Foam-based thermal insulation and electrical friction materials, preparation methods, sensors and fault detection methods

Abstract

This invention discloses a foam-based thermal insulation and electromechanical material, its preparation method, a sensor, and a fault detection method, relating to the field of intelligent sensing and vibration anomaly detection technology. The preparation method includes: adding a mixture of glucose and ammonium chloride to deionized water to form a homogeneous solution; adding perlite powder to the homogeneous solution and stirring, then calcining under a nitrogen atmosphere to obtain a black foam-like solid; grinding the black foam-like solid into perlite-graphene composite particles; and mixing the perlite-graphene composite particles into PDMS prepolymer at a preset doping ratio, followed by stirring and curing to obtain the foam-based thermal insulation and electromechanical material. This invention alleviates the technical problems of instability and low accuracy of traditional sensors under high temperatures and long-term operation.

Description

Technical Field

[0001] This invention relates to the field of intelligent sensing and vibration anomaly detection technology, and in particular to a foam-based thermal insulation and electro-hydraulic material, its preparation method, sensor, and fault detection method. Background Technology

[0002] Triboelectric nanogenerators, as an emerging energy harvesting and self-driven sensing technology, have shown significant potential in the field of mechanical vibration monitoring due to their simple structure, flexible material selection, and strong environmental adaptability. However, the application of traditional triboelectric nanogenerator friction layer materials in high-temperature environments has significant limitations. For example, the extreme high temperatures (typically exceeding 100°C) generated during the operation of industrial equipment such as engines can cause thermal degradation of conventional polymer-based friction materials (such as polydimethylsiloxane (PDMS)), leading to a sharp decline in electrical output performance or even failure. Furthermore, existing triboelectric nanogenerator sensors generally suffer from insufficient sensitivity and narrow dynamic response range in high-temperature vibration detection, making it difficult to accurately capture complex vibration signal characteristics and limiting their application in high-precision scenarios such as engine and compressor fault diagnosis.

[0003] Currently, research on improving triboelectric nanogenerators for high-temperature environments mainly focuses on the development of heat-resistant materials. For example, while using ceramic fibers to reinforce the structure of triboelectric nanogenerators improves heat resistance, the excessive rigidity of the material leads to reduced vibration sensing sensitivity. Furthermore, existing engine vibration monitoring systems mostly rely on piezoelectric sensors or accelerometers. These devices require external power and have limited high-temperature resistance (e.g., piezoelectric ceramics are prone to polarization failure at 200°C), and also lack multi-fault classification capabilities based on the dynamic range of vibration signals.

[0004] In signal processing, traditional methods typically rely on thresholding to determine vibration anomalies. However, engine faults are diverse (such as bearing wear, piston imbalance, and ignition malfunctions), and a single threshold is insufficient to distinguish complex fault modes. Therefore, there is an urgent need to develop a triboelectric nanogenerator sensor with high-temperature resistance, high output stability, and intelligent fault diagnosis capabilities to achieve efficient monitoring of engine vibration. Summary of the Invention

[0005] To address the instability and low accuracy of traditional sensors under high temperatures and long-term operation, this invention provides a foam-based thermal insulation and electro-electric material, its preparation method, a sensor, and a fault detection method. The technical solution is as follows:

[0006] On one hand, a method for preparing a foam-based thermal insulation and electric friction material is provided, comprising: adding a mixture of glucose and ammonium chloride to deionized water to form a homogeneous solution; adding perlite powder to the homogeneous solution and stirring, and calcining it under a nitrogen atmosphere to obtain a black foam-like solid; grinding the black foam-like solid into perlite-graphene composite particles; mixing the perlite-graphene composite particles into PDMS prepolymer at a preset doping ratio and stirring and curing to obtain the foam-based thermal insulation and electric friction material.

[0007] Optionally, the preset doping ratio includes 2wt%-10wt%.

[0008] Optionally, calcination is carried out under a nitrogen atmosphere, including calcination at a temperature of 900℃-1350℃ for 3-5 hours under a nitrogen atmosphere.

[0009] On the other hand, a foam-based thermal insulation and electric friction material is also provided, which is made based on the preparation method of the foam-based thermal insulation and electric friction material provided in the embodiments of the present invention.

[0010] On the other hand, a high-temperature vibration sensor based on a foam-based thermally insulating triboelectric nanogenerator is also provided, including a friction layer and two electrodes, wherein the friction layer is disposed between the two electrodes, and the friction layer is made of a foam-based thermally insulating triboelectric material provided in the embodiments of the present invention.

