阅读说明：本技术 一种飞机燃油增压系统及控制方法 (Aircraft fuel oil pressurization system and control method ) 是由 李长亮 杨巍 谷可帅 张文博 刘中宝 王磊 陈登 于 2021-08-13 设计创作，主要内容包括：一种飞机燃油增压系统及控制方法,飞机燃油增压系统包括燃油箱、涡轮增压器、单向阀和减压阀；其中,燃油箱设有通气入口；涡轮增压器的气体出口与通气入口通过管路连通,用于向燃油箱内提供增压气体；单向阀设于管路上,用于使增压气体从气体出口流向通气入口；减压阀设于单向阀和通气入口之间。本发明涉及的飞机燃油增压系统,燃油箱与涡轮增压器构成封闭的系统,利用涡轮增压器的气体对燃油箱内进行增压,能够提高绝对压力,增加燃油饱和蒸汽压和燃油箱压力差值,有利于发动机稳定运行。(An aircraft fuel pressurization system and a control method thereof, wherein the aircraft fuel pressurization system comprises a fuel tank, a turbocharger, a one-way valve and a pressure reducing valve; wherein, the fuel tank is provided with a ventilation inlet; the gas outlet of the turbocharger is communicated with the ventilation inlet through a pipeline and used for providing pressurized gas into the fuel tank; the one-way valve is arranged on the pipeline and used for enabling the pressurized gas to flow from the gas outlet to the ventilation inlet; the pressure relief valve is disposed between the check valve and the vent inlet. According to the aircraft fuel oil pressurization system, the fuel oil tank and the turbocharger form a closed system, gas of the turbocharger is utilized to pressurize the fuel oil tank, absolute pressure can be improved, fuel oil saturation vapor pressure and a fuel oil tank pressure difference value are increased, and stable operation of an engine is facilitated.)

1. An aircraft fuel pressurization system is characterized by comprising a fuel tank (1), a turbocharger (3), a one-way valve (5) and a pressure reducing valve (6); wherein the content of the first and second substances,

the fuel tank (1) is provided with a ventilation inlet;

the gas outlet of the turbocharger (3) is communicated with the ventilation inlet through a pipeline and is used for providing pressurized gas into the fuel tank (1);

the one-way valve (5) is arranged on the pipeline and is used for enabling the pressurized gas to flow from the gas outlet to the ventilation inlet;

the pressure reducing valve (6) is arranged between the one-way valve (5) and the ventilation inlet.

2. An aircraft fuel pressurization system according to claim 1, further comprising a processor, a pressure sensor (10) and a filter (4), said pressure sensor (10) being adapted to monitor the pressure within said fuel tank (1), said pressure sensor (10) being communicatively connected to said processor;

the filter (4) is arranged between the gas outlet and the one-way valve (5).

3. An aircraft fuel pressurization system according to claim 2, characterized by further comprising an anti-vacuum valve (7), said anti-vacuum valve (7) being provided on said line and located between said pressure reducing valve (6) and said vent inlet or connected to said fuel tank (1), and communicating with the outside;

and when the pressure of the pipeline is lower than the first preset value, the vacuum-proof valve (7) is automatically opened to introduce external air.

4. An aircraft fuel pressurization system according to claim 3, characterized in that it further comprises a safety valve (8), said safety valve (8) being provided on said line and being located between said pressure reducing valve (6) and said vent inlet or being connected to said fuel tank (1) and communicating with the outside;

when the pressure of the pipeline is higher than the second preset value, the safety valve (8) is automatically opened to discharge air to the outside.

5. An aircraft fuel pressurization system according to claim 2, further comprising a manual pressure relief valve (9), said manual pressure relief valve (9) being provided on said conduit and located between said pressure relief valve (6) and said vent inlet or connected to said fuel tank (1), and communicating with the outside for relieving pressure within said fuel tank (1).

