Oxygen concentration measuring device of inerting system

Abstract

The utility model discloses an oxygen concentration measuring device of an inerting system, which comprises an oxygen partial pressure sensor, a pressure sensor, a signal processing module, a pressure reducing component (1) arranged at the gas inlet end of the oxygen concentration measuring device and used for reducing the gas pressure to a preset pressure value, and a sizing hole (2) arranged at the gas outlet end of the oxygen concentration measuring device, and a filter screen (3) is arranged in front of the sizing hole. The pressure reduction assembly is arranged at the gas inlet end, the sizing hole is formed in the gas outlet end, the oxygen concentration measurement precision of nitrogen-rich gas in an inerting system can be improved, the filter screen is arranged in front of the sizing hole, and dust in a cabin can be prevented from entering the device from the gas outlet end and being attached to the oxygen partial pressure sensor when the oxygen concentration measurement device stands. And the service life of the oxygen partial pressure sensor in the oxygen concentration measuring device can be prolonged.

Description

Technical Field

[0001] The utility model belongs to the technical field of aviation airborne inerting, and in particular relates to an oxygen concentration measuring device for an inerting system. Background Art

[0002] Currently, airborne inerting systems are used for fuel tank inerting, using an air separation unit to generate nitrogen-rich gas for tank protection. This system requires measuring the oxygen concentration in the nitrogen-rich gas. Current oxygen concentration measurement systems measure the oxygen pressure in the nitrogen-rich gas using an oxygen partial pressure sensor, then measure the total pressure of the nitrogen-rich gas using a pressure sensor. A signal processing module then calculates the ratio of the oxygen pressure to the total pressure to obtain the current oxygen concentration. However, current oxygen concentration measurement systems suffer from two issues: First, the measurement accuracy of the oxygen partial pressure sensor is low, and it is currently impossible to directly improve the measurement accuracy of the oxygen partial pressure sensor to meet the required oxygen concentration measurement accuracy for nitrogen-rich gas. Second, the oxygen partial pressure sensor has a short service life, requiring regular replacement of the oxygen partial pressure sensor in the oxygen concentration measurement system. Due to the technical limitations of the oxygen partial pressure sensor, improving the accuracy of oxygen concentration measurement in nitrogen-rich gas and extending the service life of the oxygen partial pressure sensor in the oxygen concentration measurement system remain unresolved technical challenges in current airborne inerting system oxygen concentration measurement systems. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide an oxygen concentration measuring device for an inerting system, so as to improve the oxygen concentration measuring accuracy of the oxygen concentration measuring device for an airborne inerting system and to increase the service life of an oxygen partial pressure sensor in the oxygen concentration measuring device.

[0004] The technical problem to be solved by the present invention can be achieved through the following technical solutions. The present invention provides an oxygen concentration measuring device for an inerting system, comprising: a rectangular housing; and a device provided in the rectangular housing:

[0005] Oxygen partial pressure sensor, used to measure the oxygen pressure in nitrogen-rich gas;

[0006] A pressure sensor for measuring the total pressure of the nitrogen-rich gas;

[0007] The signal processing module is used to calculate the ratio of oxygen pressure to total gas pressure to obtain the current oxygen concentration of the gas;

[0008] The rectangular shell surface is provided with:

[0009] The decompression component 1 is provided at the air inlet end of the oxygen concentration measuring device and is used to reduce the gas pressure to a predetermined pressure value;

[0010] The sizing hole 2 is provided at the gas outlet end of the oxygen concentration measuring device, and a filter screen 3 is provided in front of the sizing hole.

[0011] Optionally, the predetermined pressure value is 230 kPa to 300 kPa.

[0012] Optionally, the calibrating hole 2 limits the gas flow rate to 0.2-0.5 L / min.

[0013] Optionally, the calibrating hole 2 limits the gas flow rate to 0.5 L / min.

[0014] Optionally, the pore size of the filter 3 is not greater than 0.5 microns.

[0015] Optionally, the rear end of the calibrating hole 2 is elliptical.

[0016] Optionally, the calibrating hole 2 is elliptical.

[0017] This utility model provides an oxygen concentration measuring device for an inerting system. By providing a pressure-reducing assembly at the air inlet and a sizing hole at the air outlet, the device can improve the accuracy of measuring the oxygen concentration of nitrogen-rich gas in the inerting system. A filter screen is provided in front of the sizing hole to prevent dust from entering the device through the air outlet and adhering to the oxygen partial pressure sensor when the device is stationary, thereby extending the service life of the oxygen partial pressure sensor in the device. Furthermore, by adjusting the pressure-reducing range of the pressure-reducing assembly, the device can be adapted to a wider range of operating conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0019] Figure 1 This is an outline drawing of the oxygen concentration measuring device;

[0020] Description of reference numerals:

[0021] 1-Decompression assembly;

[0022] 2-calibration hole;

[0023] 3-Filter. DETAILED DESCRIPTION

[0024] In order to make the purpose and advantages of the present invention more clearly understood, the present invention is described in detail below with reference to the following embodiments. The following text is only used to describe one or several specific implementations of the present invention and does not strictly limit the scope of protection specifically claimed by the present invention.

