A method for displaying the remaining oxygen supply time of an aircraft

Abstract

This application belongs to the technical field of aircraft oxygen / life support system design. It is a method for displaying the remaining oxygen supply time of an aircraft. It receives the temperature and pressure information uploaded by the oxygen source pressure sensor, calculates the oxygen compression factors at the original pressure and temperature of two groups of high-pressure oxygen cylinders respectively, then calculates the oxygen compression factor under normal conditions, and then calculates the corrected pressures of the two groups of high-pressure oxygen cylinders according to the oxygen compression factor under normal conditions. It calculates the remaining oxygen supply flow according to the corrected oxygen source pressure and the low-pressure warning pressure of the oxygen source, obtains the cabin temperature and cabin pressure sent by the aircraft environmental control system, then calculates the inspiratory volume of each crew member under NTPD conditions according to the inspiratory volume of each crew member under BTPS conditions, obtains the total volume of the two groups of high-pressure oxygen cylinders, and calculates the remaining oxygen supply time according to the inspiratory volume of each crew member under NTPD conditions, the number of crew members and each correction coefficient. The calculation time is short and the calculation is accurate, which is convenient for the crew to check.

Description

Technical Field

[0001] This application belongs to the technical field of aircraft oxygen / life support system design, and particularly relates to a method for displaying the remaining oxygen supply time of an aircraft. Background Technique

[0002] The aircraft oxygen / life support system is used to provide oxygen supply that meets the physiological needs of pilots, achieve low-pressure protection, and prevent pilots from suffering from hypoxia symptoms caused by insufficient partial pressure of inhaled gaseous oxygen. In civil aircraft and transport aircraft, high-pressure oxygen cylinders are generally used as the oxygen source. In combat aircraft, molecular sieve oxygen concentrators are used to generate oxygen, and high-pressure oxygen cylinders are used as backup oxygen sources, which are used when the molecular sieve oxygen concentrator fails or the cabin altitude exceeds 8 km. If only the oxygen pressure in the high-pressure gas cylinder is collected and the temperature is not collected, with the change of the flight environment temperature, the pressure fluctuation range can reach 10%. Therefore, current aircraft collect both the oxygen pressure and temperature in the high-pressure gas cylinder. The main function is to correct the oxygen pressure to the pressure under normal conditions (21.1 °C) because in most cases, the main performance parameters in the oxygen system such as pressure, available oxygen amount, oxygen flow rate, etc. are in the normal state. Currently, the oxygen source display on the aircraft is the oxygen pressure corrected to the normal state. However, for flight crew, a more intuitive display should be the remaining oxygen supply time, which is related to multiple parameters such as oxygen pressure, cabin altitude, and residual pressure state.

[0003] Therefore, how to accurately display the remaining oxygen supply time of the aircraft oxygen source is a problem that needs to be solved. Summary of the Invention

[0004] The purpose of this application is to provide a method for displaying the remaining oxygen supply time of an aircraft to solve the problem in the prior art that the remaining oxygen supply time of the aircraft oxygen source is not displayed.

[0005] The technical solution of this application is: A method for displaying the remaining oxygen supply time of an aircraft, including:

[0006] Receiving the temperature and pressure information uploaded by the oxygen source pressure sensor, and the calculation unit calculates the oxygen compression factors at the original pressure and temperature of two groups of high-pressure oxygen cylinders respectively. The two groups of high-pressure oxygen cylinders are the first high-pressure oxygen cylinder and the second high-pressure oxygen cylinder;

[0007] The calculation unit calculates the oxygen compression factor under normal conditions;

[0008] Calculating the corrected pressures of the two groups of high-pressure oxygen cylinders according to the oxygen compression factor under normal conditions;

[0009] Calculating the corrected oxygen source corrected pressure and uploading the oxygen source corrected pressure to the electromechanical management computer;

[0010] The electromechanical management computer calculates the remaining oxygen supply flow rate based on the oxygen source correction pressure and the oxygen source low-pressure alarm pressure;

[0011] The electromechanical management computer obtains the cabin temperature and cabin pressure sent by the aircraft environmental control system;

[0012] The electromechanical management computer calculates the inspiratory volume of each crew member in the NTPD state based on the cabin temperature, cabin pressure, and the inspiratory volume of each crew member in the BTPS state;

[0013] The electromechanical management computer obtains the total volume of two groups of high-pressure oxygen cylinders, and calculates the remaining oxygen supply time based on the inspiratory volume of each crew member in the NTPD state, the number of crew members, and each correction factor.

