阅读说明：本技术 涡轮发动机的机油系统 (Engine oil system of turbine engine ) 是由 布鲁诺·罗伯特·高利 杰曼·米歇尔·埃曼努埃尔·伯索 伊夫·埃姆普林 于 2020-05-04 设计创作，主要内容包括：一种用于涡轮发动机的机油系统,使得在涡轮发动机内发生火灾的情况下能够继续向涡轮发动机的设备供油,包括：油路(2)；由所述油路(2)供应的至少一个耗油设备部件(3a、3b、3c)；泵送单元,包括至少一个可调速的电动泵(22、4),为所述油路(2)供油；以及电子控制单元(6),配置为引导所述电动泵(22、4),其中所述电子控制单元(6)包括两个单独的引导所述电动泵(22、4)的逻辑,并且其中所述电子控制单元(6)配置为默认情况下根据第一逻辑引导所述电动泵(22、4),并在接收到表示存在火灾或过热的信号时切换到第二逻辑。(An oil system for a turbine engine to enable continued oil supply to equipment of the turbine engine in the event of a fire within the turbine engine, comprising: an oil passage (2); at least one consumer component (3a, 3b, 3c) supplied by the oil circuit (2); a pumping unit comprising at least one speed-adjustable electric pump (22, 4) supplying oil to said oil circuit (2); and an electronic control unit (6) configured to direct the electric pumps (22, 4), wherein the electronic control unit (6) comprises two separate logics to direct the electric pumps (22, 4), and wherein the electronic control unit (6) is configured to direct the electric pumps (22, 4) according to a first logic by default and to switch to a second logic upon receiving a signal indicating the presence of a fire or overheating.)

1. An oil system for a turbine engine, comprising:

an oil passage (2),

at least one consumer component (3a, 3b, 3c) supplied by the oil circuit (2),

a pumping unit comprising at least one speed-adjustable electric pump (22, 4) for supplying said oil circuit (2) with oil, and

an electronic control unit (6) configured to direct the electric pumps (22, 4),

wherein the electronic control unit (6) comprises two separate logics for directing the electric pumps (22, 4),

wherein the electronic control unit (6) is configured to direct the electric pumps (22, 4) according to a first logic by default and to switch to a second logic upon receiving a signal indicating the presence of a fire or overheating.

2. An oil system according to claim 1, wherein the electronic control unit (6) is configured to stop the electric pump (22, 4) upon receiving a leak signal from a leak detector (62).

3. An oil system according to claim 1 or 2, wherein the at least one oil consumer component (3a, 3b, 3c) is an accessory gearbox (30), and

wherein the accessory gearbox (30) includes an accessory gear contained in a housing.

4. An oil system according to claim 3, wherein the accessory gearbox (30) comprises a sprayer (31) configured to spray oil from the oil circuit (2) to at least one wall of a housing of the accessory gearbox (30).

5. An oil system according to any one of claims 1-4, wherein the electric pump (22, 4) is driven by at least one electric motor (4).

6. The oil system of any of claims 1-5, wherein the pumping unit includes a mechanically driven primary pump and an electrically driven secondary pump.

7. The oil system of any of claims 1-6, including at least one fire detector (61) configured to signal the presence of a fire upon detection of a fire in a fire zone of the turbine engine, preferably in the vicinity of the housing of the accessory box (30).

8. An oil system according to any of claims 1-7, including at least one manual switch (63) configured to signal the presence of a fire upon manual activation.

9. An oil system according to any of claims 1-8, wherein in the first control logic the pilot speed of the electric pump (22, 4) is a function of the rotational speed of the body of the turbine engine.

10. An oil system according to any one of claims 1-9, wherein in the second control logic the pilot speed of the electric pump (22, 4) is a predetermined value.

11. An oil system according to any of claims 1-10, wherein in the second control logic the total flow rate of the pumping units is between 100 and 600 litres/hour, preferably between 100 and 300 litres/hour, more preferably between 150 and 200 litres/hour.

12. A turbine engine comprising a component oil system (1) according to any one of claims 1 to 11.

Technical Field

The present disclosure relates to an oil system for a turbine engine that enables continued oil supply to equipment of the turbine engine in the event of a fire within the turbine engine.

Such an oil system can be used in any type of turbine engine, in particular in the aeronautical field, in aircraft turbojet engines.

