Sweat cooling type high-temperature water-cooling double-hole dynamic pressure probe for measuring subsonic three-dimensional flow field

Abstract

The utility model belongs to the technical field of high-temperature flow field testing, and particularly relates to a sweating cooling type high-temperature water-cooling double-hole dynamic pressure probe for measuring a subsonic three-dimensional flow field. The device is composed of a probe supporting rod, a probe head, a sleeve, a mounting seat, a positioning hole, a cooling water inlet pipe, a cooling water outlet pipe, a cable, a diverging wall surface, an impact wall surface, a current limiting wall surface, a circumferential separation baffle plate, a dynamic pressure sensor and the like. Cooling water enters the probe through the water inlet pipe, after the probe head is subjected to impact cooling, one part of the cooling water permeates to the surface of the diverging wall face in the radial direction to sweate and cool the probe, and the other part of the non-permeated part flows out of the probe in the axial direction after being heated through convection heat exchange. The cylindrical surface and the diagonal plane of the probe head are respectively provided with a pressure measuring hole, so that three-dimensional flow field measurement can be realized. The probe has the advantages that the probe cooling efficiency is greatly improved by adopting sweating cooling, the probe head is also cooled, the service life of the probe in an extreme high-temperature environment (the highest temperature reaches 2500 DEG C) is prolonged, and the reliability of a measurement result is improved.

Description

Technical Field

[0001] This invention belongs to the technical field of high-temperature flow field dynamic pressure testing, specifically a transpiration-cooled, high-temperature, water-cooled, dual-aperture dynamic pressure probe for measuring subsonic three-dimensional flow fields. This probe is suitable for measuring three-dimensional flow parameters such as total pressure, static pressure, Mach number, deflection angle, and pitch angle in highly unsteady subsonic three-dimensional flow fields at extreme high temperatures, such as those at the turbine rotor outlet of an aircraft engine. The invention utilizes a composite structure combining transpiration cooling and impingement cooling to achieve efficient cooling of both the probe support and probe head, ensuring reliable operation in extreme high-temperature environments up to 2500°C. Background Art

[0002] With the rapid development of aerospace technology, the operating environment of aircraft engines has become extremely harsh. In particular, the temperatures of components such as the combustion chamber and turbine continue to rise, reaching extremely high levels (up to 2300°C). Furthermore, due to the high-speed rotation of the turbine rotor, the rotor outlet flow field is highly unsteady, making it impossible to obtain the dynamic distribution of the rotor outlet flow field using conventional steady-state pressure probes.

[0003] Measuring pressure in high-temperature, highly unsteady flow fields, such as those at turbine rotor outlets, presents numerous challenges. A key challenge is ensuring that the pressure probe possesses sufficient strength and reliability in harsh environments, requiring an effective cooling structure and sufficient accuracy. Currently, two primary cooling methods exist for pressure probes operating in high-temperature environments: film cooling and water cooling. While each has its advantages, they also present technical drawbacks that impact the performance and service life of the probe.

[0004] The advantage of film cooling is that the temperature and flow of the cooling airflow can be easily adjusted according to the mainstream temperature and flow rate. However, this structure has certain drawbacks in cooling the probe head: if film holes are opened in the probe head, the cooling airflow rushing out will interfere with the flow field of the probe head, affecting the test accuracy. If the leading edge of the probe support rod does not have film holes, and the probe relies solely on internal convection heat transfer for cooling, due to the small specific heat capacity of the gas, the cooling effect of film cooling in extremely high ambient temperatures (above 2000°C) is limited, which may cause damage to the probe.

[0005] The advantage of a water-cooled probe is that the flow of cooling water will not interfere with the flow field, and since the specific heat capacity of water is much greater than that of air, the cooling effect is better. However, the complexity of the water-cooling system increases the difficulty of designing and maintaining water-cooled probes. The cooling water flow rate is difficult to adjust quickly when the test state changes, which may cause the local temperature of the probe to be too high or the pressure to be too high, increasing the risk of structural damage. At the same time, most existing water-cooled probes use convective heat exchange between the probe and the cooling water to cool the probe, and do not cool the probe head. This type of heat exchange process is a sensible heat exchange process. When the measurement environment temperature rises, the required cooling water flow rate increases greatly. If the design of the cooling water flow channel in the probe is unreasonable, there will be problems such as large internal resistance, insufficient contact between the cooling water and the probe support rod, and dead water areas, resulting in unsatisfactory cooling effect. Moreover, due to the small size of the probe, the operation of the water-cooled probe is more difficult.

[0006] Compared to sensible heat transfer, which reduces probe temperature through convection, latent heat transfer, which absorbs large amounts of heat through phase changes (such as from liquid to gas or solid to liquid), offers more efficient cooling. Under the same conditions, latent heat transfer can transfer much more heat than sensible heat transfer. Transpiration cooling is a common cooling method that utilizes latent heat transfer, and its use can, to a certain extent, reduce the cooling water flow requirements for probes in extremely high-temperature environments.