[0011] Optionally, the thickness of the friction layer includes 1mm-3mm.

[0012] Optionally, both electrodes are copper conductive strips.

[0013] On the other hand, a fault detection method for a high-temperature vibration sensor based on a foam-based thermally insulating triboelectric nanogenerator provided in the embodiments of the present invention is also provided, comprising: acquiring vibration signal data of a vibrating body to be tested based on the high-temperature vibration sensor; determining whether the vibration signal data is within a preset vibration data range; if yes, determining that the vibrating body to be tested is in a fault-free state; if no, determining that the vibrating body to be tested is in a fault state, and determining the fault type of the vibrating body to be tested based on a preset fault database.

[0014] Optionally, the method further includes: acquiring a normal vibration dataset of the vibrating body under fault-free conditions based on the high-temperature vibration sensor; preprocessing the normal vibration dataset to obtain a preset vibration data range; acquiring a fault vibration dataset of the vibrating body under different fault conditions based on the high-temperature vibration sensor; preprocessing the fault vibration dataset to obtain a preset fault database; the preset fault database includes fault vibration data ranges corresponding to different fault types.

[0015] Optionally, determining the fault type of the vibrating machine body to be tested based on a preset fault database includes: determining the fault type corresponding to the fault vibration data range where the vibration signal data is located as the fault type of the vibrating machine body to be tested.

[0016] This invention provides a foam-based thermal insulation triboelectric material, its preparation method, a sensor, and a fault detection method. By designing a perlite-graphene composite foam-based triboelectric nanogenerator, the material's heat resistance and triboelectric properties are synergistically optimized, and the vibration response sensitivity is improved by combining a multi-level porous structure design. A low-cost and simple preparation method is used to synthesize the foam-based thermal insulation composite material, which is then designed as a high-temperature vibration sensor to detect abnormal machine vibrations. This overcomes the instability and accuracy problems of traditional sensors under high temperatures and long-term operation, filling the gap in the field of high-temperature intelligent engine and air conditioning compressor abnormal vibration sensing. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart of a method for preparing a foam-based thermal insulation and electro-hydraulic material according to an embodiment of the present invention;

[0019] Figure 2 The image shows the XRD pattern of perlite-graphene composite particles obtained according to the preparation method provided in this embodiment.

[0020] Figure 3 The image shows the Raman diagram of perlite-graphene composite particles obtained according to the preparation method provided in this embodiment.

[0021] Figure 4 This is a TEM image of perlite-graphene composite particles obtained according to the preparation method provided in this embodiment;

[0022] Figure 5 This is a thermal conductivity and thermogravimetric analysis diagram of a foam-based thermal insulation and electrostatic material according to an embodiment of the present invention;

[0023] Figure 6 This is a thermal insulation test diagram of a foam-based thermal insulation and electro-hydraulic material according to an embodiment of the present invention;

[0024] Figure 7This is a schematic diagram of the structure of a high-temperature vibration sensor based on a foam-based thermally insulated triboelectric nanogenerator according to an embodiment of the present invention;

[0025] Figure 8 This is a voltage, current, and stability test diagram of a high-temperature vibration sensor provided according to an embodiment of the present invention;

[0026] Figure 9 This is a test diagram of the output performance and heat resistance of a high-temperature vibration sensor under contact separation mode according to an embodiment of the present invention;

[0027] Figure 10 This is a power supply test diagram of a high-temperature vibration sensor according to an embodiment of the present invention;

[0028] Figure 11 This is a flowchart of a fault detection method based on a high-temperature vibration sensor using a foam-based thermally insulating triboelectric nanogenerator, according to an embodiment of the present invention.

[0029] Figure 12 This is an abnormal vibration detection diagram of a high-temperature vibration sensor provided according to an embodiment of the present invention;

[0030] Figure 13 This is a fault detection output signal and stability diagram of a high-temperature vibration sensor provided according to an embodiment of the present invention. Detailed Implementation

[0031] The technical solution of the present invention will now be described with reference to the accompanying drawings.

[0032] In embodiments of the present invention, words such as "exemplarily," "for example," etc., are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" in the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the word "exemplary" is intended to present the concept in a concrete manner. Furthermore, in embodiments of the present invention, the meaning expressed by "and / or" can be both, or either one.