[0014] Preferably, the oxygen compression factor Z of the first high-pressure oxygen cylinder 原始a is:

[0015]

[0016] T 原始a ——The temperature of the medium in the first high-pressure oxygen cylinder; P 原始a ——The pressure of the medium in the first high-pressure oxygen cylinder;

[0017] The oxygen compression factor Z of the second high-pressure oxygen cylinder 原始b is:

[0018]

[0019] T 原始b ——The temperature of the medium in the second high-pressure oxygen cylinder; P 原始b ——The pressure of the medium in the second high-pressure oxygen cylinder.

[0020] Preferably, the oxygen compression factor Z in the normal state 修正 is:

[0021]

[0022] T 正常 ——The temperature in the normal state, 294.3K (21.1°C);

[0023] P 正常 ——The atmospheric pressure in the normal state, 101.1 kPa.

[0024] Preferably, the calculation method of the correction pressure P of the first high-pressure oxygen cylinder 修正a and the correction pressure P of the second high-pressure oxygen cylinder 修正b is:

[0025]

[0026] Preferably, the corrected pressure P of the oxygen source 修正 is calculated as follows:

[0027]

[0028] Preferably, the remaining oxygen supply flow rate L of the oxygen source 剩余 is calculated as follows:

[0029]

[0030] P alarm — the low-pressure alarm pressure of the oxygen source, L cylinder — the total volume of the first high-pressure oxygen cylinder and the second high-pressure oxygen cylinder;

[0031] The inhalation flow rate Q per crew member under the NTPD state 正常 is:

[0032]

[0033] Q 正常 — the inhalation volume under the NTPD state; Q 身体 — the inhalation volume under the BTPS state is 15 L / min; P 座舱 — the cabin pressure; T 身体 — the temperature around the body, which can be taken as the cabin temperature; T 正常 — the temperature under the normal state;

[0034] The remaining oxygen supply time t 剩余 is:

[0035]

[0036] wherein, A — safety factor; B — residual pressure correction factor, C — crew number correction factor, N — number of crew members.

[0037] A method for displaying the remaining oxygen supply time of an aircraft according to the present application receives the temperature and pressure information uploaded by the oxygen source pressure sensor, calculates the oxygen compression factors at the original pressures and temperatures of the two groups of high-pressure oxygen cylinders respectively, then calculates the oxygen compression factor under the normal state, and then calculates the corrected pressures of the two groups of high-pressure oxygen cylinders according to the oxygen compression factor under the normal state. The remaining oxygen supply flow rate is calculated according to the corrected pressure of the oxygen source and the low-pressure alarm pressure of the oxygen source. The cabin temperature and cabin pressure sent by the aircraft environmental control system are obtained, and then the inhalation volume per crew member under the NTPD state is calculated according to the inhalation volume per crew member under the BTPS state. The total volume of the two groups of high-pressure oxygen cylinders is obtained. According to the inhalation volume per crew member under the NTPD state, the number of crew members and each correction factor, the remaining oxygen supply time is calculated. The calculation time is short and the calculation is accurate, which is convenient for the crew to check. The remaining oxygen supply time can be displayed in real time on the main display of the aircraft. Brief Description of the Drawings

[0038] To more clearly illustrate the technical solutions provided in this application, the drawings will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application.

[0039] Figure 1 It is a schematic diagram of the overall process of this application;

[0040] Figure 2 It is a schematic diagram of the overall structure of this application.

[0041] 1. First high-pressure oxygen cylinder; 2. Second high-pressure oxygen cylinder; 3. First pressure acquisition module; 4. Second pressure acquisition module; 5. Temperature acquisition module; 6. Solving unit; 7. Electromechanical management computer; 8. Display control processor; 9. Main display. Detailed Embodiment

[0042] To make the purpose, technical solutions, and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the drawings in the embodiments of this application.

[0043] A method for displaying the remaining oxygen supply time of an aircraft, as Figure 1-2 shown, taking the life support system as an example for illustration: The life support system includes a first high-pressure oxygen cylinder 1, a second high-pressure oxygen cylinder 2, a first pressure acquisition module 3, a second pressure acquisition module 4, and a temperature acquisition module 5. The first pressure acquisition module 3 and the second pressure acquisition module 4 are used to respectively acquire the pressures in the first high-pressure oxygen cylinder 1 and the second high-pressure oxygen cylinder 2, and the temperature acquisition module 5 is used to acquire the cabin temperature.