Background

In turbine engines, the oil system ensures the basic function of supplying oil to the turbine engine components in order to lubricate and/or cool them during all phases of operation, in order to guarantee the correct operation of the turbine engine: in particular, the oil system is responsible for lubricating and cooling the bearings and gears of the turbine engine, as well as cooling the heat exchangers and some housings that are subjected to high temperatures, such as the housings of generators, pumps or gearboxes.

In the current configuration, the pump of the oil system is mechanically driven by an Accessory Gearbox (AGB): the accessory gearbox supports a plurality of turbine engine accessories, which are themselves driven by the body of the turbine engine, most commonly the High Pressure (HP) body, typically through an Intake Gearbox (IGB), a Radial Drive Shaft (RDS), and a drive gearbox (TGB).

Thus, the rotational speed of the pump of the oil system and the oil flow rate are a function of the rotational speed of the turbine engine body driving the accessories.

However, in some cases, it is necessary to stop the engine while continuing to ensure the supply of the oil. For example, in the event of a fire, the fuel inlet is closed and then the speed of the turbine engine is reduced until the spinning speed is reached; however, the oil supply must maintain a sufficient flow rate to lubricate, and in particular cool, the turbine engine components exposed to the additional heat source to ensure their mechanical strength, and in particular to avoid oil leakage which may contribute to a fire hazard.

Therefore, in most current configurations, the pump of the oil system is oversized to ensure a sufficient flow rate even at automatic rotation speeds, thus increasing the mass, space requirements and cost of the oil system, which can affect the fuel consumption of the turbine engine and thus the range of the aircraft turbojet.

Another known option is to add coverings, heat shields or fire shields to the components of the apparatus to limit the effects of heat radiation from a fire. However, this also leads to increased quality, space requirements and costs of the oil system.

There is therefore a real need for an oil system which is at least partly free from the drawbacks inherent in the known arrangements described above.

Disclosure of Invention

The invention relates to an oil system for a turbine engine, comprising:

an oil passage is arranged on the oil pipe,

at least one consumer component supplied by the oil circuit,

a pumping unit comprising at least one speed-adjustable electric pump supplying oil to said oil circuit, an

An electronic control unit configured to direct the electric pump, wherein the electronic control unit includes two separate logics to direct the electric pump,

wherein the electronic control unit is configured to direct the electric pump according to a first logic by default and to switch to a second logic upon receiving a signal indicating the presence of a fire or overheating.

Thus, thanks to such an electric pump, it is possible to overcome the rotational speed of the turbine engine, thereby decoupling the rotational speed of the pump, and therefore the fuel flow rate, from the actual speed of the turbine engine. Thus, the oil system may continue to operate normally even in the event of degraded operation of the turbine engine, such as a shutdown following a fire.

In fact, in particular, the electrical energy required to drive the pump may be provided by the turbine engine and by the aircraft, for example in the case of degraded operation of the turbine engine.

Furthermore, due to the use of such an electric pump, the oil flow rate can be controlled according to the actual needs of the turbine engine, possibly in real time. In particular, this allows to ensure a sufficient oil flow rate, possibly a greater flow rate, in case of fire, in order to effectively cool the components of the plant without having to oversize the pump.

The present configuration also allows for a reduction or elimination of the need for heat shielding due to this improved cooling.

Thus, the quality, space requirements and cost of the current configuration are reduced compared to existing configurations.

In some embodiments, the electronic control unit is configured to stop the electric pump upon receiving a leak signal from the leak detector. This is preferably an oil leakage detector. Thanks to the leak detector, which signals a leak when it measures a pressure drop in the oil circuit above a certain threshold, once a leak is detected, the oil supply can be stopped: thereby reducing or preventing oil leakage flow rates, which reduces the risk of such leaking oil causing fires.

In some embodiments, the first nominal logic allows the electric pump to be directed within a first speed range and the second logic allows the electric pump to be directed within a second speed range in the event of a fire. In this respect it is provided that the first and/or second speed range can be reduced to a single value or a set of discrete values.

In some embodiments, the second speed range is at least on average and preferably strictly greater than the motor's spinning speed, also referred to as the windmill speed.

In some embodiments, the oil circuit comprises one or several of the following elements: pipelines and oil tanks; filtering with a screen; a filter; a fuel/oil exchanger; an air/oil exchanger and a recovery pump.

In some embodiments, the at least one consumer component is an accessory gearbox. In fact, the accessory gearbox is generally located in a fire area, i.e. an area of the turbine engine where a fire is particularly likely to occur and is therefore protected accordingly.

