阅读说明：本技术 一种模拟飞行器真实加热模式的石英灯热考核方法 (Quartz lamp heat assessment method for simulating real heating mode of aircraft ) 是由 郭建业 李文静 杨洁颖 苏力军 裴雨辰 于 2020-11-09 设计创作，主要内容包括：本发明涉及一种模拟隔热材料在飞行器中真实加热模式的石英灯热考核方法,所述热考核方法包括如下步骤：(1)将测温热电偶正负极连接在一起；(2)将测温热电偶测点固定于防热板上；(3)将纤维布覆盖热电偶焊点,铺设于防热板上；(4)采用混合剂浸渍纤维布,使其在原位进行复合反应生成纤维增强复合材料,从而将热电偶固定于防热板上；(5)将所述纤维增强复合材料进行固化,使热电偶固定于防热板上。本发明可以很好模拟飞行器的真实加热状态及隔热材料的真实受热环境,为耐高温隔热材料的试验验证及高温隔热性能评价提供更加可靠的方法。(The invention relates to a quartz lamp heat assessment method for simulating a real heating mode of a thermal insulation material in an aircraft, which comprises the following steps: (1) connecting the positive electrode and the negative electrode of the temperature thermocouple together; (2) fixing a measuring point of a temperature thermocouple on a heat-proof plate; (3) covering the thermocouple welding spots with fiber cloth, and laying the fiber cloth on the heat-proof plate; (4) impregnating fiber cloth with the mixture to carry out composite reaction in situ to generate a fiber reinforced composite material, so that the thermocouple is fixed on the heat-proof plate; (5) and curing the fiber reinforced composite material to fix the thermocouple on the heat-proof plate. The invention can well simulate the real heating state of the aircraft and the real heating environment of the heat insulation material, and provides a more reliable method for the test verification of the high-temperature-resistant heat insulation material and the evaluation of the high-temperature heat insulation performance.)

1. A quartz lamp thermal assessment method for simulating a real heating mode of an insulating material in an aircraft is characterized by comprising the following steps:

(1) connecting the positive electrode and the negative electrode of the temperature thermocouple together;

(2) fixing a measuring point of a temperature thermocouple on a heat-proof plate;

(3) covering the thermocouple welding spots with fiber cloth, and laying the fiber cloth on the heat-proof plate;

(4) soaking fiber cloth with a mixture containing an adhesive and a curing agent, and carrying out a composite reaction in situ to generate a fiber reinforced composite material, so that the thermocouple is fixed on the heat-proof plate;

(5) and curing the fiber reinforced composite material to fix the thermocouple on the heat-proof plate.

2. The thermal assessment method according to claim 1, wherein:

in the step (1), the thermocouple is a K-type thermocouple;

the connection is welding;

preferably, the welding is performed using a spot welder;

more preferably, the spot welder is a micro energy storage spot welder.

3. The thermal assessment method according to claim 1, wherein:

the heat-proof plate is a ceramic heat-proof plate;

preferably, the heat-proof plate is a carbon fiber reinforced silicon carbide ceramic composite material;

more preferably, the heat-proof plate has a size of (100 to 200) × (100 to 200) mm and a thickness of 1 to 3 mm.

4. The thermal assessment method according to claim 1, wherein:

in the step (2), the measuring points of the temperature thermocouple are fixed on the heat-proof plate in a mode of bonding through a high-temperature adhesive tape;

preferably, the high-temperature adhesive tape is a fiber adhesive tape;

more preferably, the high-temperature adhesive tape is a high-temperature-resistant glass cloth adhesive tape.

5. The thermal assessment method according to claim 1, wherein:

in the step (3), the fiber cloth is made of a material selected from the group consisting of quartz fibers, high silica fibers, mullite fibers and alumina silicate fibers;

preferably, the linear density of the yarns of the fiber cloth is 20-50 t; and/or

The twist of the yarn of the fiber cloth is 50-80T/M;

more preferably, the linear density of the yarns of the fiber cloth is 20, 25, 30 t; and/or the yarn of the fiber cloth has a twist of 50, 55 and 60T/M.

