Oil mass monitoring method and oil mass monitoring system for indirectly calculating fuel oil by measuring and calculating volume of gas in oil tank

Abstract

The invention relates to an oil mass monitoring method and an oil mass monitoring system for indirectly calculating fuel oil by measuring and calculating the volume of gas in an oil tank. The oil mass monitoring system comprises an oil tank, a piston system, a pressure sensor, a temperature sensor and a processor, wherein a cavity protruding outwards is formed in the upper portion of the oil tank, and the processor is electrically connected with the pressure sensor and the temperature sensor. The pressure sensor and the temperature sensor are arranged in the cavity protruding outwards. The bottom of the cavity is provided with an air-permeable and liquid-permeation-preventing thin film which is isolated from other space in the oil tank. The piston system is arranged above the cavity protruding outwards and is composed of an electric piston pump, a piston, a piston cavity and a spring. Compared with a traditional oil mass monitoring method and a traditional oil mass monitoring system, measurement errors caused by oil shaking and liquid level inclination during aircraft maneuvering can be remarkably reduced, the measurement precision is high, and the oil mass monitoring system has the advantages of being simple in structure, high in reliability and low in cost.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel measurement for aviation aircraft, and in particular to a fuel quantity monitoring method and a fuel quantity monitoring system for indirectly calculating fuel by measuring the internal gas volume of a fuel tank. Background Art

[0002] Aircraft fuel level measurement is crucial in the aviation field. It not only helps pilots determine the flight range and plan missions, but also adjusts the center of gravity of the aircraft to ensure flight safety. At present, capacitive liquid level sensors are widely used in the domestic aviation field. The principle is to use the difference in dielectric constants between air and fuel to measure the liquid level. However, when the aircraft is performing maneuvering flight, such as acceleration and deceleration, large pitch angle flight, and bank angle changes, the oil sloshing and liquid surface tilt in the fuel tank will cause the capacitive liquid level sensor to produce a large measurement error, which seriously affects the accuracy of fuel measurement. In addition, capacitive liquid level sensors have many other problems, such as cumbersome calibration process, high cost, susceptibility to electromagnetic interference, heavy weight and need to be in direct contact with fuel, and accuracy and reliability are prone to decline after long-term use.

[0003] At present, some scholars have studied the use of optical fiber sensors, magnetostrictive sensors and other liquid level measuring instruments to realize aircraft fuel monitoring, and some researchers have used cameras with lasers and structured light equipment to monitor the specific liquid level of the oil, but these methods have complex system structure and control problems and have not yet entered the practical application stage. Therefore, developing a more accurate, simple, reliable and low-cost fuel level monitoring system to replace the existing capacitive liquid level sensor has important practical significance and commercial value. Summary of the invention

[0004] (1) Technical issues to be solved

[0005] In view of the shortcomings of the prior art, the present application provides a fuel quantity monitoring method and a fuel quantity monitoring system for indirectly calculating the fuel by measuring the gas volume inside the fuel tank, so as to solve the problems of the existing measurement system such as large measurement errors caused by aircraft maneuvers, complex system, high cost and difficult maintenance.

[0006] (2) Technical solution

[0007] Specifically, the present application is implemented through the following technical solutions:

[0008] In a first aspect, the present application provides a method for monitoring the amount of fuel that is indirectly calculated by measuring the volume of gas inside a fuel tank. The method is applied to a fuel amount monitoring system, which includes a fuel tank with a cavity protruding outwards on the top, a piston system, a pressure sensor and a temperature sensor, and a processor electrically connected to the pressure sensor and the temperature sensor; the pressure sensor and the temperature sensor are arranged in the cavity protruding outwards; a breathable and liquid-proof film is arranged at the bottom of the cavity protruding outwards to isolate it from other spaces in the fuel tank; the piston system is arranged above the cavity protruding outwards, and is composed of an electric piston pump, a piston, a piston cavity and a spring; the method includes:

[0009] When the spring limits the piston to the top of the piston chamber, the pressure sensor collects the pressure signal in the oil tank, the temperature sensor collects the temperature signal in the oil tank, and the processor uploads the pressure signal and the temperature signal to the onboard computer;