[0033] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0034] Example 1

[0035] Figure 1 This is a flowchart illustrating a method for preparing a foam-based thermal insulation and electro-hydraulic material according to an embodiment of the present invention. Figure 1 As shown, the method specifically includes the following steps:

[0036] In step S102, a mixture of glucose and ammonium chloride is added to deionized water to form a homogeneous solution.

[0037] Step S104: Perlite powder is added to the homogeneous solution and stirred, and then calcined under a nitrogen atmosphere to obtain a black foamy solid.

[0038] Preferably, the calcination is carried out in a nitrogen atmosphere at a temperature of 900℃-1350℃ for 3-5 hours.

[0039] Step S106: Grind the black foamy solid into perlite-graphene composite particles.

[0040] Step S108: Perlite-graphene composite particles are mixed into PDMS prepolymer at a preset doping ratio and stirred and cured to obtain foam-based thermal insulation and electrostatic material.

[0041] In this embodiment of the invention, PMDS is polydimethylsiloxane, which is a polymer material.

[0042] Optionally, the preset doping ratio includes 2wt%-10wt%, and preferably, the preset doping ratio is 4wt%-8wt%.

[0043] Several optional embodiments of the preparation method of a foam-based thermal insulation and electrostatic material provided in this invention are as follows:

[0044] Implementation method 1:

[0045] Glucose and ammonium chloride were mixed in a 1:1 weight ratio and deionized water was added to form a homogeneous solution. Then, 2g of perlite powder was added to the solution and stirred for 10-30 minutes. Subsequently, the mixture was calcined at 900-1350℃ (heating rate of 1-5℃ / min) for 3-5 hours under a nitrogen atmosphere. Finally, the black foamy solid was ground into perlite-graphene composite particles (Ex-Pe@G particles).

[0046] The doping ratio of Ex-Pe@G particles is 2-10 wt%, and the mass ratio of PDMS prepolymer to curing agent is 10:1; the mixing and stirring speed is set to 200-800 rpm / min, the stirring time is 5-30 minutes, and the curing conditions are heating at 100-150℃ for 30-50 minutes, finally obtaining a foam-based thermal insulation and electrostatic material.

[0047] The preferred doping ratio of Ex-Pe@G powder is 4-8 wt%, and the stirring speed is 400-800 rpm, so as to form a multi-level porous composite foam electrostatic material with a pore size distribution of 10-200 μm.

[0048] Implementation Method 2:

[0049] Glucose and ammonium chloride were mixed in a 1:1 weight ratio and deionized water was added to form a homogeneous solution. Then, 2g of perlite powder was added to the solution and stirred for 10 minutes. Subsequently, the solution was calcined at 1200℃ (heating rate of 3℃ / min) for 3 hours under a nitrogen atmosphere. Finally, the black foamy solid was ground into Ex-Pe@G particles.

[0050] The doping ratio of Ex-Pe@G particles was 4wt%, and the mass ratio of PDMS prepolymer to curing agent was 10:1; the mixing speed was set to 400rpm / min, the mixing time was 10 minutes, and the curing conditions were heating at 120℃ for 50 minutes.

[0051] Figure 2 The image shows the XRD pattern of the perlite-graphene composite particles obtained according to the preparation method provided in this embodiment. Figure 3 The image shows the Raman diagram of the perlite-graphene composite particles obtained according to the preparation method provided in this embodiment. Figure 4 This is a TEM image of perlite-graphene composite particles obtained according to the preparation method provided in this embodiment.

[0052] Implementation Method 3:

[0053] Glucose and ammonium chloride were mixed in a 1:1 weight ratio and deionized water was added to form a homogeneous solution. Then, 2g of perlite powder was added to the solution and stirred for 30 minutes. Subsequently, the solution was calcined at 1350℃ (heating rate of 5℃ / min) for 5 hours under a nitrogen atmosphere. Finally, the black foamy solid was ground into Ex-Pe@G particles.

[0054] The doping ratio of Ex-Pe@G powder was 8wt%, and the mass ratio of PDMS prepolymer to curing agent was 10:1; the mixing speed was set to 800rpm / min, the mixing time was 20 minutes, and the curing conditions were heating at 110℃ for 40 minutes.

[0055] Example 2

[0056] This invention also provides a foam-based thermal insulation and electro-hydraulic material, which is prepared based on the method for preparing the foam-based thermal insulation and electro-hydraulic material provided in this invention.