In some embodiments, the accessory gearbox includes an accessory gear contained within the housing.

In some embodiments, the accessory gearbox includes a sprayer configured to spray oil from the oil circuit onto at least one wall, preferably an interior wall, of a housing of the accessory gearbox. Depending on the configuration, these sprinklers can be operated continuously to permanently cool the housing of the accessory gearbox, or only in the event of a fire, in order to cool the housing and delay its melting as far as possible in the event of direct exposure to the fire. In this case, the triggering of the sprinkler can be controlled by the electronic control unit.

In some embodiments, the at least one consumer component is a generator connected to the accessory box. In fact, such generators tend to heat up and therefore require cooling.

In some embodiments, the at least one oil consumer component is a housing containing at least one bearing. In fact, such bearings require a lubricating function and a cooling function.

In some embodiments, the electric pump is driven by at least one electric motor. The electric motor may in particular be of the direct current type or of the asynchronous type.

In some embodiments, the electric pump is driven by two redundant electric motors. In this way, continuity of the oil supply is ensured even in the event of failure of one of the electric motors, for example if the latter is located at the origin of a detected fire.

In some embodiments, the pumping unit includes a mechanically driven main pump and an electrically driven auxiliary pump, for example, coupled to the accessory gearbox. In this way, the main pump can ensure the oil supply during normal operation, and the auxiliary pump takes over or at least assists the main pump during degraded operation: in this case, the main pump, although mechanically driven, can be kept at a moderate size.

In some embodiments, the oil system includes at least one fire detector configured to signal the presence of a fire upon detecting the presence of a fire in a fire zone of the turbine engine, preferably in the vicinity of the housing of the accessory box. For example, the fire detector may be located between the housing of the accessory box and the boundary of the fire zone in which the accessory box is located. In particular, when the accessory case is located radially outside the secondary flow path, this fire zone may be defined by the fan housing and the outer fan duct wall on the one hand and by the nacelle housing on the other hand; when the accessory case is located radially between the primary and secondary flow paths, the fire zone may be defined between the motor housing on the one hand and the inner fan duct wall on the other hand. For example, when the detector measures a temperature above a certain threshold, it may signal the presence of a fire.

In some embodiments, the fire detector is of the pneumatic type, for example triggered by the expansion of a gas contained in the enclosure.

In some embodiments, the fire detector is of the thermocouple type.

In some embodiments, the fire detector is of the thermistor type.

In some embodiments, at least one fire detector is mounted on the housing of the accessory gearbox. Thus, when a fire threatens the integrity of the accessory gearbox, the second control logic can be switched.

In some embodiments, the oil system includes at least one manual switch configured to signal the presence of a fire upon manual activation. This allows the pilot of the aircraft to force a switch to the second control logic, for example when other information indicates to him that there is a fire in the turbine engine.

In some embodiments, the first control logic is based on a normal operating speed of the turbine engine. Thus, the first control logic substantially reproduces the behavior of the pump driven by the accessory gearbox.

In some embodiments, in the first control logic, the pilot speed of the electric pump is a function of the rotational speed of the turbine engine body, preferably the high pressure body of the turbine engine. For example, the pilot speed of the electric pump may be proportional to the rotational speed of the turbine engine body. The pilot speed may also be adjusted so that the total flow rate of the pumping units is proportional to the rotational speed of the turbine engine body. In this way, the supply flow rate is significantly increased according to the oil demand of the turbine engine.

In some embodiments, the second control logic is based on a spin speed of the turbine engine. Thus allowing to take into account the fact that the turbine engine rotates at a reduced speed; however, this does not mean that the pilot speed in the second control logic corresponds to the turbine engine autorotation speed; conversely, the pilot speed is generally higher than the spin speed. Thus, in the second control logic, the pilot speed is not directly proportional to the rotational speed of any body of the turbine engine.

In some embodiments, in the second control logic, the pilot speed of the electric pump is a predetermined value, possibly taking into account a model of the turbine engine. The pilot speed may also be adjusted such that the total flow rate of the pumping unit assumes a predetermined value, possibly taking into account the model of the turbine engine. In fact, in the second control logic, the need for oil is mainly related to the cooling need needed for fire fighting, and therefore is not dependent or practically independent of the speed of the turbine engine. In particular, the predetermined value may be selected to ensure the following flow rate.