[0010] When the electric piston pump pushes the piston to the bottom of the piston chamber, the pressure sensor collects the pressure signal in the oil tank, the temperature sensor collects the temperature signal in the oil tank, and the processor uploads the pressure signal and the temperature signal to the onboard computer;

[0011] The onboard computer solves the simultaneous equations based on the ideal gas equation:

[0012]

[0013] The volume of gas in the tank can be calculated:

[0014]

[0015] Among them: P1 is when the spring limits the piston to the top of the piston chamber, the pressure sensor collects the pressure signal in the oil tank; T1 is when the spring limits the piston to the top of the piston chamber, the temperature sensor collects the temperature signal in the oil tank; P2 is when the electric piston pump pushes the piston to the bottom of the piston chamber, the pressure sensor collects the pressure signal in the oil tank; T2 is when the electric piston pump pushes the piston to the bottom of the piston chamber, the temperature sensor collects the temperature signal in the oil tank; V is the volume of gas in the oil tank; V0 is the volume of the piston chamber.

[0016] The fuel volume can then be calculated:

[0017]

[0018] Wherein: P1 is when the spring limits the piston to the top of the piston chamber, the pressure sensor collects the pressure signal in the oil tank; T1 is when the spring limits the piston to the top of the piston chamber, the temperature sensor collects the temperature signal in the oil tank; P2 is when the electric piston pump pushes the piston to the bottom of the piston chamber, the pressure sensor collects the pressure signal in the oil tank; T2 is when the electric piston pump pushes the piston to the bottom of the piston chamber, the temperature sensor collects the temperature signal in the oil tank; V is the gas volume in the oil tank; V0 is the piston chamber volume; V 燃油 V is the volume of fuel in the fuel tank; 油箱 is the fuel tank capacity.

[0019] Finally, the onboard computer outputs the calculated fuel volume value to the fuel quantity indicator for the pilot to read. The entire process is performed continuously and periodically when the fuel quantity monitoring system is powered on, ensuring that the fuel quantity indication is real-time and accurate.

[0020] The second aspect of the present application provides an oil quantity monitoring system for indirectly calculating the fuel by measuring the gas volume inside the oil tank, the oil quantity monitoring system comprising an oil tank with an outwardly protruding cavity on the top, a piston system, a pressure sensor, a temperature sensor, and a processor electrically connected to the pressure sensor and the temperature sensor; the pressure sensor and the temperature sensor are arranged in the outwardly protruding cavity; a breathable and liquid-proof film is arranged at the bottom of the outwardly protruding cavity to isolate it from other spaces in the oil tank; the piston system is arranged above the outwardly protruding cavity, and is composed of an electric piston pump, a piston, a piston cavity and a spring;

[0021] When the spring limits the piston to the top of the piston chamber, the pressure sensor collects the pressure signal in the oil tank, the temperature sensor collects the temperature signal in the oil tank, and the processor uploads the pressure signal and the temperature signal to the onboard computer;

[0022] When the electric piston pump pushes the piston to the bottom of the piston chamber, the pressure sensor collects the pressure signal in the oil tank, the temperature sensor collects the temperature signal in the oil tank, and the processor uploads the pressure signal and the temperature signal to the onboard computer;

[0023] The onboard computer calculates the fuel volume based on a built-in algorithm:

[0024]

[0025] Wherein: P1 is when the spring limits the piston to the top of the piston chamber, the pressure sensor collects the pressure signal in the oil tank; T1 is when the spring limits the piston to the top of the piston chamber, the temperature sensor collects the temperature signal in the oil tank; P2 is when the electric piston pump pushes the piston to the bottom of the piston chamber, the pressure sensor collects the pressure signal in the oil tank; T2 is when the electric piston pump pushes the piston to the bottom of the piston chamber, the temperature sensor collects the temperature signal in the oil tank; V0 is the volume of the piston chamber; V 燃油 V is the volume of fuel in the fuel tank; 油箱 is the fuel tank capacity.

