Ablation gas-phase product sampling device for heat-proof material flat plate model

Abstract

The invention provides an ablative gas-phase product sampling device for a heat-proof material flat plate model, and relates to the technical field of aircraft ground assessment tests. The flat plate model is installed in the tool, upstream airflow is used for heating the flat plate model, the flat plate model is heated to be ablated, and an ablated gas phase product is released; a cooling water channel is formed in the tool, so that the tool can work for a long time in a pneumatic thermal environment; the stop block is connected to the downstream side of the tool and used for limiting displacement of the flat plate model in the airflow direction. The sampler is installed in the check block and used for collecting ablated gas phase products released after the flat plate model is heated. The device can adapt to a severe test environment brought by high-temperature supersonic airflow, in-situ sampling of ablated gas phase products under the vacuum condition is achieved, and meanwhile the sampling process and the ablating process do not interfere with each other.

Description

Technical Field

[0001] This invention relates to the field of aircraft ground testing technology, and in particular to a sampling device for ablation gas phase products of a heat-resistant material plate model. Background Technology

[0002] Aerothermal ablation tests of the ground using electric arc wind tunnels are a primary method for screening heat-resistant materials or evaluating heat-resistant solutions. Compared to small-scale laboratory tests such as thermogravimetric analysis (TGA) and tubular furnace tests, electric arc wind tunnel tests can provide a more realistic aerothermal environment, and the experimental data obtained are more valuable for practical applications.

[0003] However, due to the complex aerodynamic and thermodynamic environment of electric arc wind tunnels, common laboratory analytical methods such as mass spectrometry, chromatography, and spectroscopy cannot be simply coupled into electric arc wind tunnel test systems. Adaptive design of the relevant equipment is required. For contact-type analytical methods such as mass spectrometry and chromatography, it is necessary to collect and transport the ablation gaseous products into the detection instrument. To achieve this, the sampling device should be capable of operating under aerodynamic and thermodynamic loads for extended periods; the sampling device should not affect the flow field or the ablation process of the heat-resistant material; and the sampling device should be able to perform sampling under vacuum conditions, in dusty, high-temperature, and high-speed gas flows, while ensuring sample validity.

[0004] In summary, for mass spectrometry and chromatographic analysis, sampling gaseous ablation products and analyzing their composition and content can provide a deeper understanding of the ablation behavior and mechanism of heat-resistant materials, thus supporting the research and development of heat-resistant materials.

[0005] In view of the above reasons, the present invention provides an in-situ sampling device for ablation gas phase products of heat-resistant material plate models, which can work for a long time in the aerodynamic and thermodynamic environment of electric arc wind tunnel, without affecting the supersonic flow field and the model ablation process. Summary of the Invention

[0006] The purpose of this invention is to provide a sampling device for ablation gas phase products of a heat-resistant material plate model. This sampling device can adapt to the harsh test environment brought about by high temperature supersonic airflow, realize in-situ sampling of ablation gas under vacuum conditions, and ensure that the sampling process and the ablation process do not interfere with each other.

[0007] This invention provides a sampling device for ablation gaseous products of a heat-resistant material plate model, comprising: a fixture and a plate model, the plate model being installed within the fixture, the fixture having a cooling water channel; a baffle connected to the downstream side of the fixture along the airflow direction to limit the displacement of the plate model along the airflow direction; and a sampler installed within the baffle to collect ablation gaseous products released after the plate model is heated; the plate model is heated by an upstream airflow to induce ablation, and the ablation gaseous products released after heating are collected by the sampler located downstream of the airflow.

[0008] Preferably, the tooling is a U-shaped structure with openings at the top, bottom, and one side. The top opening of the tooling has an inward stepped inner edge. The flat plate model has a stepped outer edge. The flat plate model is installed at the top opening of the tooling in the direction of airflow, and the stepped outer edge of the flat plate model is fitted with the stepped inner edge of the tooling.

[0009] Preferably, it also includes a cover plate that extends into the tooling and abuts against the back side of the flat plate model.

[0010] Preferably, the side of the stop block is provided with a through-hole, and the screw passes through the through-hole to engage with the screw hole on the side wall of the tooling.

