Flight recorder heat flux meter, working method and flight recorder

Abstract

The invention relates to the technical field of aircrafts, and provides a flight recorder heat flux meter, a working method and a flight recorder. According to the method, a heat flux meter is characterized in that one end of a flow metering pipe is used for inputting a medium, the other end of the flow metering pipe is connected with one end of a first temperature metering pipe through a distance-adjustable pipeline fixer, and the other end of the first temperature metering pipe is connected with one port of a flight recorder heat flux test piece; the other port of the flight recorder heat flux test piece is connected with one end of a second temperature metering pipe, the other end of the second temperature metering pipe is connected with one end of a medium discharge pipe through a distance-adjustable pipeline fixer, and the other end of the medium discharge pipe is used for discharging a medium; temperature sensors are arranged in the first temperature metering tube and the second temperature metering tube and are used for detecting the temperature flowing into the flight recorder heat flux test piece and the temperature flowing out of the flight recorder heat flux test piece; and a turbine flowmeter is arranged in the flow metering pipe and is used for detecting the flow of a medium.

Description

Technical Field

[0001] The present invention relates to the technical field of aircraft, and in particular to a flight recorder heat flux meter, a working method and a flight recorder. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] With the development of the aviation industry and the liberalization of the low-altitude economy, the number of aircraft such as light sport vehicles, light aircraft, and eVTOLs will experience rapid growth, placing significant pressure on flight safety regulation. Traditional flight recorders are too large and heavy to meet the requirements of these aircraft, necessitating the design of miniature and compact flight recorders to accommodate these aircraft.

[0004] As a device for recording and protecting flight data, flight recorders must comply with the corresponding Minimum Operating Performance Specifications (MOPS). These devices have strict and clear test requirements for their ability to withstand high-temperature fires. Traditional methods for measuring heat flux during fire tests on flight recorders are restricted by factors such as pipeline insulation conditions, temperature sensor installation locations, and fire test conditions. Consequently, they are unable to accurately measure the heat flux of flight recorders and cannot even be used for fire tests on small-sized flight recorders. Summary of the Invention

[0005] In order to solve the technical problems existing in the above-mentioned background technology, the present invention provides a flight recorder heat flux meter, a working method and a flight recorder. The present invention provides a flight recorder heat flux meter that can be used for heat flux measurement of micro and small flight recorders and can accurately measure heat flux, which is of great significance.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A first aspect of the present invention provides a flight recorder heat flux meter.

[0008] A flight recorder heat flux meter comprises: a first temperature metering tube, a second temperature metering tube, a flow metering tube, an adjustable spacing pipe fixture, a flight recorder heat flux test piece, and a medium discharge pipe.

[0009] One end of the flow metering tube is used to input the medium, the other end of the flow metering tube is connected to one end of the first temperature metering tube via an adjustable-space pipe fixture, the other end of the first temperature metering tube is connected to a port of the flight recorder heat flux test piece, the other port of the flight recorder heat flux test piece is connected to one end of the second temperature metering tube, the other end of the second temperature metering tube is connected to one end of the medium discharge pipe via the adjustable-space pipe fixture, the other end of the medium discharge pipe is used to discharge the medium;

[0010] The first temperature measuring tube and the second temperature measuring tube are both provided with temperature sensors for detecting the temperature of the heat flux flowing into the flight recorder test piece and the temperature of the heat flux flowing out of the flight recorder test piece;

[0011] A turbine flowmeter is provided in the flow metering tube to detect the flow of the medium.

[0012] Furthermore, the first temperature measuring tube and the second temperature measuring tube have the same structure.

[0013] Furthermore, the first temperature measuring tube further comprises: two sections of first tube body, inner protective tube, support frame, first quick pipe joint, tee, sensor wiring harness, outlet pipe joint and first quick pipe joint seat;

[0014] The inner protective tube is fixed to the central axis of the first tube body through a support frame. The end of the inner protective tube close to the flight recorder heat flux test piece is used to fix the temperature sensor. The temperature sensor is connected to the sensor wiring harness, and the sensor wiring harness is placed in the inner protective tube; the end of the inner protective tube close to the adjustable spacing pipeline fixture is provided with a boss for cooperating with the support frame to limit the position; one end of the first quick pipe joint is connected to the first tube body, and the other end of the first quick pipe joint is connected to the flight recorder heat flux test piece; the two ends of the tee are used to connect the two sections of the first tube body, and the third end is connected to the outlet pipe joint. The sensor wiring harness passes through the inner protective tube and the outlet pipe joint; the first quick pipe joint seat is used to connect the first tube body and the flow metering tube.