[0007] Another major challenge is accurately measuring dynamic flow parameters under highly unsteady conditions. In components like combustion chambers and turbines, and even in variable-cycle engines, high-temperature airflow is often highly three-dimensional and unsteady, with dramatic variations in flow direction and velocity vectors, necessitating the use of dynamic probes for measurement. To ensure a high frequency response in dynamic pressure probes, in addition to employing high-frequency sensors, the distance between the pressure tap and sensor must be minimized, effectively minimizing the probe's cavity effect.

[0008] Due to the weak high-temperature resistance of pressure sensors, when measuring flow field parameters in extremely high-temperature environments, existing probes often prioritize maintaining the temperature of the sensor's location after comprehensively considering the probe size, the sensor's high-temperature resistance, and the ambient temperature. This forces the sensor to be placed in a location within the probe support rod for better cooling, which often results in a larger cavity effect between the sensor and the pressure measuring hole. In theory, if a sufficiently effective cooling method is used to effectively thermally protect the sensor, the distance between the sensor and the pressure measuring hole can be shortened as much as possible, reducing the impact of the cavity effect and allowing the probe's dynamic response capability to be as close to the sensor's own frequency response as possible, thereby helping researchers obtain more complete signals, improving their comprehensive understanding of the flow field, and optimizing design.

[0009] The invention patent with publication number CN106885682A proposes a cylindrical double-hole pressure probe for measuring the subsonic three-dimensional flow at the rotor outlet, but the probe is not cooled and is not suitable for high-temperature environments. The two invention patents with publication numbers CN107063560A and CN107131999A respectively propose a high-temperature water-cooled dynamic pressure probe and a high-temperature water-cooled steady-state pressure probe; the utility model patent with publication number CN206930646U proposes a water-cooled probe. The above-mentioned water-cooled probes all use the sensible heat exchange process of cooling water absorbing the heat of the probe support rod to cool the probe support rod. The cooling effect they can provide in extremely high-temperature environments is limited, which may affect the accuracy of the probe measurement data and even cause damage to the probe. More importantly, the above-mentioned water-cooled probes do not cool the probe head, so the risk of the probe head being damaged by high temperature is relatively high.

[0010] Therefore, there is an urgent need to develop a dynamic pressure probe that has a good cooling effect on both the probe support rod and the probe head, can work stably and reliably in extreme high temperature environments (above 2000°C), and is less affected by the cavity effect, so as to meet the testing requirements of the dynamic three-dimensional flow field parameters at the rotor outlet of high-temperature rotating components such as turbines. Summary of the Invention

[0011] The present invention's omnidirectional high-temperature water-cooled dynamic pressure probe, capable of stable operation at extremely high temperatures, employs a composite structure to achieve the "sweating" function of cooling water on the probe surface. The cooling water seeps through micropores on the probe surface and evaporates on the surface, removing a large amount of heat. This type of heat exchange is a latent heat exchange process. During this heat exchange process, the latent heat transfer amount is calculated as follows:

[0012] in, In the above formula, Q evap is the latent heat transferred by evaporative cooling L v is the latent heat of vaporization of water (about 2.26×10 6 J / Kg), is the rate of evaporation of the liquid, P sat is the saturated water vapor pressure on the liquid surface, P is the water vapor pressure of the environment, R is the gas constant (for water vapor, it is approximately 461.5 J / (kg·K), A evap is the evaporation area.

[0013] In the process of convective heat transfer, the calculation relationship of sensible heat transfer is:

[0014] Q conv =h·A conv ΔT

[0015] In the above formula, Q convis the sensible heat transferred by convection, ΔT is the temperature difference, and A conv is the heat transfer area, and h is the convective heat transfer coefficient. In the water-cooled probe, water flows turbulently in the stainless steel pipe. The convective heat transfer coefficient h is estimated to be approximately 160.37W / (m 2 ·K).

[0016] Based on the above analysis, it is obvious that under the same conditions, the heat absorbed by the sweat cooling (evaporative cooling) process is much greater than the cold absorbed by the convection heat transfer process. The use of sweat cooling can not only effectively reduce the surface temperature of the material, but also form a protective cooling layer to prevent the high-temperature airflow from directly contacting the material surface, thereby greatly improving the high-temperature resistance of the material. The sweat cooling technology has the following advantages:

[0017] 1. Efficient cooling: absorbs heat through liquid evaporation, significantly reducing the surface temperature of the material.

[0018] 2. Thermal protection: Form a coolant layer to block the direct thermal impact of high-temperature airflow on the material.

[0019] 3. Adaptability: Automatically adjust the coolant seepage according to changes in ambient temperature to achieve adaptive cooling.

[0020] The present invention provides a transpiration-cooled high-temperature water-cooled double-hole dynamic pressure probe for measuring subsonic three-dimensional flow fields. The technical problems to be solved are: first, to solve the problem that existing pressure probes are difficult to operate stably and measure reliably in environments with extremely high temperatures (above 2000°C) and strong non-stationary conditions, such as the rotor outlet of rotating components such as turbines. Second, to solve the problem that the dynamic pressure sensor in the existing dynamic pressure probe has a large cavity effect and a low frequency response in a high-temperature environment. Third, to solve the problem that the internal cooling water flow rate of existing water-cooled probes is difficult to adjust quickly, and may boil in the probe to produce bubbles that block the flow channel.