6. An aircraft fuel pressurization system according to claim 4, further comprising a thermostatic heating system for keeping at least one of said check valve (5), said pressure reducing valve (6), said anti-vacuum valve (7) and said safety valve (8) warm.

7. An aircraft fuel pressurization system according to claim 2, further comprising a temperature sensor (2) and a fuel pump (11), said fuel pump (11) being in communication with an outlet of said fuel tank (1) for delivering fuel in said fuel tank (1) to an engine through an outlet line, said temperature sensor (2) being for monitoring the temperature of the fuel in said outlet line.

8. A method of controlling an aircraft fuel booster system according to any one of claims 1 to 7, the method comprising:

step 1, obtaining the environmental pressure P1 of the current flight position; acquiring the current fuel temperature T, acquiring a saturated vapor pressure P2 and an allowable pressure value P0 according to the fuel temperature T and the fuel characteristics, and calculating a pressure difference delta P which is P1-P2;

step 2, when delta P is smaller than P0, adjusting the accelerator opening of the engineAt least one parameter of the rotating speed n and the altitude H is used for adjusting the size of the turbine pressure F output by the turbocharger (3) so that the charging pressure P after the turbine pressure F is decompressed by the decompression valve (6) is not less than P0.

9. The method of controlling an aircraft fuel pressurization system according to claim 8, further comprising:

determining the rotation speed of the airplane in the cruising state, and respectively calculating the minimum oil threshold value under different altitudes H aiming at each rotation speed

Maintaining throttle opening of the engine while the aircraft is in cruise conditionIs always higher than the minimum oil threshold valueSo that said boost pressure P in cruising conditions is greater than a third preset value.

10. The method of controlling an aircraft fuel pressurization system according to claim 8, further comprising:

determining the rotating speed of the airplane in the glide state, and respectively calculating the minimum oil threshold value under different altitudes H aiming at each rotating speed

Maintaining the throttle opening of the engine when the aircraft is in a glide stateIs always higher than the minimum oil threshold valueSo that the boost pressure P in the downslide state is greater than a fourth preset value.

Technical Field

The invention belongs to the technical field of unmanned aerial vehicles, and particularly relates to an aircraft fuel oil pressurization system and a control method.

Background

In small and medium-sized drones, piston engines are generally used as power. The piston engine has mature technology, high reliability and good fuel economy. In fuel systems, the atmosphere is typically vented at the top of the fuel tank to prevent the fuel tank from developing excessive high or low pressures. However, in this case, when the ambient pressure is close to the saturated vapor pressure of the fuel, the oil pump may generate a strong cavitation phenomenon, which may cause a fuel supply failure and prevent the engine from operating stably. Therefore, there is a need for an aircraft fuel pressurization system that increases the absolute pressure, increases the fuel saturation vapor pressure, and increases the fuel tank pressure differential, and allows stable engine operation.

Disclosure of Invention

The invention aims to provide an aircraft fuel oil pressurization system and a control method, which can improve absolute pressure, increase fuel oil saturation vapor pressure and fuel tank pressure difference and enable an engine to stably operate.

In order to achieve the above object, the present invention provides an aircraft fuel pressurization system, comprising a fuel tank, a turbocharger, a check valve and a pressure reducing valve; wherein the content of the first and second substances,

the fuel tank is provided with a ventilation inlet;

the gas outlet of the turbocharger is communicated with the ventilation inlet through a pipeline and is used for providing pressurized gas into the fuel tank;

the one-way valve is arranged on the pipeline and is used for enabling the pressurized gas to flow from the gas outlet to the ventilation inlet;

the pressure relief valve is disposed between the one-way valve and the vent inlet.

Preferably, the fuel tank system further comprises a processor, a pressure sensor and a filter, wherein the pressure sensor is used for monitoring the pressure in the fuel tank, and the pressure sensor is connected with the processor in a communication mode;

the filter is arranged between the gas outlet and the one-way valve;

preferably, the fuel tank further comprises an anti-vacuum valve which is arranged on the pipeline, positioned between the pressure reducing valve and the ventilation inlet or connected to the fuel tank, and communicated with the outside;

and when the pressure of the pipeline is lower than the first preset value, the vacuum-proof valve is automatically opened to introduce external air.

