A thermal insulation coating failure detection system

Abstract

The present invention relates to the field of aerospace technology, and in particular to a thermal insulation coating failure detection system. It comprises a spray gun, a thermal insulation plate, a heat dissipation device, a piezoelectric ceramic, and a signal receiving and processing device; the thermal insulation plate is vertically arranged on the surface of the plate to be detected that is coated with the thermal insulation coating, and the plate to be detected is divided into a first part with a larger area and a second part with a smaller area. The spray gun is used to spray flames to the first part. The heat dissipation device comprises a heat dissipation base plate, which is fixedly arranged on the edge of the second part away from the thermal insulation plate. The heat dissipation base plate is provided with a groove, and the piezoelectric ceramic is fixedly arranged at the bottom of the groove, so that the piezoelectric ceramic is connected to the thermal insulation coating through the heat dissipation base plate to receive the sound signal generated by the internal damage of the thermal insulation coating. The signal receiving and processing device is electrically connected to the piezoelectric ceramic, and is used to receive and process the electrical signal generated by the piezoelectric ceramic. An embodiment of the present invention provides a thermal insulation coating failure detection system that can detect the failure process of the thermal insulation coating.

Description

Technical Field

[0001] The present invention relates to the field of aerospace technology, and in particular to a thermal insulation coating failure detection system. Background Art

[0002] Aircraft engines operate in high-temperature environments. To protect the engine materials, they require thermal insulation coatings. However, thermal insulation coatings are prone to damage in high-temperature environments, compromising their thermal insulation properties. Therefore, failure detection of thermal insulation coatings is crucial. Summary of the Invention

[0003] An embodiment of the present invention provides a thermal insulation coating failure detection system capable of detecting the failure process of the thermal insulation coating.

[0004] An embodiment of the present invention provides a thermal insulation coating failure detection system, including a spray gun, a thermal insulation plate, a heat sink, piezoelectric ceramics, and a signal receiving and processing device;

[0005] The heat insulation plate is vertically arranged on the surface of the plate to be tested that is coated with the heat insulation coating, and divides the plate to be tested into a first part with a larger area and a second part with a smaller area. The spray gun is used to spray flames onto the first part. The heat dissipation device includes a heat dissipation base plate, which is fixedly arranged on the edge of the second part away from the heat insulation plate. The heat dissipation base plate is provided with a groove. The piezoelectric ceramic is fixedly arranged at the bottom of the groove so that the piezoelectric ceramic is connected to the heat insulation coating through the heat dissipation base plate to receive the sound signal generated by the internal damage of the heat insulation coating. The signal receiving and processing device is electrically connected to the piezoelectric ceramic and is used to receive and process the electrical signal generated by the piezoelectric ceramic.

[0006] In one possible design, a heat dissipation cover is provided on the top of the heat dissipation base plate. The heat dissipation cover plate and the heat dissipation base plate are both hollow shell structures. The heat dissipation base plate is filled with water. The heat dissipation cover plate and the heat dissipation base plate are connected through evaporation holes.

[0007] In one possible design, the heat dissipation cover plate is provided with an exhaust channel, the heat dissipation base plate is connected to the liquid replenishing device through a liquid inlet pipe, the exhaust channel is provided with a first fan blade, the first fan blade is facing the gas source of the exhaust channel, the liquid inlet pipe or the liquid replenishing device is provided with a second fan blade, the second fan blade is facing the heat dissipation base plate, and the rotating shafts of the first fan blade and the second fan are fixedly connected.

[0008] In a possible design, a collection pipe is also included, and the spray gun is also used to output the corrosive medium;

[0009] The collection pipe runs through the heat insulation board and the heat dissipation base plate, one end of the collection pipe passes through the heat insulation board and is located above the first part, and the other end of the collection pipe is connected to a gas concentration analysis device for detecting the concentration of the corrosive medium.

[0010] In a possible design, the material of the portion of the collection pipe close to the heat insulation plate is high-temperature ceramic, and the material of the portion of the collection pipe away from the heat insulation plate is high-temperature metal.