[0011] Preferably, the cooling water channel of the tooling is opened inside the side wall of the tooling and adjacent to the upper surface of the tooling; the side wall of the tooling has an inlet and outlet that communicate with the cooling water channel.

[0012] Preferably, the block has a chamber for installing the sampler, the sampler is inserted into the chamber from the bottom of the block and its sampling port is connected to the top of the block.

[0013] Preferably, a cooling water channel is provided between the sampler and the chamber of the baffle, forming a partition-type water-cooled structure; a cooling water channel is provided inside the baffle, and the bottom of the baffle has an inlet and outlet that connect to the cooling water channel. After the cooling water enters the cooling water channel from the inlet on one side of the bottom of the baffle, it passes laterally through the chamber used to install the sampler, and leaves the cooling water channel from the outlet on the other side of the bottom of the baffle.

[0014] Preferably, the chamber is composed of multiple concentric circular holes with gradually increasing diameter from top to bottom, and the sampler is composed of multiple concentric cylindrical segments with gradually increasing diameter from top to bottom. The sampler is installed in the chamber from bottom to top.

[0015] Preferably, the sampler has a pressure block pressed against its bottom, and the pressure block is detachably connected to the bottom of the stop block.

[0016] Preferably, the sampler is made of a metal with high thermal conductivity, the top of the sampler is provided with micropores, and the sampler is provided with a sampling channel that runs through it.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. The sampling device in this invention can adapt to the harsh test environment brought about by high temperature and supersonic airflow. The plate model is positioned by tooling, and then the high temperature and high speed airflow upstream is used to heat the plate model, causing it to heat up and ablate. The sampler is fixed by a baffle and can collect the ablation gas phase products released after the plate model is heated, realizing in-situ sampling of ablation gas under vacuum conditions. At the same time, the sampling process and the ablation process do not interfere with each other. Moreover, the water-cooled sampling device can work for a long time in aerodynamic and thermodynamic environment.

[0018] 2. In this invention, the flat plate model and the tooling are sealed through stepped inner and outer edge gaps, with stops and cover plates providing positioning and clamping, thus achieving the installation of the flat plate model. This method avoids the use of high-temperature pyrolytic materials such as sealants, preventing the pyrolysis products of sealants from contaminating the heat-resistant material and ablating the gaseous products.

[0019] 3. The sampler, stop, and tooling in this invention adopt a split design, which makes it easy to replace and repair the components. The installation positions of the stop and tooling can be easily adjusted, ensuring that the supersonic flow field is not disturbed even when the ablation amount of the flat plate model is large. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is an explosion schematic diagram of the ablation gas phase product sampling device of the present invention; Figure 2 This is a schematic diagram of the internal structure of the stop block of the present invention; Figure 3 This is a schematic diagram of the internal structure of the sampler of the present invention; Explanation of reference numerals in the attached figures: 1: Tooling; 2: Flat plate model; 3: Stop block; 4: Sampler; 5: Pressure block; 6: Cover plate. Detailed Implementation

[0022] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] like Figure 1 As shown, this invention provides a sampling device for ablation gas phase products of a heat-resistant material plate model, comprising: tooling 1, plate model 2, baffle 3, sampler 4, pressure block 5, and cover plate 6. An electric arc heater heats the gas medium filled inside, forming a high-temperature gas flow. After processes such as mixing of hot and cold gases, pressure stabilization, and acceleration, a test flow field meeting the experimental requirements is formed.

[0026] Example 1 The flat plate model 2 is installed in the fixture 1, which has a cooling water channel. The baffle 3 is connected to the downstream side of the fixture 1 along the airflow direction to limit the displacement of the flat plate model 2 along the airflow direction. The sampler 4 is installed in the baffle 3 to collect the ablation gas phase products released after the flat plate model 2 is heated. The flat plate model 2 is heated by the upstream airflow to cause it to ablate. The ablation gas phase products released after the flat plate model 2 is heated are collected by the sampler 4 located downstream of the airflow.

[0027] Specifically, the dimensions of the plate model 2 are L1×L2, where L1=50~400mm and L2=50~400mm. The plate model 2 is installed on the top of the fixture 1 along with the high-temperature and high-speed airflow. The upstream high-temperature and high-speed airflow heats the plate model 2, causing it to ablate. The resulting ablation gaseous products are collected by the sampler 4 located in the downstream baffle 3.