Preferably, the fuel tank further comprises a safety valve which is arranged on the pipeline, positioned between the pressure reducing valve and the ventilation inlet or connected to the fuel tank and communicated with the outside;

when the pressure of the pipeline is higher than a second preset value, the safety valve is automatically opened to discharge air to the outside.

Preferably, the fuel tank further comprises a manual pressure relief valve, wherein the manual pressure relief valve is arranged on the pipeline and located between the pressure relief valve and the ventilation inlet or connected to the fuel tank, communicated with the outside and used for relieving the pressure in the fuel tank.

Preferably, the heating device further comprises a constant-temperature heating system, and the constant-temperature heating system is used for heating and insulating at least one of the one-way valve, the pressure reducing valve, the vacuum-proof valve and the safety valve.

Preferably, the fuel pump is communicated with an oil outlet of the fuel tank and used for conveying the fuel in the fuel tank to an engine through an oil outlet pipeline, and the temperature sensor is used for monitoring the temperature of the fuel in the oil outlet pipeline.

The invention also provides a control method of the aircraft fuel pressurization system, which comprises the following steps:

step 1, obtaining the environmental pressure P1 of the current flight position; acquiring the current fuel temperature T, acquiring a saturated vapor pressure P2 and an allowable pressure value P0 according to the fuel temperature T and the fuel characteristics, and calculating a pressure difference delta P which is P1-P2;

step 2, when delta P is smaller than P0, adjusting the accelerator opening of the engineAt least one parameter of the rotating speed n and the altitude H is used for adjusting the size of the turbine pressure F output by the turbocharger, so that the charging pressure P after the turbine pressure F is decompressed by the decompression valve is not less than P0.

Preferably, the method further comprises:

determining the rotation speed of the airplane in the cruising state, and respectively calculating the minimum oil threshold value under different altitudes H aiming at each rotation speed

Maintaining throttle opening of the engine while the aircraft is in cruise conditionIs always higher than the minimum oil threshold valueSo that said boost pressure P in cruising conditions is greater than a third preset value.

Preferably, the method further comprises:

determining the rotating speed of the airplane in the glide state, and respectively calculating the minimum oil threshold value under different altitudes H aiming at each rotating speed

Maintaining the throttle opening of the engine when the aircraft is in a glide stateIs always higher than the minimum oil threshold valueSo that the boost pressure P in the downslide state is greater than a fourth preset value.

The invention relates to an aircraft fuel oil pressurization system, which has the beneficial effects that: the fuel tank and the turbocharger form a closed system, and the gas of the turbocharger is used for pressurizing the fuel tank, so that the absolute pressure can be improved, the saturated vapor pressure of the fuel and the pressure difference value of the fuel tank are increased, and the stable operation of an engine is facilitated; through the control method of the fuel oil supercharging system, the condition of stable operation of the supercharging system can be obtained, and when the condition is not met, relevant parameters can be adjusted to enable the supercharging system to operate stably.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent by describing in more detail exemplary embodiments thereof with reference to the attached drawings, in which like reference numerals generally represent like parts throughout.

FIG. 1 illustrates a schematic diagram of an aircraft fuel pressurization system, according to one embodiment of the present invention;

FIG. 2 illustrates a graphical plot of boost pressure, altitude, and throttle opening for an aircraft fuel booster system, according to an embodiment of the present invention.

Description of reference numerals:

1. the system comprises a fuel tank, a temperature sensor, a turbocharger 3, a filter 4, a check valve 5, a pressure reducing valve 6, an anti-vacuum valve 7, a safety valve 8, a manual pressure relief valve 9, a pressure sensor 10 and a fuel pump 11.