6. The thermal assessment method according to claim 1, wherein:

in the step (3), the warp density and the weft density of the fiber cloth are (10-40 pieces/cm) × (10-20 pieces/cm);

preferably, the warp density x weft density of the fiber cloth is 12 x 12 pieces/cm, 14 x 14 pieces/cm;

more preferably, the thickness of the fiber cloth is 0.1 to 0.2 mm.

7. The thermal assessment method according to claim 1, wherein:

in the step (3), the paving method is tiling; and/or

The laying is carried out by adopting an adhesive tape for bonding;

preferably, the adhesive tape is a high-temperature-resistant glass cloth adhesive tape;

more preferably, the adhesive tape is the same adhesive tape used in the step (2);

more preferably, the periphery of the fiber cloth is bonded by using an adhesive tape.

8. The thermal assessment method according to claim 1, wherein:

in the step (4), the curing agent is a metal oxide or inorganic salt curing agent, and the adhesive is an inorganic high-temperature adhesive;

preferably, the adhesive is selected from the group consisting of silicate-based adhesives, phosphate-based adhesives, and oxide-based adhesives;

more preferably, when the adhesive is a phosphate adhesive, a single component or a double component is adopted;

more preferably, the phosphate-based adhesive is a J-244 phosphate-based adhesive.

9. The thermal assessment method according to claim 1, wherein:

in the step (4), the mixing agent is prepared by uniformly mixing an adhesive and a curing agent;

preferably, the impregnation is to uniformly spread the mixture on the fiber cloth.

10. The thermal assessment method according to claim 1, wherein:

in the step (5), the curing temperature is between room temperature and 80 ℃;

preferably, the curing temperature is 80 ℃.

Technical Field

The invention relates to the technical field of thermal test of thermal insulation materials, in particular to a quartz lamp thermal assessment method for simulating a real heating mode of a thermal insulation material in an aircraft.

Background

The aerospace craft faces a severe aerodynamic thermal environment when flying in the atmospheric layer, a thermal protection system needs to be arranged on the surface and inside of the aerospace craft, along with the development of supersonic velocity and hypersonic velocity technology, the severe high-temperature environment on the surface of the aerospace craft promotes the development of the thermal protection system in a direction of super-heat prevention and heat insulation, the traditional method is that a ceramic heat-proof material is arranged on the outermost layer and used for resisting the erosion of heat flow, and because the thermal conductivity of a ceramic material is higher and the heat insulation performance is poorer, a heat-insulating material with low thermal conductivity needs to be arranged on the inner layer of the ceramic material and used for preventing the.

A great part of high cost of aerospace research and development is reflected in test verification, a common wind tunnel test costs hundreds of thousands of times, the heat insulation performance of the heat insulation material is indispensible to be evaluated while the heat insulation material is researched and developed, and how to simulate the thermal environment of the heat insulation material in an aircraft is more important in the evaluation process.

A quartz lamp examination test is widely used as a test mode for simulating pneumatic heating of an aircraft, a temperature control plate of a traditional quartz lamp heating test is generally a metal plate, a thermocouple is fixed on the hot surface of the metal plate in a welding mode, the quartz lamp heating test is suitable for simulating the environment that the outer side of a heat insulation material is a metal wall surface, and as the heat insulation material is increasingly used on the inner side of a ceramic heat-proof material, the metal plate is used as the temperature control plate to carry out the quartz lamp heating test, so that the real heating environment of the heat insulation material can not be accurately simulated, in view of the fact that the pneumatic heating is transmitted to the internal heat insulation material through the ceramic heat-proof material, the ceramic material is used as the temperature control plate to better simulate the real heating environment of the heat insulation material, but because the ceramic material is not conductive, the thermocouple cannot be fixed in a common welding mode, when the test temperature is above 400 ℃, the high-temperature adhesive tape can fail.