[0026] Finally, the onboard computer outputs the calculated fuel volume value to the fuel quantity indicator for the pilot to read. The entire process is performed continuously and periodically when the fuel quantity monitoring system is powered on, ensuring that the fuel quantity indication is real-time and accurate.

[0027] (3) Beneficial effects

[0028] The oil quantity monitoring method and system provided in this application indirectly calculate the fuel quantity by measuring the gas volume in the fuel tank. This method is based on the ideal gas equation, and measures the gas pressure and temperature changes to obtain the gas volume in the fuel tank, and then indirectly calculates the oil quantity, effectively avoiding the error caused by directly measuring the oil volume. Especially when the aircraft is maneuvering, it can significantly reduce the measurement error caused by oil shaking and liquid level tilt, ensuring the accuracy of oil quantity measurement.

[0029] Compared with traditional measurement systems, this system does not require complex capacitance, image or laser measurement devices. It is mainly composed of a fuel tank, a piston system and simple pressure and temperature sensors. It has a simple structure and reduces system complexity. At the same time, the system is light and small, which is easy to install in the limited space of the aircraft tank and will not add too much extra burden to the aircraft. In addition, since the system components are simple, there is no need for a large number of complex sensors and high-precision measurement equipment, which reduces the manufacturing cost and is conducive to its wide application in the aviation field. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0031] Figure 1 A cross-sectional view of an oil quantity monitoring system provided by an embodiment of the present application, in which the piston is in an uncompressed state;

[0032] Figure 2 A cross-sectional view of an oil level monitoring system provided by an embodiment of the present application, in which the piston is in a fully compressed state;

[0033] Figure 3 A schematic diagram of the structure of the oil level monitoring system provided in the embodiment of the present application;

[0034] Figure 4 A flow chart of the oil level monitoring method provided in an embodiment of the present application.

[0035] Description of the Figures in the Specification:

[0036] 1. Piston system; 2. Electric piston pump; 3. Piston; 4. Piston chamber; 5. Spring; 6. Pressure sensor; 7. Temperature sensor; 8. Outwardly protruding cavity; 9. Breathable and liquid-proof film; 10. Fuel tank; 11. Oil outlet pipe; 12. Fuel tank vent pipe. DETAILED DESCRIPTION

[0037] In order to better explain the present invention and facilitate understanding, the technical solutions and effects of the present invention are described in detail below in conjunction with the accompanying drawings through specific implementation methods. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0038] Please refer to Figure 1 , Figure 2 and Figure 3 ,in Figure 1 A cross-sectional view of an oil quantity monitoring system provided by an embodiment of the present application, in which the piston is in an uncompressed state; Figure 2 A cross-sectional view of an oil level monitoring system provided by an embodiment of the present application, in which the piston is in a fully compressed state; Figure 3 A schematic diagram of the structure of the oil level monitoring system provided in the embodiment of the present application; Figure 4 A flow chart of the oil level monitoring method provided in an embodiment of the present application.

[0039] like Figure 1 , Figure 2 and Figure 3The method and system for monitoring the amount of fuel which is indirectly calculated by measuring the volume of gas inside the fuel tank are shown, comprising a fuel tank 10 with a cavity 8 protruding outwardly arranged on the top, a piston system 1, a pressure sensor 6 and a temperature sensor 7, and a processor (not shown) electrically connected to the pressure sensor 6 and the temperature sensor 7; the pressure sensor 6 and the temperature sensor 7 are arranged in the cavity 8 protruding outwardly; a film 9 which is breathable and liquid-proof is arranged at the bottom of the cavity 8 protruding outwardly to isolate it from other spaces in the fuel tank 10; the piston system 1 is arranged above the cavity 8 protruding outwardly, and is composed of an electric piston pump 2, a piston 3, a piston cavity 4 and a spring 5; the upper side of the piston cavity 4 is connected to the fuel tank ventilation pipe 12; and an oil outlet pipe 11 is arranged at the bottom of the fuel tank 10.