[0015] Furthermore, a hole is opened on the boss for embedding the inner protective tube section of the outlet pipe joint to form a right-angle bend and limit the position.

[0016] Furthermore, the flow metering tube also includes: a second tube body, a second quick pipe joint, a first reducer tube joint and a third tube body; the second tube body is used to fix the turbine flowmeter, the first reducer tube joint is used to connect the second tube body and the third tube body, and the second quick pipe joint is used to connect the third tube body and the temperature metering tube.

[0017] Furthermore, the diameter of the second tube body is greater than the diameter of the third tube body.

[0018] Furthermore, the adjustable spacing pipe fixture includes a first fixing card, a second fixing card and a slide groove. The first fixing card and the second fixing card have the same structure, and both the first fixing card and the second fixing card slide on the slide groove. By adjusting the distance between the first fixing card and the second fixing card, the device can adapt to flight recorder heat flux test pieces of different dimensions.

[0019] Furthermore, the first tube body passes through a first fixing card, and the first fixing card is used to limit and fix the temperature measuring tube.

[0020] Furthermore, the flight recorder heat flux test piece comprises: a flight recorder proportional housing, a medium baffle, a fixing tube and a second quick pipe joint seat;

[0021] A medium baffle is provided in the flight recorder proportional housing to divide the space inside the flight recorder proportional housing into two parts, so as to isolate the inlet for medium flowing into the flight recorder proportional housing and the outlet for medium flowing out of the flight recorder proportional housing;

[0022] The fixed tube is connected to the second quick tube connector seat, and the flight recorder housing is fixed to the fixed tube through the second quick tube connector seat; the second quick tube connector seat is used to connect the fixed tube and the temperature measuring tube.

[0023] Furthermore, a heat-insulating protective layer is provided on the outer peripheral surface of the fixed pipe to insulate the heat of the fixed pipe.

[0024] Furthermore, the medium discharge pipe includes: a third quick pipe joint, a fourth pipe body, a second reducer pipe joint and a 90° elbow. One end of the third quick pipe joint is connected to the second temperature measuring tube, and the other end is connected to one end of the fourth pipe body. The other end of the fourth pipe body is connected to the second reducer pipe joint, and the second reducer pipe joint is connected to the 90° elbow for discharging the medium.

[0025] A second aspect of the present invention provides an operating method of a flight recorder heat flux meter.

[0026] A working method of a flight recorder heat flux meter, applied to the flight recorder heat flux meter described in the first aspect, comprising:

[0027] The turbine flowmeter in the flow metering tube measures the flow value of the medium and uploads it to the processor;

[0028] The temperature sensor in the first temperature measuring tube collects the inlet temperature value of the heat flux test piece flowing into the flight recorder and uploads it to the processor;

[0029] The temperature sensor in the second temperature measuring tube collects the outlet temperature value of the heat flux test piece flowing out of the flight recorder and uploads it to the industrial computer;

[0030] The industrial computer calculates the temperature difference according to the difference between the outlet temperature value and the inlet temperature value; and calculates the heat flux of the flight recorder according to the flow value, the temperature difference, the specific heat of the medium and the surface area of the flight recorder shell.

[0031] A third aspect of the present invention provides a flight recorder.

[0032] A flight recorder comprises a memory and the flight recorder heat flux meter according to the first aspect connected to the memory.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] The present invention provides a flight recorder heat flux meter, which is used to measure the heat flux of a flight recorder during a high-temperature fire test. The instrument has the characteristics of low requirements on the size of the measured structural parts, high measurement accuracy, and good versatility.

[0035] The present invention directly measures the outlet and inlet temperatures of the flight recorder's proportional housing through a temperature measuring tube, thereby avoiding measurement input errors caused by flame heating of the pipe and simultaneously avoiding damage to the sensor harness and seals through medium protection.

[0036] The present invention designs the length of the fixed tube so that the surface area of the tube section not covered by the thermal insulation protective layer is equal to the surface area of the flight recorder's proportional outer shell blocked by the fixed tube. The fire surface area of the flight recorder's heat flux meter and the fire surface area of the tested flight recorder can be approximately equivalent, thereby improving the accuracy.