Therefore, in view of the above problems, the present invention provides a new quartz lamp high temperature thermal assessment method for simulating the real heating mode of an insulation material in an aircraft. The test method takes the ceramic plate as the temperature control plate, takes the fiber cloth as the reinforcement, takes the high-temperature-resistant adhesive as the matrix, takes the high-temperature adhesive tape as the auxiliary tool, and adopts the mode of fixing the thermocouple on the surfaces of the ceramic plate and the thermocouple welding spot in an in-situ composite reaction manner, the thermocouple welding spot is tightly attached to the surface of the ceramic plate, the quartz lamp has good heating temperature control, the real heating state of an aircraft and the real heating environment of the heat insulation material can be well simulated, and the test method provides a more reliable method for the test verification of the high-temperature-resistant heat insulation material and the evaluation of the high-temperature.

Disclosure of Invention

Technical problem to be solved

The invention aims to solve the technical problem that the existing quartz lamp high-temperature thermal examination test cannot truly simulate the real heating state of a thermal insulation material on an aircraft.

(II) technical scheme

In order to solve the technical problem, the invention provides a quartz lamp thermal assessment method for simulating a real heating mode of a thermal insulation material in an aircraft, which comprises the following steps:

(1) connecting the positive electrode and the negative electrode of the temperature thermocouple together;

(2) fixing a measuring point of a temperature thermocouple on a heat-proof plate;

(3) covering the thermocouple welding spots with fiber cloth, and laying the fiber cloth on the heat-proof plate;

(4) soaking fiber cloth with a mixture containing an adhesive and a curing agent, and carrying out a composite reaction in situ to generate a fiber reinforced composite material, so that the thermocouple is fixed on the heat-proof plate;

(5) and curing the fiber reinforced composite material to fix the thermocouple on the heat-proof plate.

(III) advantageous effects

The technical scheme of the invention has the following advantages:

the invention takes a ceramic plate as a temperature control plate, takes fiber cloth as a reinforcement, takes a high-temperature-resistant adhesive as a matrix and takes a high-temperature adhesive tape as an auxiliary tool, and adopts a mode of fixing a thermocouple on the surfaces of a ceramic heat-proof plate and a thermocouple welding spot in an in-situ composite reaction, the thermocouple welding spot is tightly attached to the surface of the ceramic heat-proof plate, the heating temperature control of a quartz lamp is good, and the heating temperature control precision is within +/-2 ℃. Compared with the traditional metal plate temperature control method for heating by using a quartz lamp, the method can more reliably simulate the real heating environment of the thermal insulation material on the aircraft, provides more reliable data for the high-temperature thermal insulation performance evaluation of the thermal insulation material, and reduces the test verification cost of the thermal insulation material. Has wide application prospect in the field of evaluation of high-temperature heat-insulating property of heat-insulating materials.

Drawings

FIG. 1 is a flow chart of a quartz lamp thermal qualification method for simulating a true heating mode of an aircraft;

FIG. 2 is a schematic view of the installation of a thermal examination test piece of a quartz lamp. The reference numbers are as follows: 1. the heat insulation material comprises a mixing agent, 2 parts of fiber cloth, 3 parts of a thermocouple, 4 parts of a heat insulation material, 5 parts of a ceramic heat insulation plate.

Detailed Description

In order to make the objects, 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 with reference to the embodiments of the present invention, and it is obvious that the described embodiments are a part of the embodiments of the present invention, but not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

The invention provides a quartz lamp heat assessment method for simulating a real heating mode of a thermal insulation material in an aircraft, which comprises the following steps:

(1) according to the temperature measurement principle, connecting the positive electrode and the negative electrode of a temperature thermocouple together;

(2) preliminarily fixing the measuring point of the temperature thermocouple on the heat-proof plate;

(3) covering the thermocouple welding spots with fiber cloth, and laying the fiber cloth on the heat-proof plate;

(4) soaking fiber cloth with a mixture containing an adhesive and a curing agent to perform a composite reaction in situ to generate a fiber reinforced composite material, so that the thermocouple is further fixed on the heat-proof plate;

(5) and curing the fiber reinforced composite material to further fix the thermocouple on the heat-proof plate.