[0028] In addition, during the process of ablation of the flat plate model 2, flowing cooling water is introduced into the side wall of tooling 1 through the inlet and outlet on both sides of tooling 1, which can cool tooling 1 and thus effectively improve the device's ability to work for a long time in the aerodynamic and thermal environment of the electric arc wind tunnel.

[0029] Example 2 This embodiment 2 describes in detail the installation and fixing method of the flat plate model 2.

[0030] The fixture 1 is a U-shaped structure with openings at the top, bottom, and one side, and the top opening of the fixture 1 has an inwardly stepped inner edge. The flat plate model 2 (except for the front side to be abutted by the stop block) has stepped outer edges on three sides, and the flat plate model 2 is installed at the top opening of the fixture 1 in the direction of airflow, with the stepped outer edge of the flat plate model 2 fitting into the stepped inner edge of the fixture 1. It also includes a cover plate 6, which extends into the fixture 1 and abuts against the back side of the flat plate model 2. The stop block 3 has a through-hole on its side, and screws pass through the through-hole to engage with screw holes on the side wall of the U-shaped opening of the fixture 1 for detachable connection.

[0031] Specifically, the stepped inner edge of the top opening slot of fixture 1 matches and nests with the stepped outer edge of the flat plate model 2, allowing the flat plate model 2 to slide into fixture 1 when it is installed. The projection of the cover plate 6 perpendicular to the high-temperature, high-speed airflow direction is U-shaped, with its inner contour extending upwards into a square tube shape to abut against the bottom of the flat plate model 2. The four corners of the end face of the cover plate 6 are connected to the bottom of fixture 1 by screws. The stop block 3 restricts the displacement of the flat plate model 2 along the airflow direction, and its side oblong hole allows for height adjustment of the stop block 3 relative to fixture 1. For example, when the flat plate model 2 is ablated to a certain thickness, the position of the stop block can be adjusted downwards through the oblong hole to prevent the stop block from affecting the airflow.

[0032] After the flat plate model 2 is inserted into the fixture 1, the cover plate 6 is pushed upwards from the bottom opening of the fixture 1 and fixed to the fixture 1 with screws. This causes the top of the cover plate 6 to press against the bottom of the flat plate model 2 (i.e., the flat plate model 2 is sandwiched between the stepped outer edge of the fixture 1 and the cover plate 6), thus leveling the flat plate model 2 and limiting its displacement in the vertical airflow direction. Then, the stop block 3 is connected to the downstream side of the fixture 1 to further limit the displacement of the flat plate model 2 along the airflow direction.

[0033] It should also be noted that in the existing technology, the installation of flat plate models currently uses sealant, which will pyrolyze and produce gas when heated, affecting mass spectrometry analysis; while the present invention achieves sealing by interlocking the stepped inner edge of the top opening of the tooling 1 with the stepped outer edge of the flat plate model 2 to form a gap seal, thus avoiding the adverse effects of sealant and other materials.

[0034] Example 3 This embodiment 3 specifically describes the structure of the cooling water channel of tooling 1.

[0035] The cooling water channel of tooling 1 is opened inside the side wall of tooling 1 and adjacent to the upper surface of tooling 1; there are inlet and outlet water ports on the outside of the side wall of tooling 1 that connect to the cooling water channel.

[0036] Specifically, fixture 1 is an extension of one sidewall of the upstream gas flow channel. Fixture 1 is made of a highly thermally conductive metal with a thermal conductivity greater than 50 W / m·K. The cooling water channel is a cavity structure machined into the three sidewalls forming fixture 1. When cooling water enters from one inlet, it flows along the three sidewalls in a U-shaped trajectory and exits from the outlet on the opposite side. The height of the cooling water channel is adjacent to the upper surface of fixture 1, because this location is close to the high-temperature, high-heat gas flow. The cooling water channel uses high-pressure cooling water with a pressure of 1~5 MPa, enabling fixture 1 to maintain a residence time t1 ≥ 3000 s in a pneumatically heated environment.

