraft comprising an engine and a device for security.

[0039] DETAILED DESCRIPTION OF EMBODIMENTS

[0040] Safety device

[0041] With reference to [Fig.l], according to one aspect, there is provided a safety device 1 for an engine 10 powered by dihydrogen. The safety device 1 is adapted to be installed in and around the engine 10, to monitor the risks of fires in the engine 10.

[0042] The safety device 1 comprises a safety valve 2 movable between an open position in which the engine 10 is supplied with dihydrogen and a closed position in which the engine 10 is no longer supplied with dihydrogen.

[0043] As shown schematically in [Fig.l], according to one embodiment, the safety valve 2 is positioned outside a combustion zone 12 of the engine 10. Indeed, as shown schematically in [Fig.l], the engine 10 is a turbomachine, comprising a combustion zone 12 in which compressors 14 and turbines 16 are located. This architecture of a turbomachine is moreover well known.

[0044] On the other hand, in a particularly clever manner, the safety valve 2 is positioned outside the combustion zone 12 so as to be able to act on (i.e., interrupt) the supply of dihydrogen (i.e. the pipes 18) upstream of the combustion zone 12.

[0045] Advantageously, the combustion zone 12 considered includes all of the zones around the engine 10 into which debris from the engine 10 is likely to be projected in the event of an uncontained engine failure. Thus, since the safety valve 2 is positioned outside the combustion zone 12, the safety valve 2 is not likely to be impacted in the event of an uncontained engine failure.

[0046] According to one embodiment, the safety valve 2 is positioned outside the combustion zone 12, while being as close as possible to the combustion zone 12. This arrangement makes it possible to minimize the quantity of dihydrogen that can still circulate in the pipes 18 after the safety valve 2 has moved to the closed position.

[0047] In addition to the safety valve 2, the safety device 1 also comprises: an engine fire detection system 30, a hydrogen leak detection system 20, an engine damage detection system 40.

[0048] According to one embodiment, the engine fire detection system 30 comprises a fire detection loop and a fire detector. The fire detection loop Fire detection and fire detector are known elements. Typically, the fire detection loop is a pipe filled with a gas. When the heat increases around the pipe (i.e., when there is a fire around the pipe), the gas expands. An expansion sensor associated with the pipe detects the expansion and emits a fire detection signal.

[0049] According to one embodiment, the hydrogen leak detection system 20 comprises a pipe rupture detector, a hydrogen pressure detector, an engine pressure detector, and a temperature variation detector.

[0050] According to one embodiment, the pipe rupture detector operates by measuring a hydrogen pressure in the hydrogen pipe. In the event of a pipe rupture, the pressure varies to tend towards atmospheric pressure. If the detector detects a pressure in the pipe similar to atmospheric pressure, it emits a signal detecting a hydrogen pipe rupture.

[0051] According to one embodiment, the pressure detector in the engine is an ambient pressure detector in the engine. In the event of a variation in the ambient pressure, the detector emits a signal detecting a variation in ambient pressure.

[0052] According to one embodiment, the temperature variation detector may comprise a thermocouple or an optical sensor. According to one embodiment, the temperature variation detector may emit a temperature variation detection signal if a measured temperature is outside a predetermined range. According to another embodiment, the temperature variation detector is adapted to detect an abrupt change in temperature, i.e., a change in temperature beyond a predetermined threshold, over a predetermined duration.

[0053] According to one embodiment, the engine damage detection system 40 is a known system, for example from documents FR3068392 and FR3052747, which will not be described in the present document.

[0054] According to other embodiments, some of the previously mentioned detectors may be absent.

[0055] Computer system

[0056] Furthermore, the security device 1 comprises electronic circuitry adapted to implement a monitoring method 100 which will be described below.

[0057] Thus, according to another aspect, there is provided a computer system 200 comprising electronic circuitry configured to implement a monitoring method 100.