[0011] In a possible design, a sealing plate is provided on the upper portion of the groove to make the groove a sealed space, and a vacuum channel is provided on the inner wall of the groove, and the vacuum channel is used to make the groove a vacuum environment.

[0012] In a possible design, the piezoelectric ceramic is fixed to the heat dissipation base plate via at least one connecting column.

[0013] In a possible design, the distance between the end of the heat dissipation base plate close to the heat insulation plate and the groove is 8 to 15 cm.

[0014] In a possible design, the flame sprayed by the spray gun is an oxypropane flame.

[0015] In one possible design, the signal receiving and processing device includes a signal amplifier, a filter, and a signal processor.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects:

[0017] In this embodiment, the heat shield separates the plate to be tested into a first part and a second part. The first part with a larger area is used to receive the flame sprayed by the spray gun, simulating the high-temperature working environment of the engine to test the service life of the thermal insulation coating; the second part with a smaller area is used to place the piezoelectric ceramic used to collect the acoustic wave signal generated by the damage of the thermal insulation coating. Since the test environment temperature is high and the operating temperature of the piezoelectric ceramic does not exceed 200°C, it is impossible to directly place the piezoelectric ceramic on the thermal insulation coating. If other high-temperature resistant waveguide devices are used to guide the acoustic wave signal to a lower temperature area, and then the piezoelectric ceramic is connected to the waveguide device in the lower temperature area, the waveguide device has a long waveguide path and many components, which can easily cause a certain degree of damage to the acoustic wave, resulting in distortion of the collected acoustic wave. Therefore, the present application directly places the piezoelectric ceramic on the thermal insulation coating. In order to avoid the high temperature problem, the heat shield is used to separate the second part where the piezoelectric ceramic is placed from the first part heated by the spray gun, which greatly prevents heat from being transferred from the upper part of the thermal insulation coating to the piezoelectric ceramic. Furthermore, a small amount of high temperature will still be transferred to the second part through the thermal insulation coating. Although the amount of heat transferred is far less than the heat output by the spray gun, the extremely high temperature output by the spray gun can still damage the piezoelectric ceramic. Therefore, a heat sink is installed on the second part, and the piezoelectric ceramic is placed in the groove of the heat sink. After the piezoelectric ceramic collects the acoustic wave signal, it is transmitted as an electric current to the signal receiving and processing device for analysis. 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 briefly introduces 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 work.

[0019] Figure 1 It is a structural schematic diagram of a thermal insulation coating failure detection system provided by an embodiment of the present invention.

[0020] In the picture:

[0021] 100-plate to be tested;

[0022] 1-Spray gun;

[0023] 2- thermal insulation board;

[0024] 3- heat dissipation base plate;

[0025] 4-heat dissipation cover;

[0026] 5-groove;

[0027] 6- piezoelectric ceramics;

[0028] 7-evaporation hole;

[0029] 8-Exhaust channel;

[0030] 9-liquid inlet pipe;

[0031] 10- Fluid refill device;

[0032] 11-first fan blade;

[0033] 12- second fan blade;

[0034] 13- Collection pipeline;

[0035] 14-connecting column;

[0036] 15-Gas analysis chamber;

[0037] 16-exhaust plate;

[0038] 17-collection port;

[0039] 18-first exhaust port;

[0040] 19- second exhaust port;

[0041] 20-Gas concentration analysis device. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0043] In the description of the embodiments of the present invention, unless otherwise expressly specified or limited, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance; unless otherwise specified or explained, the term "plurality" refers to two or more; the terms "connected" and "fixed" should be understood in a broad sense. For example, "connected" can mean a fixed connection, a detachable connection, an integral connection, or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] In the description of this specification, it should be understood that the directional terms such as "upper" and "lower" described in the embodiments of the present invention are described from the perspectives shown in the accompanying drawings and should not be understood as limiting the embodiments of the present invention. In addition, in the context, it should be understood that when it is mentioned that an element is connected "upper" or "lower" of another element, it can not only be directly connected "upper" or "lower" of the other element, but also indirectly connected "upper" or "lower" of the other element through an intermediate element.