[0021] The technical solution of the present invention is:

[0022] A transpiring cooling type high-temperature water-cooled double-hole dynamic pressure probe for measuring subsonic three-dimensional flow fields, comprising a probe support rod (1), a probe head (2), a sleeve (3), a mounting seat (4), a positioning hole (5), a cooling water inlet pipe (6), a cooling water outlet pipe (7), a cable (8), a circumferential partition baffle (9), a first wall surface—a diverging wall surface (10), a second wall surface—an impact wall surface (11), a third wall surface—a flow limiting wall surface (12), a fourth wall surface—an outer wall surface of the probe support rod (13), a dynamic pressure sensor (18), and a flow column (14), a diverging hole (15), an impact hole (16), and a flow limiting hole (17); The invention is characterized in that: the probe head (2) is located at the front end of the probe support rod (1), the probe head (2) includes a common bottom surface cylinder and a hemispherical beveled body part, and two dynamic pressure sensors (18) are independently packaged inside the probe head; the sleeve (3) is installed on the outside of the probe support rod (1), the mounting seat (4) is installed on the sleeve (3), and the mounting seat (4) is provided with a positioning hole (5); the cooling water inlet pipe (6) and the cable (8) are both installed in the probe support rod (1); the cooling water outlet pipe (7) is installed on the sleeve (3) and behind the mounting seat (4); the cable (8) is installed in the probe support rod (1) and is arranged circumferentially on the periphery of the cooling water inlet pipe (6).

[0023] Furthermore, the probe support rod (1) has a double-layer structure, the inner layer is connected to the cooling water inlet pipe (6) as a cooling water inlet channel, and the outer layer is divided into six chambers by a circumferential partition baffle (9), and two dynamic pressure sensors (18) and corresponding cables (8) are respectively placed on the front and rear sides. Each chamber and the third cooling channel together serve as a cooling water circuit.

[0024] Furthermore, the outer diameter of the probe support rod (1) is 2 mm to 5 mm, and the outer diameter of the corresponding sleeve (3) is 4 mm to 10 mm. The two are welded into a whole, and the diameter of the cooling water inlet pipe (6) is 1 mm to 2 mm.

[0025] Furthermore, the probe head (2) is a cylindrical portion whose axial length from the probe top to the end face is three times the outer diameter of the probe support rod (1). The probe head (2) is composed of a cylindrical end portion and a hemispherical beveled body with a common bottom surface. The diameter of the beveled body is the same as the diameter of the outer wall of the sleeve, and the angle between the beveled surface and the horizontal plane is 30° to 60°.

[0026] Furthermore, a No. 1 pressure measuring hole (21) is opened on the cylindrical surface of the probe head (2), and a No. 2 pressure measuring hole (22) is opened on the oblique surface of the hemispherical bevel body, and the No. 2 pressure measuring hole (22) is located directly below the No. 1 pressure measuring hole (21), and the vertical distance between the centers of the two pressure measuring holes is 3 mm to 10 mm. The two pressure measuring holes of the probe head (2) are respectively connected to the two dynamic pressure sensors (18) and the signals are led out of the probe through the cable (8), wherein the No. 1 pressure measuring hole (21) corresponds to the No. 1 pressure sensor (181) and the No. 1 cable (81), and the No. 2 pressure measuring hole (22) corresponds to the No. 2 pressure sensor (182) and the No. 2 cable (82), and the diameter of the pressure measuring holes is 0.6 mm to 1.5 mm.

[0027] Furthermore, on the probe head (2), no diffuse holes (15) are developed within a range of three times the diameter of the pressure measuring hole No. 1 on the cylindrical surface of the pressure measuring hole (21), and no diffuse holes are developed on the oblique surface where the pressure measuring hole No. 2 (22) is located, so as to avoid interference of the pressure measuring holes with the steam generated by evaporative cooling. The diffuse holes (15) are developed on the remaining surfaces, and the probe head (2) is cooled by sweat cooling of the hemispherical surface of the hemispherical oblique cut body and impact cooling generated by the cooling water inlet pipe (6).

[0028] Furthermore, the sleeve (3) is a three-layer structure, comprising a first wall surface—a diverging wall surface (10), a second wall surface—an impact wall surface (11), and a third wall surface—a flow-limiting wall surface (12); a first cooling channel is formed between the first wall surface—the diverging wall surface (10), the second wall surface—the impact wall surface (11), and the second wall surface—the impact wall surface (11); a second cooling channel is formed between the second wall surface—the impact wall surface (11), the second wall surface—the impact wall surface (11), and the third wall surface—the flow-limiting wall surface (12); and a third cooling channel is formed between the third wall surface and the outer wall surface (13) of the probe support rod. The above three cooling channels are cooling water infiltration channels.

[0029] Furthermore, the mounting seat (4) is in a runway shape, the thickness of the mounting seat (4) is 2 mm to 5 mm, and the mounting seat (4) is provided with two or more positioning holes (5) suitable for other specific measurement occasions, and the diameter of the positioning hole (5) is 2 mm to 3 mm.