In some embodiments, in the second control logic, the total flow rate of the pumping units is between 100 and 600 liters/hour, preferably between 100 and 300 liters/hour, more preferably between 150 and 200 liters/hour.

The present disclosure also relates to a turbine engine comprising an oil system according to any of the preceding embodiments.

The above features and advantages, as well as others, will become apparent from a reading of the following detailed description of exemplary embodiments of the proposed oil system. The detailed description refers to the accompanying drawings.

Drawings

The drawings are schematic and are primarily intended to illustrate the principles of the present disclosure.

In the drawings, like elements (or portions of elements) are identified by like reference numerals from one figure to another.

Fig.1 is a diagram of a first engine oil system according to the present disclosure.

Fig.2 shows a control flow chart of the oil system.

FIG.3 is a diagram of a second oil system according to the present disclosure.

Detailed Description

To make the present disclosure more specific, examples of oil systems are described in detail below with reference to the accompanying drawings. It should be noted that the present invention is not limited to this example.

Fig.1 schematically illustrates a first example of an oil system 1 according to the present disclosure.

The oil system 1 includes an oil passage 2, and the oil passage 2 supplies oil to a plurality of equipment components 3a, 3b, 3 c. The oil circuit 2 comprises, from upstream to downstream, a tank 20, a strainer 21, a feed pump 22, a filter 23, a fuel/oil exchanger 24, an air/oil exchanger 25, pieces of equipment 3, each of which is provided on a separate supply branch 2a, 2b, 2c, bypassing each other, and a strainer 26 and a recovery pump 27, which are located downstream of each piece of equipment 3, so that oil can be returned from each supply branch 2a, 2b, 2c to the tank 20.

In the present example, the equipment component 3a, 3b, 3c comprises a gearbox, preferably an accessory gearbox 30 of a turbine engine. More specifically, therefore, the oil circuit 2 comprises a plurality of sprayers 31 arranged inside the accessory gearbox 30 for spraying the oil on its gears and on at least some of the internal walls of its housing. The oil thus ejected is then recovered at the lowest point of the accessory gearbox 30. The equipment parts 3a, 3b, 3c may also comprise housings or bearing housings for other gearboxes, other accessories. Some of these equipment components 3a, 3b, 3c may be driven by the accessory gearbox 30 using a mechanical transmission 32. It goes without saying that the oil circuit 2 may supply any number of equipment parts 3a, 3b, 3c, not just the three shown in fig. 1.

The oil system 1 further comprises an electric motor 4, the mechanical output of which is coupled to the supply pump 22 to drive it. As such, it is powered by a power supply 5 provided on the turbine engine itself and/or on the aircraft: it may be, for example, a generator, a battery, or a combination of both devices. Preferably, the power supply 5 will be ensured by the generator of the turbine engine, which is driven by the rotation of the turbine engine in normal operation, and by the battery provided on board the aircraft in degraded operation, for example in case of fire. In the present example, the electric motor 4 is of asynchronous type.

The oil system 1 further comprises an electronic control unit 6 powered by the power source 5 and configured to control the electric motor 4. More specifically, in most cases, the electronic control unit 6 actually controls an inverter that varies the current supplied to the electric motor 4, so as to vary the speed of rotation of the latter and therefore of the pilot supply pump 22. However, in other examples, it may be any other electric motor guidance device.

The oil system 1 further includes at least one fire detector 61 mounted on the housing of the accessory gearbox 30, and a leak detector 62 disposed within the accessory gearbox 30. In the present example, the fire detector 61 is a pneumatic detector, wherein the gas expands when the temperature exceeds a predetermined threshold until a switch is activated; the leak detector 62 itself detects an abnormal pressure drop between two points of the oil passage 2. The oil system 1 further comprises at least one switch 63 provided in the aircraft cockpit: it allows the pilot to manually report the presence of a fire. The electronic control unit 6 receives as input the signals of these detectors 61, 62 and the switch 63.

Of course, the electronic control unit 6 may receive signals from more detectors and/or switches. More generally, the electronic control unit 6 can be integrated in the FADEC (full authority digital engine control) of the turbine engine.

At least two control logics of the electric motor 4 are stored in a memory of the electronic control unit 6: a first control logic, referred to as nominal logic; and a second control logic, referred to as fire logic.

The nominal logic is programmed to reproduce as much as possible the behaviour of the mechanically driven pump coupled to the HP shaft of the turbine engine. Thus, in the present example, the nominal logic is used to control the electric motor 4 so that its rotational speed is proportional to the rotational speed of the HP body of the turbine engine, commonly referred to as speed N2. Suitable sensors allow the transmission of information relating to this speed N2 to the electronic control unit 6.