The installation schematic diagram of the thermal check of the quartz lamp is shown in fig. 2. As can be seen from FIG. 2, the examined heat insulating material 4 to be inspected is located on one side of the ceramic heat shield plate 5; the measuring points (namely the connecting points of the anode and the cathode are fixed on the other side of the ceramic heat-proof plate 5, the fiber cloth 2 covers the welding points of the thermocouple and is laid on the ceramic heat-proof plate 5, and the fiber cloth 2 is soaked by the mixture 1 to carry out composite reaction in situ, and then the thermocouple 3 is fixed on the ceramic heat-proof plate 5.

According to some preferred embodiments, in step (1), the temperature thermocouple needs to meet the basic temperature measurement requirement and also needs to meet the temperature resistance requirement, and can be a commercially available product, and preferably, the thermocouple is a K-type thermocouple.

According to some preferred embodiments, in step (1), for good connection, the connection is welding;

preferably, the welding is performed using a spot welder; the common spot welding machine can be a micro energy storage welding machine.

According to some preferred embodiments, the heat shield is a ceramic heat shield; the ceramic heat-proof plate is made of the same material and process as the actual product, for example, the carbon fiber reinforced silicon carbide ceramic composite material which is a common material for the external heat-proof of the existing aerospace craft.

According to some preferred embodiments, the heat shield has a size of (100 to 200) × (100 to 200) mm and a thickness of 1 to 3 mm. According to some preferred embodiments, in the step (2), the temperature thermocouple measuring points (i.e. the positive and negative connecting points) are fixed on the heat-proof plate by means of high-temperature adhesive tape; the high-temperature adhesive tape has the function similar to that of an auxiliary fixing tool, so that on one hand, the normal-temperature adhesive property is required to be ensured, and on the other hand, the system is not influenced negatively at high temperature;

preferably, the high-temperature adhesive tape is a fiber adhesive tape;

more preferably, the high-temperature adhesive tape is a high-temperature-resistant glass cloth adhesive tape. For example, the thermocouple welding point can be 3M69 glass cloth adhesive tape, the thermocouple welding point is ensured to be attached to the ceramic heat-proof plate during bonding, in order to avoid the influence of the high-temperature adhesive tape on heat loading, the bonding area of the high-temperature adhesive tape is not too large, the thermocouple can be fixed, and the large-area bonding of the high-temperature adhesive tape is avoided.

According to some preferred embodiments, in step (3), the material of the fiber cloth is selected from the group consisting of quartz fibers, high silica fibers, mullite fibers, and alumina silicate fibers; the fibers need to meet the temperature resistance requirements for quartz lamp heating, for example, 1000 ℃.

Preferably, the linear density of the yarns of the fiber cloth is 20-50 t; for example, 20, 25, 30, 35, 40, 45, 50 t; and/or

The twist of the yarn of the fiber cloth is 50-80T/M; for example, it may be 50, 55, 60, 65, 70, 75, 80T/M;

in some more preferred embodiments, the fiber yarn has a linear density of 20, 25, 30T, and the fiber yarn has a twist of 50, 55, 60T/M;

according to some preferred embodiments, the fiber cloth has a warp density x a weft density of (10 to 40 threads/cm) × (10 to 20 threads/cm); for example, the number of the particles may be 12 × 10, 12 × 12, 14 × 14, 18 × 18, 20 × 20, 26 × 18, 30 × 20, or 34 × 20.

Preferably, the warp density x weft density of the fiber cloth is 12 x 12 pieces/cm, 14 x 14 pieces/cm;

more preferably, the thickness of the fiber cloth is 0.1 to 0.2 mm.