[0030] Furthermore, six circumferential partition baffles (9) are evenly arranged circumferentially between the outer wall of the cooling water inlet pipe (6) and the first wall—the diverging wall (10) to reduce the negative influence of gravity on the uneven distribution of cooling water. The circumferential partition baffles penetrate the second wall—the impact wall (11), the second wall—the impact wall (11), the third wall—the flow limiting wall (12), and the fourth wall—the outer wall of the probe support rod (13), thereby circumferentially dividing the first cooling channel, the second cooling channel, the third cooling channel, and the cooling water return channel into six independent cooling areas. The six cooling water return channels correspond to the six independent cooling areas one by one.

[0031] Furthermore, the cooling water outlet pipe (7) is connected to the cooling water main circuit, and the cooling water whose temperature in the probe rises to a certain level but fails to enter the third flow channel between the outer wall surface (13) of the probe support rod and the flow-limiting wall surface (12) is discharged in time, that is, the heat that cannot be completely absorbed by the sweating cooling process is further absorbed by the flowing cooling water through convective heat transfer, thereby better protecting the dynamic pressure sensor (18).

[0032] Furthermore, the surface of the first wall surface - the diverging wall surface (10) is provided with S-shaped cylindrical diverging holes (15), which are evenly distributed along the circumference and periodically staggered in the axial direction, forming a diverging wall surface (10) with evenly dense diverging holes. The diverging holes (15) penetrate the first wall surface - the diverging wall surface (10), and cooling water seeps out from the diverging holes to form a liquid film evaporation cooling outer wall surface of the sleeve (3).

[0033] Furthermore, the diverging hole (15) is an S-shaped cylindrical hole to prevent the cooling water from quickly overflowing and affecting the measurement accuracy when the water supply pressure is too high. The diameter of the diverging hole (15) is 0.05 mm to 0.15 mm, and the angles between the two inclined lines in the broken line axis and the radial and horizontal directions of the probe support rod are both between 30° and 60°.

[0034] Furthermore, the second wall surface—the impact wall surface (11) and the second wall surface—the impact wall surface (11) are evenly distributed with impact holes (16), and the impact holes (16) connect the first cooling channel and the second cooling channel. Cooling water passes through the second wall surface—the impact wall surface (11) and the second wall surface—the impact wall surface (11) from the second cooling channel into the first cooling channel, and performs impact cooling on the first wall surface—the divergent wall surface (10). The impact holes (16) are straight holes and are axially staggered and periodically distributed on the second wall surface—the impact wall surface (11). The diameter of the impact holes (16) is 0.1 mm to 0.3 mm.

[0035] Furthermore, a plurality of groups of flow-limiting holes (17) are evenly arranged on the surface of the third wall surface, the flow-limiting wall surface (12), in the circumferential direction. Since the thermal environments at different axial positions of the probe support rod (1) may be different, the required flow rates may also be different. Different numbers of flow-limiting holes (17) can be opened at different axial positions of the probe support rod (1) according to the thermal environment of the probe to control the flow of cooling water entering different positions, thereby controlling the cooling effect at different positions. The diameter of the flow-limiting holes (17) is 0.2 mm to 0.4 mm.

[0036] Furthermore, a spoiler column (14) is provided in the first cooling channel, which is evenly distributed in the circumferential direction and staggered periodically distributed in the axial direction to form a uniformly dense group of spoiler columns. The upper and lower end surfaces of the spoiler column (14) are fixedly connected to the first wall surface - the diverging wall surface (10) and the second wall surface - the impact wall surface (11) to enhance the overall heat exchange performance. The diameter of the spoiler column (14) is 0.1 mm to 0.2 mm.

[0037] Furthermore, the probe of the present invention can measure three-dimensional flow fields with a dual-hole probe. During actual measurement, pressure data at different deflection angles can be obtained by rotating the probe or performing multiple measurements. The deflection angle calibration curve of the probe is obtained by fitting the curve. At the same time, the pitch angle coefficient is defined as:

[0038]

[0039] In the above formula, C pp is the pitch angle coefficient, P1 is the pressure measured by the No. 1 pressure measuring hole (21), P2 is the pressure measured by the No. 2 pressure measuring hole (22), P 1,max+40 is the pressure measured when the No. 1 pressure measuring hole (21) is deflected 40° in the positive direction corresponding to the maximum pressure position, P 1,max-40 It is the pressure measured when the No. 1 pressure measuring hole (21) is deflected 40° in the opposite direction corresponding to the maximum pressure position.

[0040] The present invention provides a transpiration-cooled high-temperature water-cooled double-hole dynamic pressure probe for measuring subsonic three-dimensional flow fields, which has the following beneficial effects:

[0041] Beneficial Effect 1: The present invention can cool the probe support rod and probe head simultaneously, effectively increasing the probe's service life and upper operating temperature limit in high-temperature environments. The present invention proposes a transudation cooling structure suitable for a dual-hole pressure probe, which combines the advantages of convection heat transfer cooling and transudation cooling. The cooling water in the permeated part absorbs a large amount of heat through evaporation, and the non-permeated cooling water absorbs heat and heats up before flowing out through the outlet pipe to further cool the probe and dynamic pressure sensor. This structure can absorb a large amount of heat even when the probe is small in size and the cooling water flow is limited, effectively increasing the probe's service life and upper operating temperature limit (up to 2500°C) in high-temperature environments.