[0040] Example 1

[0041] like Figure 1 As shown, when the spring 5 restricts the piston 3 to the top of the piston chamber 4, the oil tank vent pipe 12 is connected to the oil tank 10. At this time, the pressure inside and outside the oil tank 10 is balanced to prevent deformation due to pressure difference. The pressure sensor 6 collects the pressure signal P1 in the oil tank 10; the temperature sensor 7 collects the temperature signal T1 in the oil tank 10. The processor (not shown) electrically connected to the pressure sensor 6 and the temperature sensor 7 uploads the pressure signal P1 and the temperature signal T1 to the onboard computer (not shown).

[0042] Example 2

[0043] like Figure 2 As shown, when the electric piston pump 2 pushes the piston 3 to the bottom of the piston chamber 4, the fuel tank vent pipe 12 is disconnected from the fuel tank 10. At this time, the amount of gas in the fuel tank 10 remains unchanged, and the pressure and temperature will change due to the compression of the gas volume. The pressure sensor 6 collects the pressure signal P2 in the fuel tank 10; the temperature sensor 7 collects the temperature signal T2 in the fuel tank 10. The processor (not shown) electrically connected to the pressure sensor 6 and the temperature sensor 7 uploads the pressure signal P2 and the temperature signal T2 to the onboard computer (not shown). The onboard computer (not shown) calculates the fuel volume V according to the built-in algorithm. 燃油 , and output to the oil level indicator (not shown).

[0044] Example 3

[0045] Figure 4 For the flow chart of the oil volume monitoring method provided in this application, please refer to Figure 4The oil quantity monitoring method provided in this embodiment is applied to an oil quantity monitoring system, wherein the oil quantity monitoring system comprises an oil tank with an outwardly protruding cavity on the top, a piston system, a pressure sensor, a temperature sensor, and a processor electrically connected to the pressure sensor and the temperature sensor; the pressure sensor and the temperature sensor are arranged in the outwardly protruding cavity; a breathable and liquid-proof film is arranged at the bottom of the outwardly protruding cavity to isolate it from other spaces in the oil tank; the piston system is arranged above the outwardly protruding cavity and consists of an electric piston pump, a piston, a piston cavity and a spring; the method comprises:

[0046] S401, in the initial state of the system, the piston is located at the top of the piston chamber, the oil tank vent pipe is connected to the oil tank, and the gas state in the oil tank is consistent with the outside. The pressure sensor collects pressure signals, and the temperature sensor collects temperature signals.

[0047] S402: A processor electrically connected to the pressure sensor and the temperature sensor uploads the pressure signal and the temperature signal to the onboard computer.

[0048] S403: When the electric piston pump pushes the piston to the bottom of the piston chamber, the oil tank vent pipe is disconnected from the oil tank. At this time, the amount of gas in the oil tank remains unchanged, and the pressure and temperature change due to the compression of the gas volume. The pressure sensor collects pressure signals, and the temperature sensor collects temperature signals.

[0049] S404: The processor electrically connected to the pressure sensor and the temperature sensor uploads the pressure signal and the temperature signal to the onboard computer.

[0050] S405, the onboard computer uses a built-in algorithm:

[0051]

[0052] Wherein: P1 is when the spring limits the piston to the top of the piston chamber, the pressure sensor collects the pressure signal in the oil tank; T1 is when the spring limits the piston to the top of the piston chamber, the temperature sensor collects the temperature signal in the oil tank; P2 is when the electric piston pump pushes the piston to the bottom of the piston chamber, the pressure sensor collects the pressure signal in the oil tank; T2 is when the electric piston pump pushes the piston to the bottom of the piston chamber, the temperature sensor collects the temperature signal in the oil tank; V0 is the volume of the piston chamber; V 燃油 V is the volume of fuel in the fuel tank; 油箱 is the fuel tank capacity.

[0053] The specific value of the fuel volume is calculated and output to the fuel quantity indicator.

[0054] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A fuel quantity monitoring system for indirectly calculating fuel by measuring the gas volume inside the fuel tank, characterized in that: The oil level monitoring system includes an oil tank with an outwardly protruding cavity on the top, a piston system, a pressure sensor and a temperature sensor, and a processor electrically connected to the pressure sensor and the temperature sensor; the pressure sensor and the temperature sensor are arranged in the outwardly protruding cavity; a breathable and liquid-proof film is arranged at the bottom of the outwardly protruding cavity to isolate it from other spaces in the oil tank; the piston system is arranged above the outwardly protruding cavity, and consists of an electric piston pump, a piston, a piston cavity and a spring.