[0045] Please refer to Figure 1 , an embodiment of the present invention provides a thermal insulation coating failure detection system, comprising a spray gun 1, a thermal insulation plate 2, a heat dissipation device, a piezoelectric ceramic 6 and a signal receiving and processing device;

[0046] The heat insulation plate 2 is vertically arranged on the surface of the plate body 100 to be tested that is coated with the heat insulation coating, dividing the plate body 100 to be tested into a first part with a larger area and a second part with a smaller area. The spray gun 1 is used to spray flames to the first part. The heat dissipation device includes a heat dissipation base plate 3, which is fixedly arranged on the edge of the second part away from the heat insulation plate 2. The heat dissipation base plate 3 is provided with a groove 5. The piezoelectric ceramic 6 is fixedly arranged at the bottom of the groove 5, so that the piezoelectric ceramic 6 is connected to the heat insulation coating through the heat dissipation base plate 3 to receive the sound signal generated by the internal damage of the thermal insulation coating. The signal receiving and processing device is electrically connected to the piezoelectric ceramic 6 for receiving and processing the electrical signal generated by the piezoelectric ceramic 6.

[0047] In this embodiment, the thermal insulation board 2 separates the plate 100 to be tested into a first part and a second part. The first part with a larger area is used to receive the flame sprayed by the spray gun 1, simulating the high temperature working environment of the engine to test the service life of the thermal insulation coating; the second part with a smaller area is used to place the piezoelectric ceramic 6 used to collect the acoustic wave signal generated by the damage of the thermal insulation coating. Because the test environment temperature is high and the operating temperature of the piezoelectric ceramic 6 does not exceed 200°C, it is impossible to place the piezoelectric ceramic 6 directly on the thermal insulation coating. If other high-temperature resistant waveguide devices are used to guide the acoustic wave signal to a lower temperature area, and then the piezoelectric ceramic 6 is connected to the waveguide device in the lower temperature area, the waveguide device has a long waveguide path and many components, which can easily cause a certain degree of damage to the acoustic wave, resulting in distortion of the collected acoustic wave. Therefore, the present application directly places the piezoelectric ceramic 6 on the thermal insulation coating. In order to avoid the high temperature problem, the thermal insulation board 2 is used to separate the second part where the piezoelectric ceramic 6 is placed from the first part heated by the spray gun 1, which greatly prevents heat from being transferred from the upper part of the thermal insulation coating to the piezoelectric ceramic 6. Furthermore, a small amount of high temperature will still be transferred to the second section through the thermal insulation coating. Although the amount of heat transferred is far less than the heat output by the spray gun 1, the extremely high temperature output by the spray gun 1 still poses a risk of damaging the piezoelectric ceramic 6. Therefore, a heat sink 3 is provided on the second section, and the piezoelectric ceramic 6 is placed in the groove 5 of the heat sink 3. After the piezoelectric ceramic 6 collects the acoustic wave signal, it transmits it as an electric current to the signal receiving and processing device for analysis.

[0048] In some embodiments of the present invention, a heat dissipation cover plate 4 is provided on the top of the heat dissipation base plate 3. The heat dissipation cover plate 4 and the heat dissipation base plate 3 are both hollow shell structures. The heat dissipation base plate 3 is filled with water. The heat dissipation cover plate 4 and the heat dissipation base plate 3 are connected through an evaporation hole 7.

[0049] In this embodiment, heat dissipation baseplate 3 is filled with water, and its bottom is directly connected to the heat source insulation coating. Heat is conducted to the water within baseplate 3, causing it to heat up and vaporize. This vaporization absorbs a large amount of heat, maintaining the piezoelectric ceramic 6 within groove 5 at a suitable temperature. Heat dissipation cover plate 4 on top of baseplate 3 receives the high-temperature vapor that expands during vaporization and dissipates it, achieving efficient heat dissipation.

[0050] In some embodiments of the present invention, the heat dissipation cover plate 4 is provided with an exhaust channel 8, the heat dissipation base plate 3 is connected to the liquid replenishing device 10 through the liquid inlet pipe 9, the exhaust channel 8 is provided with a first fan blade 11, the first fan blade 11 is facing the gas source of the exhaust channel 8, the liquid inlet pipe 9 or the liquid replenishing device 10 is provided with a second fan blade 12, the second fan blade 12 is facing the heat dissipation base plate 3, and the rotating shafts of the first fan blade 11 and the second fan blade 12 are fixedly connected.