[0037] The present invention reduces the sizes of the first tube body, the fixed tube and the thermal insulation protective layer through system design to adapt to smaller-sized flight recorders and reduce measurement errors introduced by the above links.

[0038] The present invention can achieve more accurate and efficient flight recorder heat flux measurement, and is applicable to flight recorders with a minimum diameter or side length of 50 mm, playing an important role in the design and verification of micro and small flight recorders. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0040] Figure 1 1 is a schematic structural diagram of a heat flux meter for a flight recorder according to an embodiment of the present invention;

[0041] Figure 2 Schematic diagram of a fire test system according to an embodiment of the present invention;

[0042] Figure 3 1 is a schematic structural diagram of a temperature measuring tube according to an embodiment of the present invention;

[0043] Figure 4 1 is a schematic structural diagram of a flow metering tube according to an embodiment of the present invention;

[0044] Figure 5 1 is a schematic structural diagram of an adjustable spacing pipe fixture according to an embodiment of the present invention;

[0045] Figure 61 is a schematic structural diagram of a flight recorder heat flux test piece according to an embodiment of the present invention;

[0046] Figure 7 is a top cross-sectional view of a flight recorder heat flux meter according to an embodiment of the present invention;

[0047] Figure 8 is a side sectional view of a medium inlet pipe section shown in an embodiment of the present invention;

[0048] in,

[0049] 1. Temperature measuring tube, 1-1. First tube body, 1-2. Inner protective tube, 1-3. Temperature sensor, 1-4. Support frame, 1-5. First quick pipe joint, 1-6. Tee, 1-7. Sensor wiring harness, 1-8. Outlet pipe joint, 1-9. First quick pipe joint base;

[0050] 2. Flow metering tube, 2-1. Second tube body, 2-2. Turbine flowmeter, 2-3. Second quick pipe joint, 2-4. First reducer pipe joint, 2-5. Third tube body;

[0051] 3. Adjustable spacing pipe fixture, 3-1, first fixing card, 3-2, second fixing card,

[0052] 4. Flight recorder heat flux test piece, 4-1. Flight recorder proportional housing, 4-2. Dielectric baffle, 4-3. Fixed tube, 4-4. Thermal insulation layer, 4-5. Second quick-connect fitting seat;

[0053] 5. Medium discharge pipe, 5-1. Fourth pipe body, 5-2. Third quick pipe joint, 5-3. Second reducer pipe joint, 5-4. 90° elbow;

[0054] 6. Flight recorder heat flux meter, 7. Firewall, 8. First burner, 9. Second burner, 10. Third burner, 11. Burner nozzle, 12. Thermocouple. DETAILED DESCRIPTION

[0055] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0056] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0057] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0058] Example 1

[0059] like Figure 1 As shown, a flight recorder heat flux meter includes: a temperature metering tube 1, a flow metering tube 2, an adjustable spacing pipe fixture 3, a flight recorder heat flux test piece 4 and a medium discharge pipe 5.

[0060] The purpose of a fire test is to verify that the flight recorder meets the designed fire survivability standards. The fire envelope, heat flux, and flame temperature requirements of the corresponding Minimum Operational Performance Specification (MOPS) must be met. Typical requirements include full flame envelope, a heat flux of 158 kW / m², and a flame temperature of 1100°C. A flight recorder heat flux meter is used to measure the heat flux during the fire test. Using a housing identical to the flight recorder under test, the flight recorder fire process is simulated. The collected temperature and flow information is used to calculate the heat flux of the flight recorder under the current flame conditions. This information serves as a basis for adjusting the test environment, such as burner gas flow, air volume, and location distance. Throughout the test environment adjustment process, the flight recorder heat flux meter continuously monitors the heat flux. Once the test environment meets the requirements of the corresponding Minimum Operational Performance Specification (MOPS), the flight recorder under test will be directly replaced with the flight recorder heat flux meter for the fire test to ensure consistent test conditions.

