Thermal insulation coating failure detection system

Abstract

The invention relates to the technical field of aerospace, in particular to a heat insulation coating failure detection system. Comprising a spray gun, a heat insulation plate, a heat dissipation device, piezoelectric ceramics and a signal receiving and processing device, the heat insulation plate is vertically arranged on the surface, plated with a heat insulation coating, of the to-be-detected plate body and divides the to-be-detected plate body into a first part with a large area and a second part with a small area, the spray gun is used for spraying flames to the first part, the heat dissipation device comprises a heat dissipation bottom plate, and the heat dissipation bottom plate is fixedly arranged on the edge, away from the heat insulation plate, of the second part. The heat dissipation bottom plate is provided with a groove, the piezoelectric ceramic is fixedly arranged at the bottom of the groove, the piezoelectric ceramic is connected with the heat insulation coating through the heat dissipation bottom plate so as to receive sound signals generated by internal damage of the heat insulation coating, and the signal receiving and processing device is electrically connected with the piezoelectric ceramic and used for receiving and processing electric signals generated by the piezoelectric ceramic. The embodiment of the invention provides a thermal insulation coating failure detection system which can detect the failure process of a 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] The working environment of the aircraft engine is in a high temperature environment. In order to protect the materials of the engine, a thermal insulation coating needs to be plated on the materials. However, the thermal insulation coating is prone to damage in a high temperature working environment, which in turn endangers the thermal insulation function of the coating. Therefore, failure detection of the thermal insulation coating is of great significance. 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] The embodiment of the present invention provides a thermal insulation coating failure detection system, including a spray gun, a thermal insulation plate, a heat sink, a piezoelectric ceramic, 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 the plate to be tested 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 includes a heat dissipation base plate, and the heat dissipation base plate 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 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.

[0005] In a possible design, a heat dissipation cover plate is arranged 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, and the heat dissipation cover plate and the heat dissipation base plate are connected through evaporation holes.

[0006] In a 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.

[0007] In a possible design, a collection pipeline is also included, and the spray gun is also used to output the corrosive medium; The collection pipeline runs through the heat insulation board and the heat dissipation bottom plate, one end of the collection pipeline passes through the heat insulation board and is located above the first part, and the other end of the collection pipeline is connected to a gas concentration analysis device for detecting the concentration of the corrosive medium.

[0008] In a possible design, the material of the portion of the collection pipe close to the heat insulation board is high-temperature ceramic, and the material of the portion of the collection pipe away from the heat insulation board is high-temperature metal.

[0009] 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.

[0010] In a possible design, the piezoelectric ceramic is fixed on the heat dissipation base plate via at least one connecting column.

[0011] 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.

[0012] In a possible design, the flame sprayed by the spray gun is an oxypropane flame.

[0013] In one possible design, the signal receiving and processing device includes a signal amplifier, a filter, and a signal processor.

[0014] Compared with the prior art, the present invention has at least the following beneficial effects: In this embodiment, the heat insulation board separates the plate body 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 to simulate 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 ceramics used to collect the sound 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 ceramics does not exceed 200°C, the piezoelectric ceramics cannot be directly placed on the thermal insulation coating. If other high-temperature resistant waveguide devices are used to guide the sound wave signal to a lower temperature area, and then the piezoelectric ceramics are connected to the waveguide device in the lower temperature area, the waveguide device has a longer waveguide path and more components, which easily causes the sound wave to be damaged to a certain extent, resulting in the distortion of the collected sound wave. Therefore, the present application directly places the piezoelectric ceramics on the thermal insulation coating. In order to avoid the high temperature problem, the heat insulation board is used to separate the second part where the piezoelectric ceramics are placed from the first part heated by the spray gun, which largely prevents the heat from being transferred from the upper part of the thermal insulation coating to the piezoelectric ceramics. Furthermore, a small part of the high temperature will still be transferred to the second part through the thermal insulation coating. Although the transferred heat is much less than the heat output by the spray gun, the temperature output by the spray gun is extremely high, and a small part of the heat may still damage the piezoelectric ceramic. Therefore, a heat dissipation base plate is set on the second part, and the piezoelectric ceramic is set in the groove of the heat dissipation base plate. After the piezoelectric ceramic collects the sound wave signal, it is transmitted to the signal receiving and processing device in the form of current for analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 creative work.