Detailed Description

Preferred embodiments of the present invention will be described in more detail below. While the following describes preferred embodiments of the present invention, it should be understood that the present invention may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In order to solve the problems in the prior art, the invention provides an aircraft fuel pressurization system, which comprises a fuel tank 1, a turbocharger 3, a one-way valve 5 and a pressure reducing valve 6, as shown in figure 1; wherein the content of the first and second substances,

the fuel tank 1 is provided with a ventilation inlet;

the gas outlet of the turbocharger 3 is communicated with the ventilation inlet through a pipeline and is used for providing pressurized gas into the fuel tank 1;

the check valve 5 is arranged on the pipeline and used for enabling the pressurized gas to flow from the gas outlet to the ventilation inlet;

a pressure relief valve 6 is provided between the one-way valve 5 and the vent inlet. The turbocharger 3 belongs to a component part of an engine of an aircraft, and is connected to an engine body for outputting pressurized gas. According to the aircraft fuel oil pressurization system, the fuel oil tank 1 and the turbocharger 3 form a closed system, and the gas of the turbocharger 3 is utilized to pressurize the fuel oil tank 1, so that the absolute pressure, the saturated vapor pressure of pressurized fuel oil and the pressure difference of the fuel oil tank can be improved, and the stable operation of an engine is facilitated.

Piston engines used in aviation are generally provided with a turbocharger 3, the boosting system provided by the invention is used for conducting air bleeding behind the turbocharger 3 to boost the fuel tank 1, and the fuel tank 1 is connected with a fuel boosting system to form a set of closed fuel tank environment.

The gas led from the turbocharger 3 enters the one-way valve 5, and the one-way valve 5 only allows the gas to flow from the turbocharger 3 to the fuel tank 1 so as to prevent the gas from flowing backwards in an accidental situation;

after the gas flows out from the check valve 5, the gas enters the pressure reducing valve 6, and because the pressure of the gas after the turbocharger 3 is supercharged is changed greatly under different working conditions, and under a large working condition, the pressure of the gas after the turbocharger is greatly larger than the pressure required by fuel oil pressurization, the pressure reducing valve 6 is required to reduce the pressure of the gas after the turbocharger 3 is supercharged, so that the gas is kept in a large supercharging range of the turbocharger, and a supercharging system can provide a constant supercharging pressure for the fuel oil.

The fuel pressurization system of the present invention further comprises a processor and a pressure sensor 10 and a filter 4, wherein the pressure sensor 10 is used for monitoring the pressure in the fuel tank 1, and the pressure sensor 10 is connected with the processor in a communication way. The pressure sensor 10 can monitor the supercharging pressure in real time, and is beneficial to controlling the whole supercharging system;

the filter 4 is arranged between the gas outlet and the one-way valve 5 and is used for filtering the gas discharged by the turbocharger 3 to avoid impurities from damaging each valve.

The gas led from the turbocharger 3 first passes through a filter 4, the filter 4 is used for filtering the gas output by the turbocharger 3 to protect each valve in the supercharging system, and the filter 4 can be a common gas filter and can filter impurities such as dust in the gas; after the gas comes out of the filter 4, it goes through the check valve 5 and enters the pipeline.

The fuel oil pressurization system also comprises an anti-vacuum valve 7, wherein the anti-vacuum valve 7 is arranged on the pipeline, is positioned between the pressure reducing valve 6 and the ventilation inlet or is connected to the fuel oil tank 1, and is communicated with the outside;

when the pressure of the pipeline is lower than the first preset value, the vacuum-proof valve 7 is automatically opened to introduce external air, so that the damage caused by overhigh negative pressure of the fuel tank 1 is prevented.

The anti-vacuum valve 7 is used for preventing the fuel tank 1 from generating large negative pressure relative to the air environment at that time, the first preset value is an opening threshold value of the anti-vacuum valve 7 and a value determined for a valve design state, the value is a certain negative pressure value and can be-1 to-10 kPa, the first preset value can be a factory set value and can also be adjusted to a certain preset value, when the pressure of a pipeline is smaller than the first preset value, the anti-vacuum valve 7 is automatically opened, the anti-vacuum valve 7 is an existing product, and the structure and the principle are not repeated.