[0061] like Figure 2 As shown, the fire test system includes: a flight recorder heat flux meter 6, a firewall 7, a first burner 8, a second burner 9, a third burner 10, a burner 11, and three thermocouples 12

[0062] The firewall 7 primarily isolates the flames and heat during the fire test, preventing heat absorption in the flight recorder heat flux meter 6 pipeline and protecting sensors such as the flowmeter. The flight recorder heat flux meter 6 is also secured at a specified height above the ground. A mounting and transfer mechanism is provided for the flight recorder under test to replace the flight recorder heat flux meter 6 in situ for testing. The burner generates a high-temperature flame by combusting the gas mixture and spraying it onto the flight recorder under test, with a stable combustion duration of 1.5 hours. The thermocouple 12 ensures uninterrupted temperature measurement throughout the test. The firewall 7 and the burner are placed directly on the ground. Usually, the firewall 7 is fixed and the burner is mobile. The burner can adjust the flame temperature and heat flux by moving the whole burner and setting the height and angle of the burner nozzle 11. The flight recorder heat flux meter 6 is fixed to the firewall 7 through the adjustable spacing fixture 3. The two temperature measuring tubes 1 pass through the firewall 7 along the adjustable spacing fixture 3. The thermocouple 12 is fixed with a fixed bracket, and the temperature monitoring point should be located 25 mm from the center of the flight recorder surface.

[0063] In some embodiments, as Figure 3 As shown, the temperature measuring tube 1 includes: a first tube body 1-1, an inner protective tube 1-2, a temperature sensor 1-3, a support frame 1-4, a first quick pipe joint 1-5, a tee 1-6, a sensor harness 1-7, an outlet pipe joint 1-8 and a first quick pipe joint seat 1-9.

[0064] Specifically, the first tube body 1-1 is used for structural support of the flight recorder heat flux meter and serves as a medium flow pipeline; the inner protective tube 1-2 is a long tube structure fixed to the central axis position of the first tube body 1-1 through the inner ring opening of the support frame 1-4, the tip blind tube is used to fix the temperature sensor 1-3, the middle long tube section is used as a protective container for the sensor harness 1-7, the tail section is thickened and the boss is used to cooperate with the support frame 1-4 for limiting, and the hole on the boss can be embedded in the inner protective tube section of the outlet pipe joint 1-8 to form a right-angle bend and limit; the temperature sensor 1-3 is fixed at the tip blind tube of the inner protective tube 1-2, and is used to collect the inlet or outlet medium temperature of the flight recorder heat flux test piece, and output the temperature signal to the data acquisition module through the sensor harness 1-7; the support frame 1-4 is a hollow structure with inner and outer rings. The inner and outer rings are coaxially fixed with four ribs. The hollow part is used as a medium flow pipeline. The outer ring is fixed to the pipe mouth of the first tube body 1-1 through interference connection and other connection methods. The inner ring opening is used to support the inner protective tube 1-2 and isolate it from the first tube body 1-1 through the flow of medium for temperature sensor 1-3 and The sensor harness 1-7 is protected from fire; the first quick pipe joint 1-5 is connected to the first tube body 1-1 through an internal thread and is used to quickly connect the temperature measuring tube 1 and the flight recorder heat flux test piece 4. The seal is achieved through a labyrinth seal, etc., which reduces the test preparation time and ensures the versatility of the test equipment; the tee 1-6 connects the two sections of the first tube body 1-1 through an internal thread and fixes the outlet pipe joint 1-8 through an internal thread; the sensor harness 1-7 is used for signal transmission of the temperature sensor 1-3, passing through the inner protective tube 1-2 and the outlet pipe joint The cavity of the head 1-8 realizes the external output of the temperature signal; the outlet pipe joint 1-8 is fixed on the tee 1-6 through a thread, and the inner protective tube section is inserted into the tail opening of the inner protective tube 1-2 to form a right-angle elbow for use with the sensor harness 1-7 and limit the inner protective tube 1-2. After the limitation is completed, the glue is injected and fixed; the first quick pipe joint seat 1-9 is connected to the first tube body 1-1 through a thread, and is used to realize the quick pipe joint connection between the temperature measuring tube 1 and other components. The sealing is achieved by a labyrinth seal or the like, which reduces the test preparation time and ensures the versatility of the test equipment.

[0065] In some embodiments, as Figure 4 As shown, the flow metering tube 2 includes: a second tube body 2-1, a turbine flowmeter 2-2, a second quick pipe joint 2-3, a first reducing pipe joint 2-4 and a third tube body 2-5.