[0016] Figure 1 It is a structural schematic diagram of a thermal insulation coating failure detection system provided by an embodiment of the present invention.

[0017] In the figure: 100-plate to be tested; 1- Spray gun; 2- Insulation board; 3- heat dissipation base plate; 4- Heat dissipation cover; 5- groove; 6- piezoelectric ceramics; 7-evaporation hole; 8- Exhaust channel; 9-liquid inlet pipe; 10- Fluid replenishment device; 11- first fan blade; 12- second fan blade; 13- Collection pipeline; 14-connecting column; 15- Gas analysis chamber; 16-exhaust plate; 17- Collection port; 18- first exhaust port; 19- second exhaust port; 20-Gas concentration analysis device. DETAILED DESCRIPTION

[0018] 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, rather than all the embodiments. Based on the embodiments in 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.

[0019] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance; unless otherwise specified or explained, the term "multiple" refers to two or more; the terms "connected" and "fixed" should be understood in a broad sense, for example, "connected" can be a fixed connection, a detachable connection, an integral connection, or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0020] In the description of this specification, it should be understood that the directional words such as "upper" and "lower" described in the embodiments of the present invention are described at the angles shown in the drawings and should not be understood as limiting the embodiments of the present invention. In addition, in the context, it should also be understood that when it is mentioned that an element is connected to another element "upper" or "lower", it can not only be directly connected to another element "upper" or "lower", but also indirectly connected to another element "upper" or "lower" through an intermediate element.

[0021] Please refer to Figure 1 , an embodiment of the present invention provides a thermal insulation coating failure detection system, including a spray gun 1, a thermal insulation plate 2, a heat dissipation device, a piezoelectric ceramic 6 and a signal receiving and processing device; 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, and the plate body 100 to be tested is divided 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, and the heat dissipation base plate 3 is fixedly arranged at 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 heat insulation coating. The signal receiving and processing device is electrically connected to the piezoelectric ceramic 6, and is used to receive and process the electrical signal generated by the piezoelectric ceramic 6.

[0022] In this embodiment, the heat insulation board 2 separates the plate body 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 to simulate 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 sound 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 6 does not exceed 200°C, the piezoelectric ceramic 6 cannot be directly placed on the thermal insulation coating. If other high-temperature resistant waveguide devices are used to guide the sound 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 longer waveguide path and more components, which easily causes the sound wave to be damaged to a certain extent, resulting in the distortion of the collected sound 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 heat insulation board 2 is used to separate the second part where the piezoelectric ceramic 6 is placed and the first part heated by the spray gun 1, which largely prevents the heat from being transferred from the upper part of the thermal insulation coating to the piezoelectric ceramic 6. Furthermore, a small part of the high temperature will still be transferred to the second part through the thermal insulation coating. Although the transferred heat is much less than the heat output by the spray gun 1, the temperature output by the spray gun 1 is extremely high, and a small part of the heat may still damage the piezoelectric ceramic 6. Therefore, a heat dissipation base plate 3 is provided on the second part, and the piezoelectric ceramic 6 is provided in the groove 5 of the heat dissipation base plate 3. After the piezoelectric ceramic 6 collects the sound wave signal, it is transmitted to the signal receiving and processing device in the form of current for analysis.

[0023] In some embodiments of the present invention, a heat dissipation cover plate 4 is arranged on the top of the heat dissipation base plate 3, and 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, and the heat dissipation cover plate 4 and the heat dissipation base plate 3 are connected through an evaporation hole 7.

[0024] In this embodiment, the heat dissipation base plate 3 is filled with water, and its bottom is directly connected to the heat source insulation coating. After the heat is conducted to the water in the heat dissipation base plate 3, the water is heated and vaporized, and the vaporization absorbs a large amount of heat, so that the piezoelectric ceramics 6 in the groove 5 are at a suitable temperature. The heat dissipation cover plate 4 on the top of the heat dissipation base plate 3 receives the high-temperature steam that is vaporized and expanded, and dissipates it, achieving the effect of efficient heat dissipation.

[0025] 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 a 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.