In terms of the linear density of the fiber yarn, the larger the linear density, the larger the thickness of the fiber cloth, and the poorer the wettability of the fiber cloth, and in terms of the twist of the fiber yarn, the smaller the twist, the poorer the preparation manufacturability, the larger the twist, the larger the yarn strength, and the poorer the wettability of the yarn. Regarding the warp density and the weft density of the fiber yarn, the denser the yarn is, the poorer the wettability of the fiber cloth is. In order to ensure that the high-temperature adhesive can fully impregnate the fiber cloth, the linear density, the twist degree, the warp density and the weft density of the selected fiber yarns are not too high.

According to some preferred embodiments, in step (3), the paving method is tiling; and/or

In order to fix the fiber cloth and the heat-proof plate, the laying adopts adhesive tapes for bonding;

preferably, the adhesive tape is a high-temperature-resistant glass cloth adhesive tape;

more preferably, the adhesive tape is the same adhesive tape used in the step (2); it should be noted that the bonding can guarantee the laminating of fibre cloth and heat protection board can, the bonding area should not be too big, otherwise can influence the accuracy of heat loading simulation.

In some more preferred embodiments, the fiber cloth is bonded around with a glass cloth tape.

The high temperature resistant adhesive plays a role of a composite material matrix in the invention, and the high temperature resistant adhesive, the fiber cloth, the thermocouple and the ceramic plate are firmly fixed together by compounding the adhesive and the fiber cloth and compounding the adhesive and the fiber cloth in situ on the electric shock of the heat-proof plate and the thermocouple to form the fiber reinforced adhesive composite material.

According to some preferred embodiments, in the step (4), the curing agent is a metal oxide or inorganic salt curing agent, and the adhesive is an inorganic high-temperature adhesive; the adhesive can be silicate adhesive, phosphate adhesive and oxide adhesive, and the adhesive needs to meet the temperature resistance requirement of quartz lamp examination and heating, for example, the temperature resistance is 1000 ℃, the phosphate adhesive is preferred, and the adhesive can be single-component or double-component;

in some more preferred embodiments, J-244 phosphate-based adhesives may be used.

Curing is an important step in the formation of composite materials by which the mixture components are fully reacted.

According to some preferred embodiments, in the step (4), the mixture is prepared by uniformly mixing the adhesive and the curing agent;

preferably, the impregnation is to uniformly spread the mixture on the fiber cloth.

According to some preferred embodiments, in step (5), the temperature of the curing is between room temperature (e.g., 20-30 ℃) and 80 ℃; the higher the curing temperature, the shorter the curing time, and preferably, the curing temperature is 80 ℃.

Example 1

Step 1, providing a ceramic heat-proof plate and a temperature thermocouple

The method comprises the steps of selecting a carbon fiber reinforced silicon carbide (C/SiC) ceramic heat-proof plate with the size of 200 x 200mm and the thickness of 2mm, wherein the ceramic material is the type of common materials for heat-proof outside an aircraft, and selecting a K-type thermocouple as the thermocouple.

Step 2, welding the positive electrode and the negative electrode of the temperature thermocouple through a spot welding machine

According to the temperature measurement principle, a spot welder is used for welding the positive electrode and the negative electrode of the thermocouple together to serve as a temperature measurement point, and the spot welder is a miniature energy storage spot welder produced by Beijing century Revwei science and technology Limited company, and is provided with a power supply of 220VAC and a power of 50W.

Step 3, fixing the temperature thermocouple measuring point on the ceramic heat-proof plate through a high-temperature adhesive tape

3M69 glass cloth adhesive tape is selected for use as the high-temperature adhesive tape, the high-temperature adhesive tape is cut into 20mm × 5mm, the positions 10mm away from the two sides of the welding spot are bonded on the ceramic heat-proof plate by the cut adhesive tape, the thermocouple welding spot is bonded with the ceramic heat-proof plate during bonding, the influence of the high-temperature adhesive tape on the accuracy of the simulated real heated state is considered, and the large-area bonding of the high-temperature adhesive tape is avoided.