The fire logic is programmed to ensure a sufficient oil flow rate in the event of a fire, so that the cooling of the installation components 3a, 3b, 3c which radiate heat towards the fire can be ensured in order to retain them at least for the legally minimum time. It takes into account in particular the fact that in the event of a fire, the fuel supply to the turbine engine is interrupted, so that its speed is greatly reduced, in fact corresponding to the autorotation speed of the turbine engine. Thus, in the present example, the fire logic is used to control the electric motor 4 so that its rotational speed or the flow rate of the feed pump 22 equals a predetermined value. In this example, the fire logic controls the electric motor 4 to ensure a supply flow rate of 150 litres/hour.

A control routine of the electronic control unit 6 stored in the memory of the electronic control unit 6 will now be presented with reference to fig. 2.

At the start of the routine, the nominal logic is selected by default (step 71), and the routine then proceeds to step 72.

During this step 72, the electronic control unit 6 checks whether the detector 61 detects a fire: if not, the routine proceeds to step 73; conversely, if a fire is detected, the routine proceeds to step 74.

If no fire is detected, the electronic control unit 6 checks during step 73 whether the pilot has activated the switch 63: if not, the routine returns to step 72; conversely, if the pilot has activated the switch 63, thereby manually reporting the presence of a fire, the routine proceeds to step 74.

Thus, as long as the detector 61 neither detects the presence of a fire nor reports the presence of a fire by the pilot using the switch 63, the routine loops and therefore keeps the nominal logic active.

On the other hand, if a fire is detected or reported, the routine goes to step 74. During this step 74, the electronic control unit 6 checks whether the oil leakage is detected by the probe 62; if not, the routine proceeds to step 75; conversely, if a leak is detected, the routine proceeds to step 76.

In case no leakage is detected, the electronic control unit 6 switches to fire logic during step 75 and returns to step 72.

Thus, as long as there is a fire and no leak is detected, the routine will loop and keep the fire logic active.

On the other hand, if a leak is detected, the routine reaches a step 75, and the electronic control unit 6 then triggers the stop of the electric motor 4 and therefore of the feed pump 22, to avoid that the leaked oil contributes to the fire. The routine then ends.

In this example, the detector 61 is a detector intended to detect the presence of a fire. However, the detector or an additional detector may also detect the presence of overheating, even before the fire has started. For example, the system may include one or more probes capable of detecting abnormal temperature increases or bursts of some components of the system, such as pipes.

FIG.3 schematically illustrates a second example of an oil system 101 according to the present disclosure.

The oil system 101 is very similar to that of the first example, except that its pumping unit includes a mechanical main pump 128 driven by an accessory gearbox 130 using a mechanical transmission 129, and an auxiliary pump 122, similar to the supply pump 22 of the first example, driven by the output of the electric motor 104.

As a first example, at least two control logics of the electric motor 104 are stored in a memory of the electronic control unit 106: a first control logic, referred to as nominal logic; and a second control logic, referred to as fire logic.

Nominal logic corresponding to normal operation of the turbine engine dictates that the electric motor 104 is controlled at low or zero speed: in fact, the main pump 128 is driven by the accessory gearbox 130, the rotational speed of which is already proportional to the speed of the high-pressure body of the turbine engine, so that a single main pump ensures a sufficient oil flow rate for the proper operation of the turbine engine.

Given the substantial reduction in turbine engine speed, the main pump 128 speed is therefore also substantially reduced, and therefore the fire logic is programmed to ensure that there is a sufficient oil flow rate in the fire. Thus, as in the first example, the fire logic provides for controlling the electric motor 104 so that its rotation speed or the flow rate of the pumping unit is equal to a predetermined value, for example chosen to ensure a supply flow rate of 150 litres/hour.

The control routine of the electronic control unit 106 stored in the memory of the electronic control unit 106 is similar to that of the first example shown in fig. 2.

Although the present invention has been described with reference to specific exemplary embodiments, it will be apparent that modifications and variations can be made to these examples without departing from the general scope of the invention as defined in the claims. In particular, individual features of different illustrated/referenced embodiments may be combined in additional embodiments. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

All features described with reference to a method may be transposed individually or in combination to an apparatus, whereas all features described with reference to an apparatus may be transposed individually or in combination to a method.