[0042] Beneficial Effect 2: Compared with other dynamic total pressure probes, the probe of the present invention has better dynamic response capability and measurement results. The probe head of the present invention adopts a hemispherical bevel, which can perform sweat cooling at the rear while avoiding interference with the pressure measuring hole. Combined with shock cooling, it can effectively prevent the local temperature of the probe head from being too high. Compared with other water-cooled probes, the dynamic pressure sensor of the present invention can be installed on the probe head closer to the pressure measuring hole, effectively reducing the cavity effect between the pressure measuring hole of the probe head and the dynamic pressure sensor, thereby improving the dynamic response capability of the probe in high temperature environments and effectively ensuring the accuracy of the probe measurement results.

[0043] Beneficial effect three: Compared with other high-temperature water-cooled dynamic porous pressure probes, the present invention only installs two dynamic pressure sensors on the head, which has the advantages of simple structure, small size and low cost, and has application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 The diagram is a schematic diagram of the overall structure of a transpiration-cooled high-temperature water-cooled double-hole dynamic pressure probe for measuring subsonic three-dimensional flow fields according to the present invention.

[0045] Figure 2 yes Figure 1 Enlarged front and side views of the probe head.

[0046] Figure 3 yes Figure 1 Top view and cross-sectional view of section AA.

[0047] Figure 4 yes Figure 2 The BB cross-sectional view of the probe head is shown, wherein the solid arrow indicates the axial flow direction of the cooling water, and the hollow arrow indicates the radial penetration direction of the cooling water.

[0048] Figure 5 It is a cross-sectional view of the S-shaped cylindrical diverging hole opened on the first wall - the diverging wall, where the arrow represents the direction of cooling water penetration and outflow.

[0049] Among them: 1-probe support rod, 2-probe head, 3-sleeve, 4-mounting seat, 5-positioning hole, 6-cooling water inlet pipe, 7-cooling water outlet pipe, 8-cable, 9-circumferential partition plate, 10-first wall - divergent wall, 11-second wall - impact wall, 12-third wall - flow limiting wall, 13-fourth wall - outer wall of probe support rod, 14-spoiler cylinder, 15-divergent hole, 16-impact hole, 17-flow limiting hole, 18-dynamic pressure sensor, 21-No. 1 pressure measuring hole, 22-No. 2 pressure measuring hole, 81-No. 1 cable, 82-No. 2 cable, 181-No. 1 dynamic pressure sensor, 182-No. 2 dynamic pressure sensor. DETAILED DESCRIPTION

[0050] The present invention is described in detail below with reference to the accompanying drawings and a specific implementation case, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more precise definition of the protection scope of the present invention.

[0051] See also Figures 1 to 5The present invention shows a transpiration-cooled high-temperature water-cooled double-hole dynamic pressure probe for measuring subsonic three-dimensional flow fields, comprising a probe support rod (1), a probe head (2), a sleeve (3), a mounting seat (4), a positioning hole (5), a cooling water inlet pipe (6), a cooling water outlet pipe (7), a cable (8), a circumferential partition baffle (9), a first wall surface—a diverging wall surface (10), a second wall surface—an impact wall surface (11), a third wall surface—a flow-limiting wall surface (12), a fourth wall surface—an outer wall surface of the probe support rod (13), a dynamic pressure sensor (18), and an interfering flow column (14), a diverging hole (15), an impact hole (16), a flow-limiting hole (17) ); characterized in that: the probe head (2) is located at the front end of the probe support rod (1), the probe head (2) includes a common bottom surface cylinder and a hemispherical beveled body part, and two dynamic pressure sensors (18) are independently packaged inside the probe support rod (1), the sleeve (3) is installed on the outside of the probe support rod (1), the mounting seat (4) is installed on the sleeve (3), and the mounting seat (4) is provided with a positioning hole (5), the cooling water inlet pipe (6) and the cable (8) are both installed in the probe support rod (1), the cooling water outlet pipe (7) is installed on the sleeve (3) and behind the mounting seat (4), and the cable (8) is installed in the probe support rod (1) and is arranged circumferentially on the periphery of the cooling water inlet pipe (6).

[0052] The probe support rod (1) has a double-layer structure, the inner layer is connected to the cooling water inlet pipe (6) as a cooling water inlet channel, and the outer layer is divided into six chambers by a circumferential partition baffle (9). Two dynamic pressure sensors (18) and corresponding cables (8) are respectively placed on the front and rear sides. Each chamber and the third cooling channel together serve as a cooling water circuit.

[0053] In this embodiment, the outer diameter of the probe support rod (1) is 3 mm, and the outer diameter of the corresponding sleeve (3) is 5 mm. The two are welded into a whole. The diameter of the cooling water inlet pipe (6) is 1.5 mm.