[0025] The oxygen concentration measuring device for an inerting system provided by the present invention will be explained below with reference to the accompanying drawings.

[0026] The original onboard inerting system's oxygen concentration measurement device had a calibrated orifice at the inlet end. This orifice limited the gas flow rate to 0.5L / min and reduced the high-pressure nitrogen-rich gas entering the inlet to the same pressure as the cabin air pressure, ensuring the gas pressure within the oxygen concentration measurement device did not exceed the upper tolerance limit of the oxygen partial pressure sensor. Because the measured gas pressure was consistent with cabin pressure, which is lower, the original device's oxygen concentration measurement accuracy was only ±1% (absolute value).

[0027] In order to solve this problem, the utility model provides an oxygen concentration measuring device for an inerting system. Figure 1 This is a diagram of the oxygen concentration measuring device of the present invention. The device comprises an oxygen partial pressure sensor for measuring the oxygen pressure in nitrogen-rich gas; a pressure sensor for measuring the total pressure of the nitrogen-rich gas; and a signal processing module for calculating the ratio of the oxygen pressure to the total pressure to determine the current oxygen concentration of the gas. The device also includes a pressure reducing assembly 1 disposed at the inlet of the oxygen concentration measuring device to reduce the gas pressure to a predetermined value, and a calibrating hole 2 disposed at the outlet of the oxygen concentration measuring device, with a filter 3 disposed in front of the calibrating hole 2.

[0028] The predetermined pressure value is generally 230kPa to 300kPa. The calibrated hole limits the gas flow rate to 0.2 to 0.5L / min. The pore size of the filter is no greater than 0.5 microns.

[0029] In this embodiment, by removing the calibrating hole currently provided at the air inlet end of the oxygen concentration measuring device and adding a calibrating hole 2 with a flow rate of 0.5L / min at the air outlet end of the oxygen concentration measuring device, the gas pressure value in the oxygen concentration measuring device can be kept consistent with the air inlet end. However, at this time, the internal air pressure of the oxygen concentration measuring device is too high, which will cause the oxygen partial pressure sensor to fail. For this reason, a decompression component 1 is added to the air inlet end. The decompression component reduces the air inlet pressure, which is generally 300kPa to 700kPa, to 230kPa to 300kPa. Maintaining the internal air pressure of the oxygen concentration measuring device at 230kPa to 300kPa can improve the measurement accuracy of the oxygen concentration to ±0.25% (absolute value), and the measurement accuracy is not affected by the cabin air pressure. The decompression component 1 can use a commonly used decompression device, and there are no special requirements.

[0030] In addition, adding a filter 3 at the air outlet can prevent dust in the cabin from entering the device and adhering to the oxygen partial pressure sensor when the oxygen concentration measuring device is stationary, thereby increasing the service life of the oxygen partial pressure sensor.

[0031] Optionally, the calibrating hole 2 is an elliptical hole.

[0032] Optionally, the rear end of the calibrating hole 2 is elliptical.

[0033] The above description is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art may make various improvements and modifications without departing from the principles of the present invention, and such improvements and modifications should be considered within the scope of protection of the present invention. Structures, devices, and operating methods not specifically described or explained in this invention shall, unless otherwise specified or limited, be implemented in accordance with conventional means in the art.

Claims

1. An oxygen concentration measuring device for an inerting system, characterized in that: include: Rectangular shell; the rectangular shell is provided with: Oxygen partial pressure sensor, used to measure the oxygen pressure in nitrogen-rich gas; A pressure sensor for measuring the total pressure of the nitrogen-rich gas; The signal processing module is used to calculate the ratio of oxygen pressure to total gas pressure to obtain the current oxygen concentration of the gas; The rectangular shell surface is provided with: A decompression component (1) is provided at the air inlet end of the oxygen concentration measuring device and is used to reduce the gas pressure to a predetermined pressure value; A sizing hole (2) is provided at the gas outlet end of the oxygen concentration measuring device, and a filter screen (3) is provided in front of the sizing hole.

2. The oxygen concentration measuring device for an inerting system according to claim 1, characterized in that: The predetermined pressure value is 230 kPa to 300 kPa.

3. The oxygen concentration measuring device for an inerting system according to claim 1, characterized in that: The calibrated hole (2) limits the gas flow rate to 0.2-0.5 L / min.

4. The oxygen concentration measuring device for an inerting system according to claim 1, characterized in that: The calibrated hole (2) limits the gas flow rate to 0.5 L / min.

5. The oxygen concentration measuring device for an inerting system according to claim 1, characterized in that: The pore size of the filter (3) is no greater than 0.5 microns.

6. The oxygen concentration measuring device for an inerting system according to claim 1, characterized in that: The calibrating hole (2) is elliptical.

7. The oxygen concentration measuring device for an inerting system according to claim 1, characterized in that: The rear end of the calibrating hole (2) is elliptical.

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