The general conditions for the generation of negative pressure in the fuel tank 1 include: the aircraft descends rapidly, the pressure in the fuel tank 1 rises gradually, the external pressure rises rapidly, and the fuel tank 1 generates negative pressure due to the fact that the external pressure rises too fast; the system is damaged, pressurization cannot be provided for fuel oil, and the fuel tank 1 generates negative pressure when the aircraft consumes normal fuel oil or descends;

when the pressure in the fuel tank 1 is lower than the external pressure by a certain value under a certain condition and the condition is continuously aggravated, and the pressure sensor 10 monitors that the pressure of a pipeline is reduced and is close to or even lower than a first preset value, the anti-vacuum valve 7 is automatically opened, so that the external gas is introduced into the fuel tank 1 to supplement the pressure in the fuel tank 1, and the pressure in the fuel tank 1 is kept not lower than the first preset value.

The fuel oil pressurization system also comprises a safety valve 8, wherein the safety valve 8 is arranged on the pipeline, is positioned between the pressure reducing valve 6 and the ventilation inlet or is connected to the fuel oil tank 1, and is communicated with the outside;

when the pressure of the pipeline is higher than the second preset value, the safety valve 8 is automatically opened to discharge air to the outside, so that damage caused by overhigh pressure of the fuel tank 1 is prevented.

The safety valve 8 is used for preventing the fuel tank 1 from generating larger positive pressure relative to the air environment at that time, the second preset value is an opening threshold value of the safety valve 8, the opening threshold value is a value determined in valve design, a certain positive pressure value can be 10-30kPa, when the pressure of a pipeline is higher than the second preset value, the safety valve 8 is automatically opened, the safety valve 8 is an existing product, and the structure and the principle are not repeated;

the general situation in which a high pressure in the fuel tank 1, i.e. a pressure above the normal pressurization value, occurs includes: in the climbing process of the airplane, the pressure in the fuel tank 1 is almost unchanged, and the external pressure is rapidly reduced, so that the fuel tank 1 generates high pressure;

when the pressure in the fuel tank 1 monitored by the pressure sensor 10 rises and gradually approaches or even exceeds the second preset value under certain conditions, the safety valve 8 is automatically opened to output gas to the outside to reduce the pressure in the fuel tank 1, thereby keeping the positive pressure in the fuel tank 1 from being higher than the second preset value.

It should be noted that, under the normal steady-state supercharging condition, the supercharging pressure output by the fuel supercharging system is smaller than the second preset value, and at this time, the safety valve 8 is in a closed state.

The fuel oil pressurization system further comprises a manual pressure relief valve 9, wherein the manual pressure relief valve 9 is arranged on the pipeline, is positioned between the pressure relief valve 6 and the ventilation inlet or is connected to the fuel oil tank 1, is communicated with the outside and is used for relieving the pressure in the fuel oil tank 1.

The manual pressure relief valve 9 is used for manually relieving the pressure in the fuel tank 1, and the manual pressure relief valve 9 can also be automatically opened under the control of a processor, such as an electromagnetic valve. When an airplane lands, in order to keep the fuel tank 1 placed without pressure, gas in the fuel tank 1 needs to be discharged firstly; or when in refueling, the cover can be opened to refuel after the gas in the fuel tank 1 is discharged. The use requirement can be met through the manual pressure relief valve 9.

The fuel oil pressurization system also comprises a constant temperature heating system, and the constant temperature heating system is used for heating and insulating at least one of the check valve 5, the pressure reducing valve 6, the vacuum-proof valve 7 and the safety valve 8. The constant temperature heating system can include the heating plate, the heating plate is used for heating each valve, also can be through temperature-detecting device like sensor monitoring heating temperature, constant temperature heating system's purpose keeps the valve not to freeze when the extremely low temperature condition appears in the air sometimes, avoid because the aircraft flight is at extremely low temperature, the great environment of humidity, and produce and freeze, the unable condition of opening of valve, guarantee the pressurization system safe operation, when using, can carry out the apolegamy according to actual conditions, dispose the heat retaining valve of needs heating among the fuel pressurization system, and not necessarily all valves set up constant temperature heating system, also can all valves all not heat.