[0054] The probe head (2) is a cylindrical portion whose axial length from the probe top to the end face is three times the outer diameter of the probe support rod (1). The probe head (2) is composed of a cylindrical end portion and a hemispherical beveled body with a common bottom surface. The diameter of the beveled body is the same as the diameter of the outer wall of the sleeve (3). In this embodiment, the angle between the beveled surface and the horizontal plane is 40°.

[0055] A No. 1 pressure measuring hole (21) is opened on the cylindrical surface of the probe head (2), and a No. 2 pressure measuring hole (22) is opened on the oblique surface of the hemispherical beveled body, and the No. 2 pressure measuring hole (22) is located directly below the No. 1 pressure measuring hole (21). In this embodiment, the vertical distance between the centers of the two pressure measuring holes is 4 mm. The two pressure measuring holes of the probe head (2) are respectively connected to the two dynamic pressure sensors (18) and the signals are led out of the probe through the cable (8), wherein the No. 1 pressure measuring hole (21) corresponds to the No. 1 pressure sensor (181) and the No. 1 cable (81), and the No. 2 pressure measuring hole (22) corresponds to the No. 2 pressure sensor (182) and the No. 2 cable (82). In this embodiment, the diameter of the pressure measuring hole is 1 mm.

[0056] On the probe head (2), no diffuse holes (15) are developed within a range of three times the diameter of the pressure measuring hole No. 1 on the cylindrical surface away from the pressure measuring hole (21), and no diffuse holes are developed on the oblique surface where the pressure measuring hole No. 2 (22) is located, so as to avoid interference of the pressure measuring holes by steam generated by evaporative cooling. The diffuse holes (15) are developed on the remaining surfaces, and the probe head (2) is cooled by sweat cooling of the hemispherical surface of the hemispherical oblique cut body and impact cooling generated by the cooling water inlet pipe (6).

[0057] The sleeve (3) is a three-layer structure, comprising a first wall surface—a diverging wall surface (10), a second wall surface—an impact wall surface (11), and a third wall surface—a flow-limiting wall surface (12). A first cooling channel is formed between the first wall surface—the diverging wall surface (10), the second wall surface—the impact wall surface (11), and the second wall surface—the impact wall surface (11); a second cooling channel is formed between the second wall surface—the impact wall surface (11), the second wall surface—the impact wall surface (11), and the third wall surface—the flow-limiting wall surface (12); and a third cooling channel is formed between the third wall surface and the outer wall surface (13) of the probe support rod. The above three cooling channels are cooling water infiltration channels.

[0058] In this embodiment, the mounting seat (4) is in the shape of a racetrack and has a thickness of 3 mm. Two positioning holes (5) are formed on the mounting seat (4), and the diameter of the positioning holes (5) is 2 mm.

[0059] Six circumferential partition baffles (9) are evenly arranged circumferentially between the outer wall of the cooling water inlet pipe (6) and the first wall—the diverging wall (10) to reduce the negative influence of gravity on the uneven distribution of cooling water. The circumferential partition baffles penetrate the second wall—the impact wall (11), the second wall—the impact wall (11), the third wall—the flow limiting wall (12), and the fourth wall—the outer wall of the probe support rod (13), thereby circumferentially dividing the first cooling channel, the second cooling channel, the third cooling channel, and the cooling water return channel into six independent cooling areas. The six cooling water return channels correspond to the six independent cooling areas one by one.

[0060] The cooling water outlet pipe (7) is connected to the cooling water main circuit, and promptly discharges the cooling water whose temperature in the probe rises to a certain level but fails to enter the third flow channel between the outer wall surface (13) of the probe support rod and the flow-limiting wall surface (12). That is, the flowing cooling water further absorbs part of the heat that cannot be completely absorbed during the sweating cooling process through convective heat transfer, thereby better protecting the dynamic pressure sensor (18).

[0061] The surface of the first wall surface, the diverging wall surface (10), is provided with S-shaped cylindrical diverging holes (15), which are evenly distributed along the circumference and periodically staggered in the axial direction, forming a diverging wall surface (10) with evenly dense diverging holes. The diverging holes (15) penetrate the first wall surface, the diverging wall surface (10), and cooling water seeps out from the diverging holes to form a liquid film evaporation cooling outer wall surface of the sleeve (3).

[0062] The diverging hole (15) is an S-shaped cylindrical hole to prevent the cooling water from overflowing quickly and affecting the measurement accuracy when the water supply pressure is too high. In this embodiment, the diameter of the diverging hole (15) is 0.08 mm, and the angles between the two inclined lines in the broken line axis and the radial and horizontal directions of the probe support rod are both 50°.

[0063] The second wall surface—impact wall surface (11) is uniformly distributed with impact holes (16) on the surface of the second wall surface—impact wall surface (11), and the impact holes (16) connect the first cooling channel and the second cooling channel. Cooling water passes through the second wall surface—impact wall surface (11) from the second cooling channel into the first cooling channel, and performs impact cooling on the first wall surface—divergent wall surface (10). The impact holes (16) are straight holes and are axially staggered and periodically distributed on the second wall surface—impact wall surface (11). In this embodiment, the diameter of the impact holes (16) is 0.15 mm.