[0044] This application additionally sets up a solving unit 6, an electromechanical management computer 7, and a display control processor 8 for calculating and displaying the remaining oxygen supply time. The solving unit 6, the electromechanical management computer 7, and the display control processor 8 are connected through a bus, and the display control processor 8 is connected to the main display 9 through a bus. The specific steps are as follows:

[0045] Step S100, receive the temperature and pressure information uploaded by the oxygen source pressure sensor, and the solving unit calculates the oxygen compression factors at the original pressures and temperatures of the two groups of high-pressure oxygen cylinders respectively. The two groups of high-pressure oxygen cylinders are the first high-pressure oxygen cylinder and the second high-pressure oxygen cylinder;

[0046] The oxygen compression factor Z of the first high-pressure oxygen cylinder 原始a is:

[0047]

[0048] T 原始a—— Temperature of the medium in the first high-pressure oxygen cylinder; P 原始a —— Pressure of the medium in the first high-pressure oxygen cylinder

[0049] Oxygen compressibility factor Z of the second high-pressure oxygen cylinder 原始b is:

[0050]

[0051] T 原始b —— Temperature of the medium in the second high-pressure oxygen cylinder; P 原始b —— Pressure of the medium in the second high-pressure oxygen cylinder

[0052] Step S200, the calculation unit calculates the oxygen compressibility factor under normal conditions

[0053] Oxygen compressibility factor Z under normal conditions 修正 is:

[0054]

[0055] T 正常 —— Temperature under normal conditions, 294.3K (21.1 °C);

[0056] P 正常 —— Atmospheric pressure under normal conditions, 101.1 kPa;

[0057] By comparing the oxygen compressibility factor in the initial state with that under normal conditions, it serves as the basis for accurately calculating the corrected pressure of the high-pressure oxygen cylinder

[0058] Step S300, calculate the corrected pressures of the two groups of high-pressure oxygen cylinders according to the oxygen compressibility factor under normal conditions

[0059] Corrected pressure P of the first high-pressure steel cylinder 修正a and corrected pressure P of the second high-pressure oxygen cylinder 修正b The calculation methods are:

[0060]

[0061] After obtaining the corrected pressure, the inhalation flow rate of the crew members and the remaining oxygen supply flow rate of the oxygen source can be calculated

[0062] Step S400, calculate the corrected oxygen source corrected pressure and upload the oxygen source corrected pressure to the electromechanical management computer 7

[0063] Oxygen source corrected pressure P 修正 The calculation method is:

[0064]

[0065] Step S500, the electromechanical management computer calculates the remaining oxygen supply flow rate based on the oxygen source correction pressure and the oxygen source low-pressure alarm pressure;

[0066] The remaining oxygen supply flow rate is:

[0067]

[0068] P alarm — the oxygen source low-pressure alarm pressure, L cylinder — the total volume of the first high-pressure oxygen cylinder and the second high-pressure oxygen cylinder;

[0069] The electromechanical management computer obtains the cabin temperature and cabin pressure sent by the aircraft environmental control system, which serves as the basis for accurately calculating the inhalation volume of each crew member in the NTPD state.

[0070] Step S600, calculate the inhalation volume of each crew member in the NTPD state based on the cabin temperature, cabin pressure, and the inhalation volume of each crew member in the BTPS state;

[0071] The inhalation flow rate Q of each crew member in the NTPD state 正常 is:

[0072]

[0073] where Q 正常 — the inhalation volume in the NTPD state; Q 身体 — the inhalation volume in the BTPS state, 15 L / min; P 座舱 — the cabin pressure; T 身体 — the temperature around the body, and T 座 cabin can be taken;

[0074] Step S700, obtain the total volume of the two groups of high-pressure oxygen cylinders, and calculate the remaining oxygen supply time based on the inhalation volume of each crew member in the NTPD state, the number of crew members, and each correction factor;

[0075] The calculation of the remaining oxygen supply time t 剩余 is:

[0076]

[0077] where A — safety factor, 1.1; B — residual pressure correction factor, 1.1 in the safe residual pressure state and 1.2 in the pressure oxygen supply state; C — crew number correction factor, 1.20 for 1 person, 1.10 for 2 people, 1.06 for 3 people, 1.03 for 4 people, 1.02 for 5 people; N — the number of crew members.

[0078] After the electromechanical management computer 7 uploads the remaining oxygen supply time t remaining to the display control processor 8, it is displayed on the main display 9.