[0066] Specifically, the second tube body 2-1 is used to fix the turbine flowmeter 2-2 and provide a metering straight pipe section for the turbine flowmeter 2-2 as a medium flow pipeline; the turbine flowmeter 2-2 is connected to the second tube body 2-1 through a thread, and is used to measure the flow of the medium in the flight recorder heat flux meter; the second quick pipe joint 2-3 is connected to the third tube body 2-5 through an internal thread, and is used to achieve a quick connection between the flow metering tube 2 and the temperature metering tube 1, and achieves sealing through a labyrinth seal or the like, which facilitates flowmeter maintenance and calibration and reduces test preparation time; the first reducer tube joint 2-4 is connected to the second tube body 2-1 and the third tube body 2-5 through a thread, and is used to achieve the connection between two tubes of different sizes; the third tube body 2-5 is fixed to the first reducer tube joint 2-4 through a thread for structural support and serves as a medium flow pipeline.

[0067] In this embodiment, the turbine flowmeter 2 - 2 can be an intelligent turbine flowmeter capable of transmitting signals.

[0068] In some embodiments, as Figure 5 As shown, the adjustable spacing pipeline fixture 3 includes: a first fixing card 3-1 and a second fixing card 3-2.

[0069] Specifically, the first fixing card 3-1 and the second fixing card 3-2 pass through the first tube body 1-1 with the help of two circular fixing holes and use the first quick pipe joint 1-5 and the first quick pipe joint seat 1-9 to limit and fix the temperature measuring tube 1, and the spacing between the two is quickly adjusted through the slide groove between the two, which can be suitable for flight recorder heat flux test pieces 4 of different dimensions. A scale is set at the slide groove position to quickly confirm the axial gap between the two temperature measuring tubes 1 for the installation of the flight recorder heat flux test piece 4.

[0070] In some embodiments, as Figure 6 As shown, the flight recorder heat flux test piece 4 includes: a flight recorder proportional housing 4-1, a medium baffle 4-2, a fixing tube 4-3, a heat insulation protective layer 4-4 and a second quick pipe connector seat 4-5.

[0071] Specifically, the flight recorder proportional shell 4-1 is fixed on the fixed tube 4-3, and is used to accept the state of the simulated flight recorder surrounded by flames when encountering high-temperature fire, and serve as a carrier for independent heat exchange between the medium and the flame as much as possible; the medium baffle 4-2 is located on the symmetrical surface of the flight recorder proportional shell 4-1, and isolates the medium in the flight recorder proportional shell 4-1 according to the inlet and outlet, so that the medium can flow fully inside it and absorb heat evenly; the fixed tube 4-3 is connected to the second quick pipe joint seat 4-5 through a thread, and is used to fix the flight recorder proportional shell 4-1 and serve as a medium flow pipeline; the thermal insulation protective layer 4-4 is fixed to the fixed tube 4-3 after coating or press molding, and is used to insulate the fixed tube 4-3 and reduce the heat exchange between the medium and the flame through the fixed tube 4-3; the second quick pipe joint seat 4-5 is connected to the fixed tube 4-3 through an internal thread, and is used to achieve quick connection with the temperature measuring tube 1, reducing the test preparation time and ensuring the versatility of the test equipment.

[0072] In some embodiments, as Figure 7 、 Figure 8 As shown, the flight recorder heat flux meter, except for the temperature measuring tube 1, which needs to be installed with the adjustable spacing pipe holder 3 during assembly, the other parts can be assembled independently. When assembling the temperature measuring tube 1, do not install the combination of the first tube body 1-1 and the first quick pipe connector seat 1-9 and the 1-5 quick pipe connector first. Pass the first tube body 1-1 on the temperature measuring tube assembly through one of the two concentric holes in the fixing card and complete the installation of the first quick pipe connector 1-5. Then pass the combination of the first tube body 1-1 and the first quick pipe connector seat 1-9 through the other of the two concentric holes in the fixing card. Finally, complete the assembly of the temperature measuring tube 1 through threaded connection. Repeat this step to achieve the connection between the two sets of temperature measuring tubes 1 and the adjustable spacing pipe holder 3; through the second quick The quick-connect fitting 2-3 is docked with the first quick-connect fitting seat 1-9 to connect the flow metering tube 2 and the temperature metering tube 1. The third quick-connect fitting 5-2 is docked with the first quick-connect fitting seat 1-9 to connect the medium discharge tube 5 and the temperature metering tube 1. The two exposed inner protective tubes 1-2 are inserted into the fixed tube 4-3. After the two second quick-connect fitting seats 4-5 are docked with the two first quick-connect fittings 1-5, the inner protective tubes 1-2 are inserted into the interface between the fixed tube 4-3 and the flight recorder housing 4-1, completing the connection between the flight recorder heat flux test piece 4 and the two sets of temperature metering tubes 1. Once all components are connected, the flight recorder heat flux meter is assembled.