[0064] A plurality of groups of flow limiting holes (17) are evenly arranged on the surface of the third wall surface, the flow limiting wall surface (12). Since the thermal environments at different axial positions of the probe support rod (1) may be different, the required flow rates may also be different. Different numbers of flow limiting holes (17) can be opened at different axial positions of the probe support rod (1) according to the thermal environment of the probe to control the flow of cooling water entering different positions, thereby controlling the cooling effect at different positions. In this embodiment, the diameter of the flow limiting hole (17) is 0.2 mm.

[0065] The first cooling channel is provided with spoiler columns (14), which are evenly distributed in the circumferential direction and staggered periodically distributed in the axial direction to form a uniformly dense group of spoiler columns. The upper and lower end surfaces of the spoiler columns (14) are fixedly connected to the first wall surface - the diverging wall surface (10) and the second wall surface - the impact wall surface (11) to enhance the overall heat exchange performance. The diameter of the spoiler columns (14) is 0.1 mm.

[0066] The probe of the present invention can measure three-dimensional flow fields with a double-hole probe. In actual measurement, pressure data at different deflection angles can be obtained by rotating the probe or performing multiple measurements. The deflection angle calibration curve of the probe is obtained by fitting the curve. At the same time, the pitch angle coefficient is defined as:

[0067]

[0068] In the above formula, C pp is the pitch angle coefficient, P1 is the pressure measured by the No. 1 pressure measuring hole (21), P2 is the pressure measured by the No. 2 pressure measuring hole (22), P 1,max+40 is the pressure measured when the No. 1 pressure measuring hole (21) is deflected 40° in the positive direction corresponding to the maximum pressure position, P 1,max-40° It is the pressure measured when the No. 1 pressure measuring hole (21) is deflected 40° in the opposite direction corresponding to the maximum pressure position.

[0069] The present invention can select appropriate divergent hole layout parameters according to the actual high-temperature flow field temperature range, and select appropriate cooling water supply pressure according to the test environment pressure. Through the reasonable combination of three cooling methods of cooling water convection heat transfer cooling, impact cooling and evaporative heat absorption cooling, the cooling effect of the probe is effectively improved, and the probe part is effectively cooled by using the method of impact cooling combined with sweating cooling, which can greatly improve the dynamic response capability and operating temperature upper limit (up to 2500℃) of the pressure probe in high-temperature and strong unsteady flow fields.