[0079] This application first receives the cabin pressure and cabin temperature sent by the flight environmental control system in the initial state, calculates the oxygen compression factor of the high-pressure oxygen cylinder in the initial state, then calculates the oxygen compression factor in the normal state based on the cabin temperature in the normal state, calculates the corrected pressure according to the ratio of the two oxygen compression factors, and then combines the total volume of the high-pressure oxygen cylinder, the NTPD state and the BTPS state to calculate the remaining oxygen supply flow rate of the oxygen source and the inhalation flow rate of each crew member in the NTPD state, and then calculates the remaining oxygen supply time. The calculation time is short and the calculation is accurate, which is convenient for the crew to consult. The remaining oxygen supply time can be displayed in real time on the main display 9 of the aircraft. The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in this application should be covered by the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

[0080] This application receives the temperature and pressure information uploaded by the oxygen source pressure sensor, calculates the oxygen compression factors of the two groups of high-pressure oxygen cylinders at the original pressure and temperature respectively, then calculates the oxygen compression factor in the normal state, calculates the corrected pressures of the two groups of high-pressure oxygen cylinders according to the oxygen compression factor in the normal state, calculates the remaining oxygen supply flow rate according to the corrected oxygen source pressure and the low-pressure alarm pressure of the oxygen source, obtains the cabin temperature and cabin pressure sent by the aircraft environmental control system, then calculates the inhalation volume of each crew member in the NTPD state according to the inhalation volume of each crew member in the BTPS state, obtains the total volume of the two groups of high-pressure oxygen cylinders, and calculates the remaining oxygen supply time according to the inhalation volume of each crew member in the NTPD state, the number of crew members and each correction coefficient. The calculation time is short and the calculation is accurate, which is convenient for the crew to consult. The remaining oxygen supply time can be displayed in real time on the main display of the aircraft. The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in this application should be covered by the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

Claims

1. A method for displaying the remaining oxygen supply time of an aircraft, characterized in that, including: Receiving the temperature and pressure information uploaded by the oxygen source pressure sensor, and the calculation unit calculates the oxygen compression factors at the original pressures and temperatures of two groups of high-pressure oxygen cylinders, namely the first high-pressure oxygen cylinder and the second high-pressure oxygen cylinder; The calculation unit calculates the oxygen compression factor under normal conditions; Calculating the corrected pressures of the two groups of high-pressure oxygen cylinders according to the oxygen compression factor under normal conditions; Calculating the corrected oxygen source pressure after correction and uploading the corrected oxygen source pressure to the electromechanical management computer; The electromechanical management computer calculates the remaining oxygen supply flow rate based on the corrected oxygen source pressure and the low-pressure alarm pressure of the oxygen source; The electromechanical management computer obtains the cabin temperature and cabin pressure sent by the aircraft environmental control system; The electromechanical management computer calculates the inspiratory volume of each crew member under NTPD conditions based on the cabin temperature, cabin pressure, and inspiratory volume of each crew member in the BTPS state; The electromechanical management computer obtains the total volume of the two groups of high-pressure oxygen cylinders, and calculates the remaining oxygen supply time based on the inspiratory volume of each crew member under NTPD conditions, the number of crew members, and various correction factors.

2. The method for displaying the remaining oxygen supply time of an aircraft according to claim 1, wherein, The oxygen compressibility factor Z of the first high-pressure oxygen cylinder 原始a is as follows: T 原始a —— Temperature of the medium in the first high-pressure oxygen cylinder; P 原始a —— Pressure of the medium in the first high-pressure oxygen cylinder; The oxygen compressibility factor Z of the second high-pressure oxygen cylinder 原始b is as follows: T 原始b —— Medium temperature in the second high-pressure oxygen cylinder; P 原始b —— Medium pressure in the second high-pressure oxygen cylinder.

3. The method for displaying the remaining oxygen supply time of an aircraft according to claim 2, wherein, The oxygen compressibility factor under the normal state is Z 正常 : T 正常 —— Temperature under normal conditions, 294.3 K (21.1 °C); P 正常 —— Atmospheric pressure under normal conditions, 101.1 kPa.

4. The method for displaying the remaining oxygen supply time of an aircraft according to claim 3, wherein, The corrected pressure P of the first high-pressure oxygen cylinder 修正a and the corrected pressure P of the second high-pressure oxygen cylinder 修正b are calculated as follows: 。 5. The method for displaying the remaining oxygen supply time of an aircraft according to claim 4, wherein The corrected pressure P of the oxygen source 修正 is calculated as follows:

6. The method for displaying the remaining oxygen supply time of an aircraft according to claim 5, wherein, The remaining oxygen supply flow rate L of the oxygen source 剩余 is calculated as follows: P 告警 —— Low-pressure warning pressure of oxygen source, L 气瓶 —— Total volume of the first high-pressure oxygen cylinder and the second high-pressure oxygen cylinder; The inspiratory flow rate Q of each crew member in the NTPD state 正常 is as follows: Q 正常 —— Inspiratory volume under NTPD condition; Q 身体 —— Inspiratory volume under BTPS condition, 15 L / min; P 座舱 —— Cabin pressure; T 身体 —— Temperature around the body, which can be taken as the cabin temperature; The remaining oxygen supply time t 剩余 is as follows: Wherein, A - safety factor; B - residual pressure correction factor, C - crew number correction factor, N - number of crew members.

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