A thermal protection test piece suitable for a micro-wind tunnel test device

Abstract

This invention provides a thermal protection specimen suitable for microwind tunnel testing equipment. The thermal protection specimen includes a backplate and a heat-insulating layer disposed on the back of the backplate. A heat-blocking layer is located in the center of the backplate, dividing it into a central region and an outer frame region. The central region is the microwind tunnel thermal protection testing area. By using a heat-blocking layer to divide the backplate into a central region and an outer frame region, heat is blocked between them, preventing heat conduction and effectively improving the validity and repeatability of measurement data. This avoids the problem of excessive heat loss due to excessive specimen size, which could distort test data. This invention can guide the thermal protection design and experimental verification of theoretical methods for hypersonic vehicles.

Description

Technical Field

[0001] This invention relates to the field of thermal protection technology for hypersonic vehicles, and in particular to a thermal protection specimen suitable for microwind tunnel testing equipment. Background Technology

[0002] Hypersonic vehicles (generally referring to vehicles with speeds exceeding Mach 5) undergo prolonged hypersonic maneuvering within the atmosphere, facing continuous and severe aerodynamic heating, with peak heat flux reaching 1 MW / m³. 2 The total heating capacity is 5×10 3 MJ / m 2 Hypersonic vehicles experience high surface temperatures. To prevent them from burning up due to aerodynamic heating, thermal protection designs are necessary. Different thermal protection schemes offer varying degrees of protection. To find the optimal design, ground-based dynamic thermal material screening tests are required. When these tests transition to mass production, each product needs to undergo sample testing at the specimen level to ensure consistent product quality. Microwind tunnel testing equipment is relatively easy to operate, has low operating costs, and offers good controllability, providing feasibility for specimen-level testing, thermal protection material R&D, and batch product consistency testing. However, existing microwind tunnel testing equipment typically uses 100mm x 100mm square block specimens for thermal protection, while the uniform flow field area in a microwind tunnel is generally around φ20mm. Therefore, the existing specimens are too large for the uniform flow field area, leading to significant heat loss and uneven heating, resulting in high data distortion. Summary of the Invention

[0003] This invention provides a thermal protection specimen suitable for micro wind tunnel testing equipment to solve the aforementioned technical problems.

[0004] The present invention provides a thermal protection specimen suitable for micro wind tunnel testing equipment. The thermal protection specimen includes a thermal protection specimen back plate and a heat-insulating layer disposed on the back of the thermal protection specimen back plate. The thermal protection specimen back plate has a heat-blocking layer in the middle, which divides the thermal protection specimen back plate into a central area and an outer frame area. The central area is the micro wind tunnel thermal protection test area.

[0005] Preferably, the heat-blocking layer only divides the back plate of the heat protection specimen.

[0006] Preferably, the heat-blocking layer is a square heat-blocking layer centered on the back plate of the heat protection specimen.

[0007] Preferably, the heat-blocking layer is an annular heat-blocking layer with the center of the back plate of the heat protection specimen as the center.

[0008] Preferably, the annular heat-blocking layer consists of multiple blocking through holes arranged in a ring around the center of the back plate of the heat protection specimen.

[0009] Preferably, the blocking through hole is provided only through the back plate of the thermal protection specimen.

[0010] Preferably, the annular heat-blocking layer is a blocking ring with the center of the back plate of the heat protection specimen as the center, and the blocking ring divides the back plate of the heat protection specimen into a central region and an outer frame region.

[0011] Preferably, the blocking ring is filled with heat-insulating material.

[0012] Preferably, the thermal insulation material is a material with low thermal conductivity.

[0013] Preferably, the size of the heat-blocking layer is consistent with the range of the uniform flow field in the micro-wind tunnel test.

[0014] The present invention discloses a thermal protection specimen suitable for microwind tunnel testing equipment. By setting a thermal blocking layer, the back plate of the thermal protection specimen is divided into a central region and an outer frame region. The thermal blocking layer achieves heat blockage between the central region and the outer frame region, and heat will not be conducted between them. This effectively improves the validity and repeatability of measurement data and avoids the problem of large heat loss due to excessive specimen size, which would lead to data distortion. It can guide the thermal protection design and experimental verification of theoretical methods for hypersonic aircraft.

[0015] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0016] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0017] Figure 1 This is a three-dimensional structural diagram of the thermal protection specimen suitable for micro wind tunnel testing equipment according to an embodiment of the present invention;

[0018] Figure 2 This is a front view of the thermal protection specimen suitable for micro wind tunnel testing equipment as described in an embodiment of the present invention;

[0019] Figure 3 This is a side sectional view of the thermal protection specimen suitable for micro wind tunnel testing equipment as described in an embodiment of the present invention;

[0020] Figure 4 This is another front view of the thermal protection specimen for micro wind tunnel testing equipment described in this embodiment of the invention. Detailed Implementation

[0021] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0022] This invention provides a thermal protection specimen suitable for micro wind tunnel testing equipment, such as... Figures 1 to 4 As shown, the thermal protection specimen includes a thermal protection specimen back plate 1 and a heat-insulating layer 2 disposed on the back of the thermal protection specimen back plate 1; wherein, a heat-blocking layer 3 is provided in the middle of the thermal protection specimen back plate 1, the heat-blocking layer 3 dividing the thermal protection specimen back plate 1 into a central region 11 and an outer frame region 12, the central region 11 being the micro-wind tunnel thermal protection test area. Preferably, the size of the heat-blocking layer 3 is consistent with the uniform region of the flow field in the micro-wind tunnel test; and as... Figure 3 As shown, the heat-blocking layer 3 only divides the back plate 1 of the heat protection specimen.