[0057] Figure 5 This is a thermal conductivity and thermogravimetric analysis diagram of a foam-based thermal insulation and electrostatic material according to an embodiment of the present invention. Figure 6 This is a thermal insulation test diagram of a foam-based thermal insulation and electro-hydraulic material according to an embodiment of the present invention. Figure 5 and Figure 6 As shown in the figure, the foam-based thermal insulation and electro-electric material provided in this embodiment of the invention has good thermal insulation and heat resistance properties.

[0058] Example 3

[0059] Figure 7 This is a schematic diagram of a high-temperature vibration sensor based on a foam-based thermally insulated triboelectric nanogenerator, according to an embodiment of the present invention. Figure 7 As shown, it includes a friction layer 1 and two electrodes 2. The friction layer 1 is disposed between the two electrodes 2. The friction layer 1 is made of a foam-based thermal insulation and electro-hydraulic material provided in the embodiments of the present invention.

[0060] Preferably, the thickness of the friction layer 1 includes 1mm-3mm.

[0061] Preferably, both electrodes 2 are copper conductive strips.

[0062] Preferably, a PVC layer 3 is also provided on the outer side of the two electrodes 2.

[0063] In one optional embodiment of the present invention, the high-temperature vibration sensor has a size of 4cm×4cm×1-3mm.

[0064] Figure 8 This is a voltage, current, and stability test diagram of a high-temperature vibration sensor provided according to an embodiment of the present invention.

[0065] This invention presents an embodiment of a high-temperature vibration sensor, which undergoes output performance and heat resistance testing under contact separation mode. The test results are as follows: Figure 9 As shown.

[0066] Figure 10 This is a power supply test diagram for a high-temperature vibration sensor provided according to an embodiment of the present invention.

[0067] Depend on Figures 8-10 As can be seen, the high-temperature vibration sensor provided in this embodiment of the invention has a maximum output voltage of 186V and a short-circuit current of 0.3μA / cm2 at room temperature; and a maximum output voltage of 106V and a short-circuit current of 0.16μA / cm2 at 200℃. The maximum heat resistance temperature is 200℃.

[0068] Triboelectric nanogenerators are an innovative energy harvesting technology that generates electrical charge through the contact and separation of materials, converting mechanical energy into electrical energy. This invention utilizes the working principle of triboelectric nanogenerators, employing a foam-based thermally insulated triboelectric nanogenerator as a high-temperature vibration sensor. This sensor exhibits excellent thermal insulation performance and a stable output signal when detecting vibrations in vibrating bodies, solving the technical problem that traditional sensors suffer from decreased stability and accuracy, or even malfunction and loss, under high-temperature and long-term operating conditions, thus failing to meet long-term operational requirements.

[0069] Example 4

[0070] Figure 11 This is a flowchart illustrating a fault detection method for a high-temperature vibration sensor based on a foam-based thermally insulating triboelectric nanogenerator, according to an embodiment of the present invention. Figure 11 As shown, the method specifically includes the following steps:

[0071] Step S1102: Based on the high-temperature vibration sensor, acquire the vibration signal data of the vibrating body to be tested.

[0072] Optionally, the vibrating body to be tested includes an engine and an air conditioning compressor.

[0073] Specifically, a foam-based thermally insulating triboelectric nanogenerator is installed as a high-temperature vibration sensor on the body of an engine or air conditioning compressor, and connected to a data acquisition device via conductive copper wire to collect signal data under different vibration conditions.

[0074] Step S1104: Determine whether the vibration signal data is within the preset vibration data range; if yes, proceed to step S1106; if no, proceed to step S1108.

[0075] Step S1106: Determine that the vibrating machine body to be tested is in a fault-free state.

[0076] Step S1108: Determine that the vibrating machine body to be tested is in a fault state, and determine the fault type of the vibrating machine body to be tested based on the preset fault database.

[0077] Specifically, the method provided in this embodiment of the invention further includes acquiring a preset vibration data range and a preset fault database before performing fault detection on the vibrating machine body to be tested. Specifically, it includes the following steps:

[0078] Step S101: Based on the high-temperature vibration sensor, acquire the normal vibration dataset of the vibrating body under fault-free condition;

[0079] Step S102: Preprocess the normal vibration dataset to obtain a preset vibration data range;

[0080] Step S103: Based on the high-temperature vibration sensor, acquire the fault vibration dataset of the vibrating body under different fault states;

[0081] Step S104: Preprocess the fault vibration dataset to obtain a preset fault database; the preset fault database includes the fault vibration data range corresponding to different fault types.