[0058] As shown diagrammatically in [Fig.2], the computer system 200 may comprise, connected by a communication bus 210: a processor 201; a RAM 202; a read-only memory 203, for example of the ROM (“Read Only Memory” in English) or EEPROM (“Electrically-Erasable Programmable Read Only Memory” in English); a storage unit 204, such as a hard disk HDD (“Hard Disk Drive” in English), or a storage media reader, such as an SD (“Secure Digital” in English) card reader; and an input-output interface manager 205.

[0059] The processor 201 is capable of executing instructions loaded into the RAM 202 from the ROM 203, an external memory, a storage medium (such as an SD card), or a communications network. When the computer system 200 is powered on, the processor 201 is capable of reading instructions from the RAM 202 and executing them. These instructions form a computer program allowing the implementation, by the processor 201, of the monitoring method 100 described below.

[0060] All or part of the method 100 can thus be implemented in software form by executing a set of instructions by a programmable machine, for example a DSP (Digital Signal Processor) type processor or a microcontroller, or be implemented in hardware form by a machine or a dedicated component, for example an FPGA (Field Programmable Gate Array) or ASIC (Application-Specified Integrated Circuit) component. In general, the computer system 200 comprises electronic circuitry adapted and configured to implement, in software and / or hardware form, the monitoring method 100 described below in relation to the computer system 200 in question.

[0061] Aircraft

[0062] According to another aspect, as shown diagrammatically in [Fig. 5], there is proposed an aircraft 50 comprising an engine 10 powered by dihydrogen, and further comprising at least one safety device 1 and the computer system 200.

[0063] Monitoring method

[0064] According to another aspect, with reference to Figs. 3 and 4, there is proposed a method 100 for monitoring an engine 10 of the aircraft 50 powered by dihydrogen.

[0065] With reference to Figs. 3 and 4, if a locking authorization is given and if one of the at least three conditions A or B or C is true, then the safety device 1 closes the safety valve 2, with: - condition A is true if a 30-engine fire detection system detects a fire, - condition B is true if a hydrogen leak detection system 20 detects a hydrogen leak, and - condition C is true if an engine damage detection system 40 detects engine damage.

[0066] According to one embodiment, the locking authorization is given based on criteria linked to the availability of another engine 10 of the aircraft 50, for example if a similar problem has not already been detected on the other engine of the aircraft and if the thrust of the other engine is available.

[0067] According to the embodiments shown schematically in Figs. 3 and 4, condition A is true if two conditions A1 and A2 are true, with: - condition A1 is true if a fault in at least one fire detection loop is detected by the fire detection system 30 in question; - condition A2 is true if the fire detection system 30 in question detects a fire.

[0068] Furthermore, according to a particular arrangement, shown diagrammatically in Figs. 3 and 4, the condition A1 is true if two conditions A11 and A12 are true, with: - condition Ail is true if a fault in a first fire detection loop is detected by the fire detection system 30 in question; - condition A12 is true if a fault in a second fire detection loop is detected by the fire detection system 30 in question.

[0069] According to a particular arrangement, the condition A1 is true if both conditions A11 and A12 are true within a predetermined time interval, for example a time interval of 5 seconds.

[0070] According to an embodiment shown schematically in [Fig.3], condition B is true if one of the two conditions B1 or B2 is true, with: - condition B1 is true if a hydrogen pressure lower than a predetermined threshold is detected by a hydrogen leak detection system 20; - condition B2 is true if at least one of the following conditions is met: a hydrogen concentration greater than a predetermined threshold is detected by the hydrogen leak detection system 20 (condition B21); or if a rupture of a hydrogen supply pipe is detected by the hydrogen leak detection system 20 (condition B22); or if a pressure in the engine 10, greater than a predetermined pressure is detected by the hydrogen leak detection system 20 (condition B23); or if a temperature variation greater than a predetermined temperature variation is detected by the hydrogen leak detection system 20 (condition B24).