[0023] By setting a heat-blocking layer 3, the back plate 1 of the thermal protection specimen is divided into a central region 11 and an outer frame region 12. The heat is blocked between the central region 11 and the outer frame region 12 through the heat-blocking layer 3, and there is no heat conduction between them. This effectively improves the validity and repeatability of the measurement data and avoids the problem of large heat loss due to the large area of ​​the specimen, which would lead to the distortion of the test data. It can guide the thermal protection design and experimental verification of theoretical methods for hypersonic aircraft.

[0024] More preferably, the heat-blocking layer 3 can be a square heat-blocking layer 3 centered on the center of the back plate 1 of the heat protection specimen; or it can be an annular heat-blocking layer 3 centered on the center of the back plate 1 of the heat protection specimen. Taking the annular heat-blocking layer 3 as an example, as follows... Figure 4 As shown, the annular heat-blocking layer 3 can be multiple blocking through-holes arranged in a ring around the center of the heat protection specimen backplate 1. These blocking through-holes only penetrate the heat protection specimen backplate 1. Further as... Figure 2 As shown, the annular heat-blocking layer 3 can also be a blocking ring with the center of the heat protection specimen back plate 1 as the center, and the blocking ring divides the heat protection specimen back plate 1 into a central region 11 and an outer frame region 12.

[0025] The specific structure of the heat-blocking layer 3 varies depending on the temperature range of the micro-wind tunnel thermal protection test. Preferably, when the temperature range of the micro-wind tunnel thermal protection test is below 100 degrees Celsius, the heat-blocking layer 3 can adopt a structure with blocked through holes; when the temperature range exceeds 100 degrees Celsius, the heat-blocking layer 3 can adopt a structure with a blocking ring. Furthermore, when the temperature range of the micro-wind tunnel thermal protection test is between 100-120 degrees Celsius, thermal insulation material is further filled inside the blocking ring to further improve the thermal blocking effect between the central region 11 and the outer frame region 12. Preferably, the thermal insulation material is aerogel.

[0026] The following are specific test data obtained using a thermal protection specimen suitable for micro wind tunnel testing equipment provided by this invention:

[0027] Heat flux density: 240kW / m 2 Enthalpy range: 2.23 MJ / kg, pressure: 8.5 kPa, orbital time: 1000 s, the material of the back plate 1 of the thermal protection specimen is quartz phenolic resin + aluminum alloy, the thickness of the heat-resistant material is 10 mm, the thickness of the back plate 1 of the thermal protection specimen is 3 mm, its outer frame size is 98 mm × 98 mm; the inner circle diameter is φ20 mm; the diameter and width of the annular heat-blocking layer 3 are 3 mm, the theoretically calculated outer wall temperature is 896℃, the inner wall temperature is 349℃, and the error between the experimental and theoretical calculation results is within 10%.

[0028] As can be seen from the above data, the thermal protection test using the thermal protection specimen suitable for micro-wind tunnel test equipment described in this invention has high validity and repeatability of the measurement data, which can guide the thermal protection design of hypersonic vehicles and the experimental verification of theoretical methods.

[0029] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A thermal protection specimen suitable for micro wind tunnel testing equipment, characterized in that, The thermal protection specimen includes a thermal protection specimen back plate and a heat-insulating layer disposed on the back of the thermal protection specimen back plate; wherein, a heat-blocking layer is provided in the middle of the thermal protection specimen back plate, the heat-blocking layer dividing the thermal protection specimen back plate into a central region and an outer frame region, the central region being the micro-wind tunnel thermal protection test area; the size of the heat-blocking layer is consistent with the range of the uniform flow field of the micro-wind tunnel test; the heat-blocking layer is an annular heat-blocking layer with the center of the thermal protection specimen back plate as the center; the annular heat-blocking layer consists of multiple blocking through holes arranged in a ring on the thermal protection specimen back plate with the center of the thermal protection specimen back plate as the center.

2. The thermal protection specimen suitable for micro wind tunnel testing equipment according to claim 1, characterized in that, The heat-blocking layer only divides the back plate of the heat protection specimen.

3. The thermal protection specimen suitable for micro wind tunnel testing equipment according to claim 1, characterized in that, The heat-blocking layer is a square heat-blocking layer set with the center of the back plate of the heat protection specimen as the center.

4. The thermal protection specimen suitable for micro wind tunnel testing equipment according to claim 1, characterized in that, The blocking through-hole is only installed through the back plate of the thermal protection specimen.

5. A thermal protection specimen suitable for micro wind tunnel testing equipment according to claim 1, characterized in that, The annular heat-blocking layer is a blocking ring with the center of the back plate of the heat protection specimen as the center. The blocking ring divides the back plate of the heat protection specimen into a central area and an outer frame area.

6. A thermal protection specimen suitable for micro wind tunnel testing equipment according to claim 5, characterized in that, The blocking ring is filled with heat-insulating material.

7. A thermal protection specimen suitable for micro-wind tunnel testing equipment according to claim 6, characterized in that, The insulation material is a material with low thermal conductivity.

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