[0026] In this embodiment, the vaporized gas is discharged through the exhaust channel 8, and the gas expands rapidly at high temperature, forming 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 passing through the first fan blade 11, it drives it to rotate. The first fan blade 11 is axially connected to the second fan blade 12, and then 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 realizing continuous and efficient heat dissipation.

[0027] It should be noted that the first blade 11 and the second blade 12 on different axes can be linked together by means of a gear set.

[0028] 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; The collection pipe 13 passes through the insulation board 2 and the heat dissipation base plate 3, one end of the collection pipe 13 passes through the insulation board 2 and is located above the first part, and 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.

[0029] In the real working environment of the aircraft, in addition to facing high temperatures, it will also be corroded by volcanic ash, PM2.5 and gaseous corrosive media. The superposition 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 high-temperature flames, the spray gun 1 also sprays a corrosive medium with 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 be detected 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.

[0030] The gas concentration analysis device 20 can be arranged in the gas analysis chamber 15, and the gas analysis chamber 15 includes a collection port 17 connected to the collection pipeline 13, a first exhaust port 18 and a second exhaust port 19. The gas analysis chamber 15 includes a reciprocating exhaust plate 16, and the exhaust plate 16 divides the gas analysis chamber 15 into two parts. The collection port 17 and the first exhaust port 18 are respectively located on two opposite chamber walls of the gas analysis chamber 15, and the second exhaust port 19 and the collection port 17 are located on the chamber wall on the same side. When collecting gas, the exhaust plate 16 moves from the chamber wall on the side where the collection port 17 is set to the side of the first exhaust port 18, so that the gas to be detected fills the gas analysis chamber 15 for concentration detection. After the detection 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 set, and the internal gas is discharged from the second exhaust port 19, and then the second exhaust port 19 is closed, and the collection port 17 is opened to continue collecting gas.

[0031] In some embodiments of the present invention, the material of the portion of the collection pipe 13 close to the insulation board 2 is high-temperature ceramic, and the material of the portion of the collection pipe 13 away from the insulation board 2 is high-temperature metal.

[0032] 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.

[0033] 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.

[0034] In this embodiment, the vacuum can provide heat insulation and create a suitable working environment for the piezoelectric ceramic 6 .

[0035] 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.

[0036] 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 .

[0037] In this embodiment, the contact area between the piezoelectric ceramic 6 and the heat dissipation base plate 3 is reduced by the connection column 14, which is helpful to reduce heat transfer.

[0038] 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 8-15 cm.

[0039] In this embodiment, the distance of 8-15 cm can dissipate most of the heat in time, thereby protecting the piezoelectric ceramic 6 in the rear position.

[0040] In some embodiments of the present invention, the flame sprayed by the spray gun 1 is an oxypropane flame.

[0041] The signal receiving and processing device comprises a signal amplifier, a filter and a signal processor.

[0042] 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 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 sink, a piezoelectric ceramic 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 the plate to be tested 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 includes a heat dissipation base plate, and the heat dissipation base plate 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 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.

2. The system according to claim 1, characterized in that A heat dissipation cover plate is arranged 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.

3. The system according to claim 2, characterized in that 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 faces 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 faces the heat dissipation base plate, and the rotating shafts of the first fan blade and the second fan blade are fixedly connected.

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

5. The system according to claim 4, characterized in that The material of the portion of the collection pipeline close to the heat insulation board is high-temperature ceramic, and the material of the portion of the collection pipeline far from the heat insulation board is high-temperature metal.

6. The system according to claim 1, characterized in that A sealing plate is arranged on the upper part of the groove to make the groove a sealed space, and a vacuum channel is arranged on the inner wall of the groove to make the groove a vacuum environment.

7. The system according to claim 1, characterized in that The piezoelectric ceramic is fixed on the heat dissipation base plate through at least one connecting column.

8. The system according to claim 1, characterized in that The distance between the end of the heat dissipation base plate close to the heat insulation plate and the groove is 8-15 cm.

9. The system according to claim 1, characterized in that The flame sprayed by the spray gun is an oxygen-propane flame.

10. The system according to claim 1, characterized in that The signal receiving and processing device comprises a signal amplifier, a filter and a signal processor.

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