The fuel oil pressurization system further comprises a temperature sensor 2 and a fuel oil pump 11, wherein the fuel oil pump 11 is communicated with an oil outlet of the fuel oil tank 1 and used for conveying fuel oil in the fuel oil tank 1 to an engine through an oil outlet pipeline, and the temperature sensor 2 is used for monitoring the temperature of the fuel oil in the oil outlet pipeline.

The fuel oil pressurization system can be arranged on the basis of an original fuel oil system, a fuel oil tank 1 enters an engine branch through a fuel oil pump 11, a temperature sensor 2 is arranged during fuel oil output, the fuel oil temperature is monitored in real time, compared with the prior art that atmosphere is introduced into the fuel oil tank 1, the fuel oil pressurization system is additionally arranged, the absolute pressure can be improved, the fuel oil saturation vapor pressure and the fuel oil tank pressure difference value are opened, and stable operation of an engine is facilitated.

The invention also provides a control method of the aircraft fuel oil pressurization system, which comprises the following steps:

step 1, obtaining the environmental pressure P1 of the current flight position; acquiring a current fuel temperature T, acquiring a saturated vapor pressure P2 and an allowable pressure value P0 according to the fuel temperature T and the fuel characteristics, calculating a pressure difference delta P which is P1-P2, and acquiring the allowable pressure value P0 according to the characteristics of the pump;

step 2, when the delta P is smaller than P0, adjusting the accelerator opening of the engineAt least one parameter of the rotating speed n and the altitude H is used for adjusting the turbine pressure F output by the turbocharger 3, so that the boost pressure P obtained by reducing the turbine pressure F through the reducing valve 6 is not less than P0, and the fuel oil pressurization system can normally operate, wherein the boost pressure P can be obtained through an aircraft instrument.

The allowable pressure value P0 is preset according to the requirement, the flying environment pressure P1 can be obtained by measuring the system of the airplane, the fuel temperature T can be obtained by measuring the temperature sensor 2, the fuel property and the process of obtaining the saturated vapor pressure according to the fuel property and the temperature of the combustible oil are the prior art, and the specific calculation process is not repeated;

when the delta P is not less than P0, the fuel oil supercharging system can normally operate, wherein the supercharging pressure P is always kept higher than the minimum pressure preset value during the flight.

The exhaust port of the engine is communicated with the gas inlet of the turbocharger 3, the exhaust amount of the engine can determine the gas pressure boosted by the turbocharger 3 and the accelerator opening of the engineThe rotating speed n and the altitude H are relevant parameters of the engine, the gas pressure after the turbocharger 3 is supercharged, namely the turbine pressure F, can be determined through the parameters, and the opening degree of the accelerator is properly adjusted according to the requirement of the flight working conditionOr the rotation speed n, to regulate the displacement of the engine and thus the pressure of the gas pressurized by the turbocharger 3, the regulation process also belonging to the conventional operation means of the person skilled in the art;

the boost pressure P is a pressure reduced by the pressure reducing valve 6, the calculation of the pressure reduction amount of the pressure reducing valve 6 is the prior art, and details are not repeated here, and the boost pressure P reduced by the pressure reducing valve and the turbine pressure F are in a one-to-one correspondence relationship, so that the throttle opening of the engine is adjustedThe rotating speed n and the altitude H can adjust the magnitude of the supercharging pressure P.