[0073] Working principle of flight recorder heat flux meter: Before use, the flight recorder heat flux meter needs to be filled with medium and provide stable pressure to keep the medium flowing inside it. Then the burner is ignited and the flame formed covers the flight recorder proportional shell 4-1 as required and then enters the working state.

[0074] When the flight recorder heat flux meter is measuring, the medium flows into the flow metering tube 2 through the second tube body 2-1. The "medium flow" value is obtained when the medium passes through the turbine flowmeter 2-2. The medium passes through the third tube body 2-5 and the second quick pipe joint 2-3 in sequence before flowing into the temperature metering tube 1. After passing through the tee 1-6, the medium begins to thermally protect the inner protective tube 1-2. The medium passes through the support frame 1-4 and the first quick pipe joint 1-5 in sequence before flowing into the flight recorder heat flux test piece 4. The medium flow enters the flame influence range and begins to absorb heat and heat up. When passing through the fixed tube 4-3, the medium is insulated by the thermal insulation protective layer 4-4 and the temperature rise of the medium is very small. The medium enters the fixed tube 4-3 not covered by the thermal insulation protective layer 4-4 and is connected to the flight recorder proportional shell 4-1 at the inlet position, which is in contact with the temperature sensor 1-3 for temperature measurement to obtain the "inlet temperature" value. At the same time, it begins to absorb heat rapidly. The medium enters the flight recorder isomeric shell 4-1 and absorbs a large amount of heat. At the same time, it is blocked by the medium baffle 4-2 and flows into the gap left by the medium baffle 4-2 and the flight recorder isomeric shell 4-1 and begins to flow toward the outlet position. At the outlet position, it contacts another temperature sensor 1-3 to measure the temperature and obtain the "outlet temperature" value. At the same time, thermal protection of the inner protective tube 1-2 begins. Then, when passing through the fixed tube 4-3, the medium is protected by the thermal insulation layer 4-4, and the medium temperature rise is very small. It flows into the temperature measuring tube 1 through the second quick pipe joint seat 4-5; after passing through the first tube body 1-1 and the first quick pipe joint seat 1-9 in sequence, the medium flows into the medium discharge pipe 5; after passing through the fourth tube body 5-1, the second reducer 5-3, and the 90° elbow 5-4 in sequence, the medium is discharged through the 90° elbow 5-4.

[0075] The temperature sensor outputs 4-20mA analog value, and the turbine flowmeter outputs flow value, which are transmitted to the industrial computer of the fire test system through the 485 interface of the data acquisition module;

[0076] The industrial computer (processor) calculates the heat flux using the "medium flow rate", "inlet temperature" and "outlet temperature" data. The calculation formula for the flight recorder heat flux is as follows:

[0077]

[0078] Where: dT represents the temperature rise of the medium, F represents the flow rate of the medium, SH represents the specific heat of the medium, A represents the surface area of the flight recorder shell, and C represents the absorption constant.

[0079] After the heat flux stabilizes and reaches the test conditions, the flight recorder heat flux meter in the flame is replaced with the flight recorder to ensure that the heat flux of the fire test is the same and start the fire test. At this point, the flight recorder heat flux meter completes the working process.

[0080] The calculation formula for the flight recorder's heat flux indicates that improving heat flux accuracy requires accurate measurement of the medium's temperature rise and flow rate within the flight recorder's proportional housing 4-1. Since the fire test requires the flame to completely enclose the flight recorder's proportional housing 4-1, the flame will inevitably heat the fixed tube 4-3, further increasing the temperature of the medium within the fixed tube 4-3 and affecting the heat flux measurement accuracy. If the fixed tube 4-3 were completely shielded by the thermal insulation layer 4-4, the thermal insulation layer 4-4 would be too thick or too abundant, resulting in a decrease in the exposed surface area at the connection between the flight recorder's proportional housing 4-1 and the fixed tube 4-3, thus affecting the heat flux measurement accuracy.