2. The fuel quantity monitoring system for indirectly calculating the fuel by measuring the gas volume inside the fuel tank according to claim 1, characterized in that: The outwardly protruding cavity arranged above the fuel tank is a part of the fuel tank, and the overall volume of the fuel tank includes the volume of the outwardly protruding cavity. An oil outlet pipe is arranged at the bottom of the fuel tank and is connected to the engine system.

3. The fuel quantity monitoring system for indirectly calculating the fuel by measuring the gas volume inside the fuel tank according to claim 1, characterized in that: The piston system consists of an electric piston pump, a piston, a piston chamber and a spring. The electric piston pump pushes the piston downward to the bottom of the piston chamber, and the spring pushes the piston upward to the top of the piston chamber. An oil tank ventilation pipe is provided on the upper side of the piston chamber. When the piston is located at the top of the piston chamber, the oil tank ventilation pipe is connected to the oil tank. When the electric piston pump pushes the piston to the bottom of the piston chamber, the oil tank ventilation pipe is disconnected from the oil tank.

4. The fuel quantity monitoring system for indirectly calculating the fuel by measuring the gas volume inside the fuel tank according to claim 1, characterized in that: The pressure sensor and temperature sensor are highly sensitive and high-precision sensing devices, which can accurately measure the required pressure and temperature signals within a short time after the pressure and temperature in the oil tank change.

5. The fuel quantity monitoring system for indirectly calculating the fuel quantity by measuring the gas volume inside the fuel tank according to claim 1, characterized in that: The processor electrically connected to the pressure sensor and the temperature sensor has its other end connected to an onboard computer. The onboard computer uses the pressure and temperature signals uploaded by the processor and calculates the fuel volume according to a built-in algorithm.

6. The fuel quantity monitoring system for indirectly calculating the fuel quantity by measuring the internal gas volume of the fuel tank according to claim 1, characterized in that: The air-permeable and liquid-proof film is arranged at the bottom of the cavity protruding outwards, and is isolated from other spaces in the oil tank, so as to prevent the oil from contaminating the sensor and causing measurement errors.

7. A method for monitoring the amount of fuel by indirectly calculating the volume of gas inside a fuel tank, characterized in that The following steps are involved: Step 1) In the initial state of the system, the piston is located at the top of the piston chamber, at which time the oil tank vent pipe is connected to the oil tank, and the gas state in the oil tank is consistent with that in the outside world; the pressure sensor collects a pressure signal, and the temperature sensor collects a temperature signal; Step 2) a processor electrically connected to the pressure sensor and the temperature sensor uploads the pressure signal and the temperature signal to the onboard computer; Step 3) When the electric piston pump pushes the piston to the bottom of the piston chamber, the oil tank vent pipe is disconnected from the oil tank. At this time, the amount of gas in the oil tank remains unchanged, and the pressure and temperature change due to the compression of the gas volume; the pressure sensor collects the pressure signal, and the temperature sensor collects the temperature signal; Step 4) a processor electrically connected to the pressure sensor and the temperature sensor uploads the pressure signal and the temperature signal to the onboard computer; Step 5) The onboard computer uses a built-in algorithm: Wherein: P1 is when the spring limits the piston to the top of the piston chamber, the pressure sensor collects the pressure signal in the oil tank; T1 is when the spring limits the piston to the top of the piston chamber, the temperature sensor collects the temperature signal in the oil tank; P2 is when the electric piston pump pushes the piston to the bottom of the piston chamber, the pressure sensor collects the pressure signal in the oil tank; T2 is when the electric piston pump pushes the piston to the bottom of the piston chamber, the temperature sensor collects the temperature signal in the oil tank; V0 is the volume of the piston chamber; V 燃油 V is the volume of fuel in the fuel tank; 油箱 is the fuel tank capacity. The specific value of the fuel volume is calculated and output to the fuel quantity indicator.

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