[0037] Example 4 This embodiment 4 specifically describes the sampler 4 and its installation method, as well as the structure of the cooling water channel of the block 3.

[0038] The stopper 3 has a chamber for installing the sampler 4. The sampler 4 is inserted into the chamber from the bottom of the stopper 3, and its sampling port penetrates through the top end of the stopper 3. A cooling water channel is provided between the sampler 4 and the chamber of the stopper 3, forming a partition-type water-cooled structure. The stopper 3 is provided with a cooling water channel, and the bottom of the stopper 3 has water inlets and outlets communicating with the cooling water channel. After the cooling water enters from the water inlet on one side of the bottom of the stopper 3, it laterally passes through the chamber for installing the sampler 4 and leaves the cooling water channel from the water outlet on the other side of the bottom of the stopper 3. The chamber consists of multiple concentric circular holes with diameters gradually increasing from top to bottom, and the sampler 4 consists of multiple concentric cylindrical segments with diameters gradually increasing from top to bottom. The sampler 4 is installed in the chamber from bottom to top. A pressing block 5 is pressed against the bottom of the sampler 4, and the pressing block 5 is detachably connected to the bottom of the stopper 3.

[0039] Specifically, the sampler 4 is inserted into the stopper 3, and its top end is flush with the stopper 3, for collecting the ablated gas-phase products released after the flat plate model 2 is heated. After the sampler 4 is installed into the stopper 3, the pressing block 5 is detachably connected to the bottom of the stopper 3 by screws to press the bottom of the sampler 4, which can prevent the cooling water from extruding the sampler 4. The sampler 4 and the stopper 3 are sealed by a sealing ring to prevent the cooling water from overflowing and affecting the sampling process.

[0040] As Figure 2 shown, the stopper 3 is made of a metal with high thermal conductivity, its thermal conductivity coefficient is greater than 50 W / m·K, and its interior is provided with a cooling water channel, which can cool the upper surface in contact with the high-temperature and high-pressure gas flow. The cooling water channel in the stopper 3 is in an inverted U-shaped structure, as Figure 2 shown in the figure, the water inlet is located on the right side of the bottom of the stopper 3 and between the right waist-shaped hole and the right screw hole for fixing the pressing block 5, and the water outlet is located on the left side of the bottom of the stopper 3 and between the left waist-shaped hole and the left screw hole for fixing the pressing block 5. After the cooling water enters, it first flows upward to near the upper surface of the stopper 3, then laterally passes through the chamber, and then flows downward and out from the water outlet. It should be noted that Figure 1 the water inlets and outlets of the cooling water channel in the stopper 3 are not shown in the figure, Figure 1 and the holes on the side in the figure are process holes for manufacturing the cooling water channel.

[0041] Multiple concentric circular holes with diameters gradually increasing from top to bottom are arranged perpendicular to the gas flow direction in the stopper 3. The diameters from the end close to the flat plate model 2 to the end far from it are D1, D2, D3, and D4 respectively, and D1 < D2 < D3 < D4 is satisfied. Waist-shaped holes perpendicular to the axis direction of the concentric circular holes are arranged on both sides of the concentric circular holes, and the width of the waist-shaped holes is 5 mm to 15 mm. The baffle 3 and the tooling 1 are connected by screws. For the flat plate model with a large ablation amount, the connection position between the stopper 3 and the tooling 1 can be adjusted through the waist-shaped holes.

[0042] AsAs shown in Figure 3 , the sampler 4 is made of a metal with high thermal conductivity, whose thermal conductivity is greater than 50 W / m·K. It consists of multiple concentric cylindrical segments with diameters gradually increasing from top to bottom, with diameters D5, D6, and D7 respectively, satisfying D5 < D6 < D7. Sealing ring grooves are arranged on the outer periphery of the cylindrical segments with diameters D6 and D7. The sampler 4 is matched with a chamber composed of multiple concentric circular holes with diameters gradually increasing from top to bottom, and is inserted and installed from bottom to top, so that the upper part of the sampler 4 is limited by the diameter of the chamber and cannot move axially, and the lower part is pressed by the pressing block 5, thus realizing the stable installation and use of the sampler 4. Micropores are arranged at the top of the sampler 4, and the pore diameter of the micropores is 0.1 mm to 3 mm. A sampling channel penetrating through it is arranged inside the sampler 4, and the inner diameter of the sampling channel is 1 mm to 5 mm. The micropores and the sampling channel together constitute a gas channel. A partition type water cooling structure is formed between the sampler 4 and the stop block 3, D3 - D6 > 1 mm, and its outside is cooled by high-pressure water, and the cooling water pressure is 1 to 5 MPa. The tail of the sampler 4 is connected to a gas transmission pipeline, and after transmission, it enters the backend analytical instrument to analyze the ablation gas-phase products.