[0082] Specifically, step S1108 also includes the following step: determining the fault type corresponding to the fault vibration data range where the vibration signal data is located as the fault type of the vibrating body to be tested.

[0083] Figure 12 This is an abnormal vibration detection diagram of a high-temperature vibration sensor provided according to an embodiment of the present invention. Figure 13 This is a fault detection output signal and stability diagram of a high-temperature vibration sensor provided according to an embodiment of the present invention.

[0084] As described above, the embodiments of the present invention provide a foam-based thermal insulation and electro-hydraulic material, a preparation method, a sensor, and a fault detection method, which have the following technical advantages compared with the prior art:

[0085] (1) A flexible composite foam electro-electric material with heat insulation, flame retardancy and good mechanical properties was prepared by a low-cost and simple synthesis method.

[0086] (2) The triboelectric nanogenerator unit with flexible structure design can be flexibly designed in size according to the invention requirements, which enhances the collection efficiency of mechanical energy to electrical energy and expands the application scenarios.

[0087] (3) Foam-based thermally insulated triboelectric nanogenerators can be used as high-temperature vibration sensors to withstand the operation of engines and air conditioning compressors in high-temperature environments for a long time, and can achieve efficient energy harvesting and intelligent sensing and detection applications.

[0088] (4) This invention can be used as a high-temperature vibration sensor to detect abnormal vibration states of engines and air conditioning compressors, and can directly power intelligent electronic devices or sensors. After adding a supercapacitor to the circuit management to form a self-powered system, vibration energy can be directly collected, which can simplify circuit management and continuously monitor the status of engines and air conditioning compressors.

[0089] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for preparing a foam-based thermal insulation and electrostatic material, characterized in that, include: A mixture of glucose and ammonium chloride is added to deionized water to form a homogeneous solution; Perlite powder was added to the homogeneous solution and stirred, and then calcined under a nitrogen atmosphere to obtain a black foamy solid. The black foamy solid was ground into perlite-graphene composite particles; The perlite-graphene composite particles are mixed into PDMS prepolymer at a preset doping ratio and then stirred and cured to obtain a foam-based thermal insulation and electrostatic material. The calcination under a nitrogen atmosphere includes calcination at a temperature of 900℃-1350℃ for 3-5 hours under a nitrogen atmosphere.

2. The method according to claim 1, characterized in that, The preset doping ratio includes 2wt%-10wt%.

3. A foam-based thermal insulation and electrostatic material, characterized in that, It is prepared based on the method for preparing foam-based thermal insulation and electro-hydraulic material according to any one of claims 1-2.

4. A high-temperature vibration sensor based on a foam-based thermally insulating triboelectric nanogenerator, comprising a friction layer and two electrodes, wherein the friction layer is disposed between the two electrodes, characterized in that, The friction layer is made of a foam-based thermal insulation and electro-hydraulic material as described in claim 3.

5. The high-temperature vibration sensor based on a foam-based thermally insulating triboelectric nanogenerator according to claim 4, characterized in that, The thickness of the friction layer ranges from 1 mm to 3 mm.

6. The high-temperature vibration sensor based on a foam-based thermally insulating triboelectric nanogenerator according to claim 4, characterized in that, Both electrodes are copper conductive strips.

7. A fault detection method for a high-temperature vibration sensor based on a foam-based thermally insulating triboelectric nanogenerator as described in any one of claims 4-6, characterized in that, include: Based on the high-temperature vibration sensor, the vibration signal data of the vibrating machine body under test is acquired; Determine whether the vibration signal data is within the preset vibration data range; If so, the vibrating machine body to be tested is determined to be in a fault-free state; If not, the vibrating machine body to be tested is determined to be in a fault state, and the fault type of the vibrating machine body to be tested is determined based on a preset fault database.

8. The fault detection method according to claim 7, characterized in that, The method further includes: Based on the high-temperature vibration sensor, a normal vibration dataset of the vibrating body under fault-free conditions is obtained; The normal vibration dataset is preprocessed to obtain a preset vibration data range; Based on the high-temperature vibration sensor, the fault vibration dataset of the tested vibrating body under different fault states is obtained; The fault vibration dataset is preprocessed to obtain a preset fault database; the preset fault database includes fault vibration data ranges corresponding to different fault types.

9. The fault detection method according to claim 8, characterized in that, The fault type of the vibrating machine body to be tested is determined based on a preset fault database, including: The fault type corresponding to the fault vibration data range where the vibration signal data is located is determined as the fault type of the vibrating machine body to be tested.

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