[0051] In this embodiment, the vaporized gas is discharged through the exhaust channel 8. The gas expands rapidly at high temperature and forms a higher air pressure under the restriction of the exhaust channel 8. The high pressure provides a stronger power for the gas circulation, and then when it passes through the first fan blade 11, it drives it to rotate. The first fan blade 11 and the second fan blade 12 are axially connected, which drives the second fan blade 12 to rotate. The second fan blade 12 replenishes the low-temperature water in the liquid replenishing device 10 to the heat dissipation base plate 3 through the liquid inlet pipe 9, thereby achieving continuous and efficient heat dissipation.

[0052] It should be noted that the first fan blade 11 and the second fan blade 12 on different axes can be linked together by means of a gear set.

[0053] In some embodiments of the present invention, the system further comprises a collection pipeline 13, and the spray gun 1 is also used to output the corrosive medium;

[0054] The collection pipe 13 passes through the heat insulation board 2 and the heat dissipation base plate 3. One end of the collection pipe 13 passes through the heat insulation board 2 and is located above the first part. The other end of the collection pipe 13 is connected to a gas concentration analysis device 20 for detecting the concentration of the corrosive medium.

[0055] In the real working environment of an aircraft, in addition to being exposed to high temperatures, it will also be corroded by volcanic ash, PM2.5 and gaseous corrosive media. The combination of corrosive media and high temperature is an important factor causing the failure of the thermal insulation coating. Therefore, in order to more realistically reflect the service life of the thermal insulation coating, in addition to creating a high-temperature environment, a corrosive medium environment must also be created. Therefore, in addition to spraying a high-temperature flame, the spray gun 1 also sprays a corrosive medium with an adjustable concentration. However, the concentration of the corrosive medium in the spray gun 1 is different from the concentration on the surface of the thermal insulation coating. Therefore, the concentration of the corrosive medium must be collected. Specifically, the gas above the thermal insulation coating is collected through the collection pipe 13. Similarly, the gas detection device cannot perform detection at high temperatures. Therefore, the collection pipe 13 passes through the heat dissipation base plate 3. After the collected gas passes through the heat dissipation base plate 3, the heat is dissipated through the heat dissipation base plate 3, and the temperature drops rapidly. Finally, it is received and tested by the gas concentration analysis device 20 to obtain the concentration of the corrosive medium.

[0056] The gas concentration analysis device 20 can be installed in the gas analysis chamber 15. The gas analysis chamber 15 includes a collection port 17 connected to the collection pipe 13, a first exhaust port 18, and a second exhaust port 19. The gas analysis chamber 15 includes a reciprocating exhaust plate 16, which divides the gas analysis chamber 15 into two parts. The collection port 17 and the first exhaust port 18 are located on opposite sides of the chamber wall, while the second exhaust port 19 is located on the same side of the chamber wall as the collection port 17. During gas collection, the exhaust plate 16 moves from the chamber wall where the collection port 17 is located to the side of the first exhaust port 18, allowing the gas to fill the gas analysis chamber 15 for concentration testing. After the test is completed, the collection port 17 is closed, the first exhaust port 18 and the second exhaust port 19 are opened, and the exhaust plate 16 is controlled to move to the chamber wall where the collection port 17 is located, allowing the internal gas to be discharged through the second exhaust port 19. The second exhaust port 19 is then closed, and the collection port 17 is opened to continue gas collection.

[0057] In some embodiments of the present invention, the portion of the collection pipe 13 close to the insulation board 2 is made of high-temperature ceramics, and the portion of the collection pipe 13 away from the insulation board 2 is made of high-temperature metals.

[0058] In this embodiment, the high-temperature ceramic is resistant to high temperatures and is close to the heat source, and the high-temperature metal has good thermal conductivity, which facilitates the heat dissipation of the collected gas.

[0059] In some embodiments of the present invention, a sealing plate is provided on the upper portion of the groove 5 to make the groove 5 a sealed space, and a vacuum channel is provided on the inner wall of the groove 5 to make the groove 5 a vacuum environment.