[0071] According to another embodiment shown diagrammatically in [Fig.4], condition B is true if at least the two conditions B1 and B2 are true.

[0072] According to one embodiment, the open or closed position of the valve 2 is indicated to a user on a display screen. Typically, this display screen may be a control screen in the cockpit of the aircraft 50. According to one embodiment, distinctive visual signals make it possible to inform a user about the state of each detector of the safety device 1. Thus, according to this embodiment, if the valve 2 goes into the closed position, the user is alerted and the various visual signals allow him to know the cause of the valve 2 going into the closed position.

Claims

Claims

1. Method (100) for monitoring an engine (10) of an aircraft (50) powered by dihydrogen, comprising a safety device (1) comprising a safety valve (2) movable between an open position in which the engine (10) is powered by dihydrogen and a closed position in which the engine (10) is no longer powered by dihydrogen, an engine fire detection system, a dihydrogen leak detection system (20) and an engine damage detection system, and comprising electronic circuitry (200) adapted to implement the monitoring method (100), the monitoring method (100) is characterized in that if a locking authorization is given and if one of three conditions A, B and C is true, then the safety device (1) closes the safety valve (2), with: - condition A is true if an engine fire detection system (30) detects a fire,- condition B is true if a hydrogen leak detection system (20) detects a hydrogen leak, and - condition C is true if an engine damage detection system (40) detects engine damage.,

2. The monitoring method (100) according to claim 1, wherein condition B is true if one of the two conditions B1 or B2 is true, with: - condition B1 is true if a hydrogen pressure lower than a predetermined threshold is detected by the hydrogen leak detection system (20); - condition B2 is true if at least one of the following conditions is met: a hydrogen concentration higher than a predetermined threshold is detected by the hydrogen leak detection system (20); or a rupture of a hydrogen supply pipe is detected by the hydrogen leak detection system (20); or a pressure in the engine, higher than a predetermined pressure is detected by the hydrogen leak detection system (20); or a temperature variation higher than a predetermined temperature variation is detected by the hydrogen leak detection system (20).

3. The monitoring method (100) of claim 2, wherein condition B is true if both conditions B1 and B2 are true.

4. A monitoring method (100) according to any preceding claim, wherein condition A is true if two conditions A1 and A2 are true, with: - condition A1 is true if a fault in a fire detection loop is detected by the fire detection system (30); - condition A2 is true if the fire detection system (30) detects a fire.

5. Safety device (1) of an engine (10) powered by dihydrogen characterized in that the safety device (1) comprises: - a safety valve (2) movable between an open position in which the engine (10) is powered by dihydrogen and a closed position in which the engine (10) is no longer powered by dihydrogen; - an engine fire detection system (30); - a dihydrogen leak detection system (20); - an engine damage detection system (40);and - electronic circuitry (200) adapted to implement a monitoring method in which, if a locking authorization is given and if one of the at least three conditions A or B or C is true, then the safety device (1) closes the safety valve (2), with: - condition A is true if an engine fire detection system (30) detects a fire, - condition B is true if a hydrogen leak detection system (20) detects a hydrogen leak, and - condition C is true if an engine damage detection system (40) detects engine damage.;

6. A safety device (1) according to claim 5, wherein the fire detection system (30) comprises a fire detection loop and a fire detector.

7. Safety device (1) according to any one of claims 5 or 6, wherein the hydrogen leak detection system (20) comprises an element selected from a pipe rupture detector, a hydrogen pressure detector, an engine pressure detector, and / or a temperature variation detector.

8. Aircraft (50) comprising a safety device (1) according to any one of claims 5 to 7.

9. Computer program product comprising program code instructions for executing the monitoring method (100) according to one of any of claims 1 to 4, when said instructions are executed by at least one processor (201).

10. A non-transitory storage medium having stored thereon a computer program comprising program code instructions for performing the monitoring method according to any one of claims 1 to 4, when said instructions are read from said non-transitory storage medium and executed by a processor (201).

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