[0081] The above pain points are particularly prominent when the flight recorder is small in size and uses traditional measurement methods: under the traditional measurement method, temperature measurement uses thermocouples or thermal resistors installed on the outside of the pipe, and the pipe diameter is relatively large. At the same time, in order to prevent the thermocouples or thermal resistors from direct contact with the flame and causing damage to the wiring harness and seals, they are usually installed behind the firewall with the help of a longer pipe. The longer and thicker pipe in front of the firewall will greatly increase the actual fire surface area. Therefore, when the surface area of the flight recorder is smaller than that of the outer shell, the actual temperature rise of the medium is larger, resulting in huge errors; if a thermal insulation layer is added to prevent the error introduced by the increase in the fire surface area caused by the pipe, it is also subject to the pipe diameter and the size of the flight recorder. A considerable area of the flight recorder, which is larger than the outer shell, will be blocked by the thermal insulation material, affecting the heat flux measurement accuracy.

[0082] The present invention uses a temperature measuring tube 1 to directly measure the outlet and inlet temperatures of the flight recorder's proportional housing 4-1, avoiding measurement input errors caused by flame heating of the pipe, and at the same time avoiding damage to the sensor harness 1-7 and seals through medium protection; by designing the length of the fixed tube 4-3 so that the surface area of the tube section not covered by the thermal insulation protective layer 4-4 is equal to the surface area of the flight recorder's proportional housing 4-1 blocked by the fixed tube 4-3, the flight recorder heat flux meter's fire surface area can be approximately equivalent to the test flight recorder's fire surface area, thereby improving accuracy; through system design, the dimensions of the first tube body 1-1, the fixed tube 4-3, and the thermal insulation protective layer 4-4 are reduced to accommodate smaller flight recorders, reducing the measurement errors introduced by the above links. Through the above design, the present invention can more accurately and efficiently measure the flight recorder's heat flux, and is applicable to flight recorders with a minimum diameter or side length of 50 mm, playing an important role in the design and verification of micro and small flight recorders.

[0083] Example 2

[0084] This embodiment provides a working method of a flight recorder heat flux meter, which is applied to the flight recorder heat flux meter described in the first embodiment, and includes:

[0085] The turbine flowmeter in the flow metering tube measures the flow value of the medium and uploads it to the processor;

[0086] The temperature sensor in the first temperature measuring tube collects the inlet temperature value of the heat flux test piece flowing into the flight recorder and uploads it to the processor;

[0087] The temperature sensor in the second temperature measuring tube collects the outlet temperature value of the heat flux test piece flowing out of the flight recorder and uploads it to the industrial computer;

[0088] The industrial computer calculates the temperature difference according to the difference between the outlet temperature value and the inlet temperature value; and calculates the heat flux of the flight recorder according to the flow value, the temperature difference, the specific heat of the medium and the surface area of the flight recorder shell.

[0089] The calculation formula for the heat flux of the flight recorder is as follows:

[0090]

[0091] Where: dT represents the temperature rise of the medium, F represents the flow rate of the medium, SH represents the specific heat of the medium, A represents the surface area of the flight recorder shell, and C represents the absorption constant.

[0092] Example 3

[0093] This embodiment provides a flight recorder, including a memory and the flight recorder heat flux meter according to embodiment 1 connected to the memory.

[0094] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A flight recorder heat flux meter, characterized in that: include: A first temperature metering tube, a second temperature metering tube, a flow metering tube, an adjustable spacing pipe fixture, a flight recorder heat flux test piece, and a medium discharge pipe, One end of the flow metering tube is used to input the medium, the other end of the flow metering tube is connected to one end of the first temperature metering tube via an adjustable-space pipe fixture, the other end of the first temperature metering tube is connected to a port of the flight recorder heat flux test piece, the other port of the flight recorder heat flux test piece is connected to one end of the second temperature metering tube, the other end of the second temperature metering tube is connected to one end of the medium discharge pipe via the adjustable-space pipe fixture, the other end of the medium discharge pipe is used to discharge the medium; The first temperature measuring tube and the second temperature measuring tube are both provided with temperature sensors for detecting the temperature of the heat flux flowing into the flight recorder test piece and the temperature of the heat flux flowing out of the flight recorder test piece; A turbine flowmeter is provided in the flow metering tube to detect the flow of the medium.

2. The flight recorder heat flux meter according to claim 1, characterized in that: The first temperature measuring tube and the second temperature measuring tube have the same structure.