[0060] In this embodiment, vacuum can provide heat insulation and create a suitable working environment for the piezoelectric ceramic 6 .

[0061] The inner wall of the groove 5 is provided with a line pipe for connecting the lines, and the port of the line pipe is provided with a sealing ring to keep the groove 5 sealed.

[0062] In some embodiments of the present invention, the piezoelectric ceramic 6 is fixed on the heat dissipation base plate 3 via at least one connecting column 14 .

[0063] In this embodiment, the contact area between the piezoelectric ceramic 6 and the heat dissipation base plate 3 is reduced by the connecting pillars 14, which is beneficial to reducing heat transfer.

[0064] In some embodiments of the present invention, the distance between the end of the heat dissipation base plate 3 close to the heat insulation plate 2 and the groove 5 is 8 to 15 cm.

[0065] In this embodiment, a distance of 8 to 15 cm can dissipate most of the heat in time, thereby protecting the piezoelectric ceramic 6 in the rear position.

[0066] In some embodiments of the present invention, the flame sprayed by the spray gun 1 is an oxypropane flame.

[0067] The signal receiving and processing device includes a signal amplifier, a filter and a signal processor.

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A thermal insulation coating failure detection system, characterized in that: It includes a spray gun, a heat shield, a heat dissipation device, piezoelectric ceramics and a signal receiving and processing device; The heat insulation plate is vertically arranged on the surface of the plate to be tested that is coated with the heat insulation coating, and divides the plate to be tested into a first part with a larger area and a second part with a smaller area. The spray gun is used to spray flames onto the first part. The heat dissipation device includes a heat dissipation base plate, which is fixedly arranged on the edge of the second part away from the heat insulation plate. The heat dissipation base plate is provided with a groove. The piezoelectric ceramic is fixedly arranged at the bottom of the groove so that the piezoelectric ceramic is connected to the heat insulation coating through the heat dissipation base plate to receive sound signals generated by internal damage of the heat insulation coating. The signal receiving and processing device is electrically connected to the piezoelectric ceramic, and is used to receive and process the electrical signal generated by the piezoelectric ceramic. A heat dissipation cover is provided on the top of the heat dissipation base plate. The heat dissipation cover and the heat dissipation base plate are both hollow shell structures. Water is contained in the heat dissipation base plate. The heat dissipation cover and the heat dissipation base plate are connected through evaporation holes. The heat dissipation cover on the top of the heat dissipation base plate is used to receive the evaporated and expanded high-temperature steam and dissipate it. The heat dissipation cover is provided with an exhaust channel, the heat dissipation base plate is connected to the liquid replenishing device through a liquid inlet pipe, the exhaust channel is provided with a first fan blade, the first fan blade is directed toward the gas source of the exhaust channel, the liquid inlet pipe or the liquid replenishing device is provided with a second fan blade, the second fan blade is directed toward the heat dissipation base plate, and the rotating shafts of the first fan blade and the second fan blade are fixedly connected; A sealing plate is provided on the upper portion of the groove to form a sealed space, and a vacuum channel is provided on the inner wall of the groove to form a vacuum environment in the groove; The piezoelectric ceramic is fixed on the heat dissipation base plate via at least one connecting column; The distance between the end of the heat dissipation base plate close to the heat insulation plate and the groove is 8 to 15 cm.

2. The system according to claim 1, wherein: It also includes a collection pipeline, and the spray gun is also used to output the corrosive medium; The collection pipe runs through the heat insulation board and the heat dissipation base plate, one end of the collection pipe passes through the heat insulation board and is located above the first part, and the other end of the collection pipe is connected to a gas concentration analysis device for detecting the concentration of the corrosive medium.

3. The system according to claim 2, characterized in that The material of the portion of the collection pipe close to the heat insulation plate is high-temperature ceramic, and the material of the portion of the collection pipe away from the heat insulation plate is high-temperature metal.

4. The system according to claim 1, wherein: The flame sprayed by the spray gun is an oxygen-propane flame.

5. The system according to claim 1, wherein: The signal receiving and processing device includes a signal amplifier, a filter and a signal processor.

Images