Boost pressure P, altitude H, and throttle opening of an aircraft fuel booster system as shown in FIG. 2The abscissa is altitude, the ordinate is boost pressure, s1, s2, s3 in the graph are relationship curves of boost pressure P and altitude H under different throttle openings, respectively, the relationship curves are related to the characteristics of the engine, and are prior art in the field and not described in detailThe relationship between the rotating speed n and the altitude H can ensure that the supercharging system works normally. If the altitude normally reaches a certain altitude and has a corresponding minimum pressure preset value, the accelerator opening degree can be adjustedThe boost pressure P is not less than P0 and is always higher than the lowest pressure preset value in the flight process, so that the fuel oil boosting system can normally operate, and the engine can stably operate.

The method is a high-speed dynamic adjusting method, and because the maximum supercharging airflow is sometimes considered to be limited in the design of a supercharging system so as to ensure that the air entraining quantity is not too large and the normal work of an engine is not influenced when the system fails, the method is more suitable for pre-estimating adjustment and real-time micro correction which cannot complete high-speed dynamic adjustment. By the method, the condition of stable operation of the pressurization system can be obtained, when the condition is not met, the relevant parameters are adjusted to enable the pressurization system to operate stably, the pressurization pressure can be obtained according to the parameters of the engine when the airplane flies, and the relevant parameters are adjusted according to the working conditions to enable the pressurization system to operate stably.

The method further comprises the following steps:

determining the rotation speed of the aircraft in a cruising state, and respectively calculating the minimum oil threshold value under different altitudes H aiming at each rotation speed

When the aircraft is in cruise conditionMaintaining the throttle opening of the engineIs always higher than the minimum oil threshold valueSo that the boost pressure P in the cruising state is larger than a third preset value, and the fuel oil supercharging system of the airplane normally runs to cruise normally.

When the airplane is in a cruising state, predicting a fuel temperature allowable value T0 before takeoff to ensure that the fuel temperature T before takeoff is lower than the fuel temperature allowable value T0;

in the flight process, the turbine pressure F is always kept higher than the lowest design value, when the turbine pressure F of the fuel oil pressurization system is higher than a certain pressure value, the fuel oil pressurization system can provide a constant pressurization pressure P for the fuel tank, and when the turbine pressure F is lower than the certain pressure value, the pressurization pressure P is reduced, and the value is the lowest design value;

the airplane mostly runs at a constant rotating speed during cruising, the whole flying working condition is only a plurality of rotating speeds, and the climbing stage is generally a large working condition, so that the adjustment is hardly needed, mainly the control of the cruising working condition is realized, and the airplane can obtain the opening degrees of different accelerators at various rotating speeds n during flying according to the characteristics of an engineThe relationship between the lower altitude H and the boost pressure P is used as a parameter limit set by flight route cruising, and the normal operation of an aircraft fuel oil boosting system can be realized when the aircraft flies in the limit;

taking the third preset value of 20kPa, the turbine pressure F of 30kPa, and the cruising operating condition n of 5000rpm as an example, the minimum throttle limit at different altitudes H can be obtainedAs shown in fig. 2, when the altitude H is about 3500m, the throttle is maintained to be higher than 97.4% in order to keep the pressure after the turbocharger 3 is supercharged, i.e., the turbine pressure F is higher than 30 kPa.

The method further comprises the following steps:

determining the rotating speed of the airplane in the glide state, and respectively calculating the minimum oil threshold value under different altitudes H aiming at each rotating speed

When the airplane is in a gliding state, the throttle opening degree of the engine is keptIs always higher than the minimum oil threshold valueSo that the boost pressure P in the slip-down state is greater than the fourth preset value.

When the airplane is in the glide state, the boost pressure P can be higher than that in the cruise state, and taking the fourth preset value as 10kPa, the turbine pressure F as 15kPa, and the cruise working condition n as 4500rpm as an example, the minimum oil threshold value under different altitudes H can be obtainedThis relationship is another parameter limit established for flight path glideslopes within which flight can cause the aircraft fuel pressurization system to operate properly. The same applies to the aircraft climbing process, and the aircraft generally has a larger throttle state during climbing, and rarely encounters the condition of insufficient supercharging pressure.

Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.