[0043] 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 foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.​

Claims

1. A sampling device for ablation vapor products of a heat-resistant material plate model, characterized in that, include: Tooling (1) and flat plate model (2), wherein the flat plate model (2) is installed in the tooling (1), and the tooling (1) is provided with a cooling water channel; A stop (3) is connected to the downstream side of the tooling (1) along the airflow direction to limit the displacement of the flat plate model (2) along the airflow direction. Sampler (4), which is installed inside the baffle (3), is used to collect the ablation gaseous products released after the plate model (2) is heated; The plate model (2) is heated by the upstream airflow to cause it to ablate. The ablation gaseous products released by the plate model (2) after heating are collected by the sampler (4) located downstream of the airflow.

2. The ablation vapor product sampling device for a heat-resistant material plate model according to claim 1, characterized in that, The tooling (1) is a U-shaped structure with openings at the top, bottom and one side, and the top opening of the tooling (1) has an inward stepped inner edge; The flat plate model (2) has a stepped outer edge; The flat plate model (2) is installed at the top opening of the tooling (1) in the direction of airflow, and the stepped outer edge of the flat plate model (2) is fitted with the stepped inner edge of the tooling (1).

3. The ablation vapor product sampling device for a heat-resistant material plate model according to claim 1, characterized in that, It also includes a cover plate (6) that extends into the tooling (1) and abuts against the back of the flat plate model (2).

4. The ablation vapor product sampling device for a heat-resistant material plate model according to claim 1, characterized in that, The side of the stop block (3) is provided with a waist-shaped hole that passes through it, and the screw passes through the waist-shaped hole and is connected to the screw hole on the side wall of the tooling (1).

5. The ablation vapor product sampling device for a heat-resistant material plate model according to claim 1, characterized in that, The cooling water channel of the tooling (1) is opened inside the side wall of the tooling (1) and adjacent to the upper surface of the tooling (1); the side wall of the tooling (1) has an inlet and outlet that connect to the cooling water channel.

6. The ablation vapor product sampling device for a heat-resistant material plate model according to claim 1, characterized in that, The block (3) has a chamber for installing the sampler (4), and the sampler (4) is inserted into the chamber from the bottom of the block (3) and its sampling port is connected to the top of the block (3).

7. The ablation vapor product sampling device for a heat-resistant material plate model according to claim 6, characterized in that, A cooling water channel is provided between the sampler (4) and the chamber of the baffle (3), forming a partition-type water-cooled structure; The block (3) has a cooling water channel. The bottom of the block (3) has an inlet and outlet that connect to the cooling water channel. After the cooling water enters the cooling water channel from the inlet on one side of the bottom of the block (3), it passes laterally through the chamber used to install the sampler (4) and leaves the cooling water channel from the outlet on the other side of the bottom of the block (3).

8. The ablation vapor product sampling device for a heat-resistant material plate model according to claim 6, characterized in that, The chamber is composed of multiple concentric circular holes with gradually increasing diameter from top to bottom, and the sampler (4) is composed of multiple concentric cylindrical segments with gradually increasing diameter from top to bottom. The sampler (4) is installed in the chamber from bottom to top.

9. The ablation vapor product sampling device for a heat-resistant material plate model according to claim 6, characterized in that, The sampler (4) has a pressure block (5) pressed against its bottom, and the pressure block (5) is detachably connected to the bottom of the stop block (3).

10. The ablation vapor product sampling device for a heat-resistant material plate model according to claim 1, characterized in that, The sampler (4) is made of a metal with high thermal conductivity. Micropores are arranged on the top of the sampler (4), and a sampling channel is provided inside the sampler (4).

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