3. The flight recorder heat flux meter according to claim 2, characterized in that: The first temperature measuring tube further comprises: two sections of first tube body, inner protective tube, support frame, first quick pipe joint, tee, sensor harness, outlet pipe joint and first quick pipe joint seat; The inner protective tube is fixed to the central axis of the first tube body through a support frame. The end of the inner protective tube close to the flight recorder heat flux test piece is used to fix the temperature sensor. The temperature sensor is connected to the sensor wiring harness, and the sensor wiring harness is placed in the inner protective tube; the end of the inner protective tube close to the adjustable spacing pipeline fixture is provided with a boss for cooperating with the support frame to limit the position; one end of the first quick pipe joint is connected to the first tube body, and the other end of the first quick pipe joint is connected to the flight recorder heat flux test piece; the two ends of the tee are used to connect the two sections of the first tube body, and the third end is connected to the outlet pipe joint. The sensor wiring harness passes through the inner protective tube and the outlet pipe joint; the first quick pipe joint seat is used to connect the first tube body and the flow metering tube.

4. The flight recorder heat flux meter according to claim 3, characterized in that: The boss is provided with a hole for embedding the inner protective tube section of the outlet pipe joint to form a right-angle bend and limit the position.

5. The flight recorder heat flux meter according to claim 2, characterized in that: The flow metering tube further comprises: a second tube body, a second quick pipe joint, a first reducing tube joint, and a third tube body; the second tube body is used to fix the turbine flowmeter, the first reducing tube joint is used to connect the second tube body and the third tube body, and the second quick pipe joint is used to connect the third tube body and the temperature metering tube; or, The diameter of the second tube is greater than the diameter of the third tube.

6. The flight recorder heat flux meter according to claim 1, characterized in that: The adjustable spacing pipe holder includes a first fixing clip, a second fixing clip, and a slide groove. The first fixing clip and the second fixing clip have the same structure and both slide on the slide groove. By adjusting the distance between the first fixing clip and the second fixing clip, the pipe holder can accommodate flight recorder heat flux test pieces of different dimensions. or, The first tube body passes through the first fixing clamp, and the first fixing clamp is used for limiting and fixing the temperature measuring tube.

7. The flight recorder heat flux meter according to claim 1, characterized in that: The flight recorder heat flux test piece includes: a flight recorder proportional housing, a medium baffle, a fixing pipe and a second quick pipe joint seat; A medium baffle is provided in the flight recorder proportional housing to divide the space inside the flight recorder proportional housing into two parts, so as to isolate the inlet for medium flowing into the flight recorder proportional housing and the outlet for medium flowing out of the flight recorder proportional housing; The fixed tube is connected to the second quick tube connector seat, and the flight recorder housing is fixed to the fixed tube through the second quick tube connector seat; the second quick tube connector seat is used to connect the fixed tube and the temperature measuring tube; or, A heat-insulating protective layer is provided on the outer peripheral surface of the fixed pipe, which is used for heat insulation of the fixed pipe.

8. The flight recorder heat flux meter according to claim 1, characterized in that: The medium discharge pipe includes: a third quick pipe joint, a fourth pipe body, a second reducer pipe joint and a 90° elbow. One end of the third quick pipe joint is connected to the second temperature measuring tube, and the other end is connected to one end of the fourth pipe body. The other end of the fourth pipe body is connected to the second reducer pipe joint. The second reducer pipe joint is connected to the 90° elbow for discharging the medium.

9. A method for operating a flight recorder heat flux meter, characterized in that: The flight recorder heat flux meter according to any one of claims 1 to 8 comprises: The turbine flowmeter in the flow metering tube measures the flow value of the medium and uploads it to the processor; The temperature sensor in the first temperature measuring tube collects the inlet temperature value of the heat flux test piece flowing into the flight recorder and uploads it to the processor; The temperature sensor in the second temperature measuring tube collects the outlet temperature value of the heat flux test piece flowing out of the flight recorder and uploads it to the industrial computer; The industrial computer calculates the temperature difference according to the difference between the outlet temperature value and the inlet temperature value; and calculates the heat flux of the flight recorder according to the flow value, the temperature difference, the specific heat of the medium and the surface area of the flight recorder shell.

10. A flight recorder, characterized in that: The invention comprises a memory and the flight recorder heat flux meter according to any one of claims 1 to 8 connected to the memory.

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