Step 4, providing fiber cloth

The fiber cloth is made of quartz fibers, the linear density of the fiber yarns is 25T, the twist of the fiber yarns is 55T/M, the thickness of the woven quartz fiber cloth is 0.1mm, and the quartz fiber cloth is cut into 10 x 10mm for later use.

Step 5, arranging the fibers on a ceramic heat-proof plate

Covering the thermocouple welding spot with quartz fiber cloth, and spreading on the ceramic heat-proof plate. The periphery of the quartz fiber cloth is bonded on the ceramic heat-proof plate by using a 3M69 glass cloth adhesive tape, the width of the glass cloth adhesive tape is 3mm, and the length of the glass cloth adhesive tape is 10mm consistent with the length of the edge of the quartz fiber cloth.

Step 6, dipping the high-temperature-resistant adhesive into fiber cloth to produce fiber-reinforced composite material through in-situ composite reaction, and fixing the thermocouple on the ceramic heat-proof plate

The high-temperature adhesive is J-244 phosphate adhesive. Weighing 20g of adhesive component and 20g of curing agent component, uniformly mixing the two components, uniformly coating the mixture on quartz fiber cloth by using a shovel, fully soaking the quartz fiber cloth by using the adhesive, leveling the adhesive, and generating the quartz fiber cloth reinforced phosphate adhesive composite material on a ceramic heat-proof plate, wherein the area of the adhesive is not more than 3mm from the outer edge of the quartz fiber cloth.

Step 7, curing, namely fixing the thermocouple on the ceramic heat-proof plate

And (3) putting the heat-proof plate bonded with the thermocouple into an oven, setting the temperature to be 80 ℃, and curing the quartz fiber cloth reinforced phosphate adhesive composite material generated on the ceramic heat-proof plate for 4 hours.

The method is characterized in that a mullite fiber reinforced silica aerogel thermal insulation material is taken as an assessment target, the size of the aerogel thermal insulation material is 150 mm-150 mm, the thickness of the aerogel thermal insulation material is 20mm, a quartz lamp heating assessment test is carried out by using the ceramic plate temperature control method for the composite material in-situ curing and bonding thermocouple, the assessment temperature is 400 ℃, the assessment time is 1000s, the heating rate is 10 ℃/s, namely the preset temperature control temperature is increased from room temperature to 400 ℃ at the heating rate of 10 ℃/s, then the temperature is preserved at 400 ℃, and the assessment is finished when the total assessment time is 1000 s. The assessment result is as follows: the back temperature is 86 ℃, and the temperature control precision is +/-1.5 ℃ (the temperature control precision is the maximum value of the temperature difference between the measured temperature of each test point on the measured temperature change curve of the thermocouple and the temperature of the corresponding time point on the preset temperature control temperature curve of the ceramic plate).

Example 2

This example 2 is substantially the same as example 1 except that: the examination temperature was 500 ℃.

Example 3

This example 3 is substantially the same as example 1 except that: the examination temperature was 600 ℃.

Example 4

This example 4 is substantially the same as example 1 except that: the examination temperature was 700 ℃.

Example 5

This example 5 is substantially the same as example 1 except that: the examination temperature was 800 ℃.

Example 6

This example 6 is substantially the same as example 1 except that: the examination temperature was 900 ℃.

Example 7

This example 7 is substantially the same as example 1 except that: the examination temperature was 1000 ℃.

TABLE 1 examination result data of quartz lamps of the examples

Examples	Examination temperature (. degree.C.)	Back temperature (. degree.C.)	Temperature control accuracy (. degree. C.)
				Example 1	400	86	±1.5
Example 2	500	104	±1.5
				Example 3	600	122	±1.5
Example 4	700	142	±1.5
				Example 5	800	161	±1.5
Example 6	900	182	±1.5
				Example 7	1000	198	±1.5

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.