Claims

1. A transpiration-cooled high-temperature water-cooled double-hole dynamic pressure probe for measuring subsonic three-dimensional flow fields, comprising a probe support rod (1), a probe head (2), a sleeve (3), a mounting seat (4), a positioning hole (5), a cooling water inlet pipe (6), a cooling water outlet pipe (7), a cable (8), a circumferential partition baffle (9), a first wall surface—a diverging wall surface (10), a second wall surface—an impact wall surface (11), a third wall surface—a flow-limiting wall surface (12), a fourth wall surface—an outer wall surface of the probe support rod (13), a dynamic pressure sensor (18), and a flow column (14), a diverging hole (15), an impact hole (16), and a flow-limiting hole (17); characterized in that: The probe head (2) is located at the front end of the probe support rod (1). The probe head (2) includes a cylindrical body with a common bottom surface and a hemispherical beveled body portion, and two dynamic pressure sensors (18) are independently packaged inside the probe head. The sleeve (3) is installed on the outside of the probe support rod (1). The mounting seat (4) is installed on the sleeve (3). The mounting seat (4) is provided with a positioning hole (5). The cooling water inlet pipe (6) and the cable (8) are both installed in the probe support rod (1). The cooling water outlet pipe (7) is installed on the sleeve (3) and behind the mounting seat (4). The cable (8) is installed in the probe support rod (1) and is respectively arranged on the periphery of the cooling water inlet pipe (6) along the circumferential direction. The probe support rod (1) is a double-layer structure, the inner layer is connected to the cooling water inlet pipe (6) as a cooling water inlet channel, and the outer layer is divided into six chambers by a circumferential partition baffle (9), and two dynamic pressure sensors (18) and corresponding cables (8) are respectively placed on the front and rear sides. Each chamber and the third cooling channel together serve as a cooling water circuit; The outer diameter of the probe support rod (1) is 2 mm to 5 mm, and the outer diameter of the corresponding sleeve (3) is 4 mm to 10 mm. The two are welded into a whole. The diameter of the cooling water inlet pipe (6) is 1 mm to 2 mm. The probe head (2) is a cylindrical portion whose axial length from the probe top to the end face is three times the outer diameter of the probe support rod (1). The probe head (2) is composed of a cylindrical end portion and a hemispherical beveled body with a common bottom surface. The diameter of the beveled body is the same as the diameter of the outer wall of the casing, and the angle between the beveled surface and the horizontal plane is 30° to 60°. A No. 1 pressure measuring hole (21) is opened on the cylindrical surface of the probe head (2), and a No. 2 pressure measuring hole (22) is opened on the oblique surface of the hemispherical bevel body, and the No. 2 pressure measuring hole (22) is located directly below the No. 1 pressure measuring hole (21), and the vertical distance between the centers of the two pressure measuring holes is 3 mm to 10 mm. The two pressure measuring holes on the probe head (2) are respectively connected to the two dynamic pressure sensors (18) and the signals are led out of the probe through the cable (8), wherein the No. 1 pressure measuring hole (21) corresponds to the No. 1 pressure sensor (181) and the No. 1 cable (81), and the No. 2 pressure measuring hole (22) corresponds to the No. 2 pressure sensor (182) and the No. 2 cable (82), and the diameter of the pressure measuring hole is 0.6 mm to 1.5 mm; On the probe head (2), no diffuse holes (15) are developed within a range of three times the diameter of the pressure measuring hole from the cylindrical surface of the No. 1 pressure measuring hole (21), and no diffuse holes are developed on the oblique surface where the No. 2 pressure measuring hole (22) is located, so as to prevent the steam generated by evaporative cooling from interfering with the pressure measuring hole. The diffuse holes (15) are developed on the remaining surfaces, and the probe head (2) is cooled by sweating cooling of the hemispherical surface of the hemispherical oblique cut body and impact cooling generated by the cooling water inlet pipe (6); The sleeve (3) is a three-layer structure, comprising a first wall surface—a diverging wall surface (10), a second wall surface—an impact wall surface (11), and a third wall surface—a flow-limiting wall surface (12). A first cooling channel is formed between the first wall surface—the diverging wall surface (10) and the second wall surface—the impact wall surface (11); a second cooling channel is formed between the second wall surface—the impact wall surface (11) and the third wall surface—the flow-limiting wall surface (12); and a third cooling channel is formed between the third wall surface and the outer wall surface (13) of the probe support rod. The above three cooling channels are cooling water infiltration channels. The mounting seat (4) is in the shape of a runway, and the thickness of the mounting seat (4) is 2 mm to 5 mm. The mounting seat (4) is provided with two or more positioning holes (5) suitable for other specific measurement occasions, and the diameter of the positioning hole (5) is 2 mm to 3 mm. Six circumferential partition baffles (9) are evenly arranged circumferentially between the outer wall of the cooling water inlet pipe (6) and the first wall—the diverging wall (10) to reduce the negative influence of gravity on the uneven distribution of cooling water. The circumferential partition baffles penetrate the second wall—the impact wall (11), the third wall—the flow limiting wall (12), and the fourth wall—the outer wall of the probe support rod (13), thereby circumferentially dividing the first cooling channel, the second cooling channel, the third cooling channel, and the cooling water return channel into six independent cooling areas. The six cooling water return channels correspond to the six independent cooling areas one by one. The cooling water outlet pipe (7) is connected to the cooling water main circuit, and promptly discharges the cooling water in the probe that has risen to a certain temperature but has not entered the third flow channel between the outer wall surface (13) of the probe support rod and the flow-limiting wall surface (12), that is, the flowing cooling water further absorbs part of the heat that has not been completely absorbed during the sweating cooling process through convective heat transfer, thereby better protecting the dynamic pressure sensor (18); The surface of the first wall surface - the diverging wall surface (10) is provided with S-shaped cylindrical diverging holes (15), which are evenly distributed along the circumference and staggered in the axial direction to form a diverging wall surface (10) with evenly dense diverging holes. The diverging holes (15) penetrate the first wall surface - the diverging wall surface (10), and cooling water seeps out from the diverging holes to form a liquid film evaporation cooling outer wall surface of the jacket (3); The diverging hole (15) is an S-shaped cylindrical hole to prevent the cooling water from overflowing quickly and affecting the measurement accuracy when the water supply pressure is too high. The diameter of the diverging hole (15) is 0.05 mm to 0.15 mm, and the angles between the two inclined lines in the broken line axis and the radial and horizontal directions of the probe support rod are both between 30° and 60°; Impact holes (16) are evenly distributed on the surface of the second wall surface - the impact wall surface (11), and the impact holes (16) connect the first cooling channel and the second cooling channel. Cooling water passes through the second wall surface - the impact wall surface (11) from the second cooling channel into the first cooling channel, and performs impact cooling on the first wall surface - the divergent wall surface (10). The impact holes (16) are straight holes and are axially staggered and periodically distributed on the second wall surface - the impact wall surface (11). The diameter of the impact holes (16) is 0.1 mm to 0.3 mm; A plurality of groups of flow limiting holes (17) are evenly arranged on the surface of the third wall surface, the flow limiting wall surface (12). Since the thermal environment at different axial positions of the probe support rod (1) may be different, the required flow rate is also different. According to the thermal environment where the probe is located, different numbers of flow limiting holes (17) are opened at different axial positions of the probe support rod (1) to control the flow rate of cooling water entering different positions, thereby controlling the cooling effect at different positions. The diameter of the flow limiting hole (17) is 0.2 mm to 0.4 mm. The first cooling channel is provided with spoiler columns (14), which are evenly distributed in the circumferential direction and staggered periodically distributed in the axial direction to form a uniformly dense group of spoiler columns. The upper and lower end surfaces of the spoiler columns (14) are fixedly connected to the first wall surface (divergent wall surface) (10) and the second wall surface (impact wall surface) (11) to enhance the overall heat exchange performance. The diameter of the spoiler columns (14) is 0.1 mm to 0.2 mm.

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