Water-cooling pressure measuring rake for combustion chamber

Abstract

The utility model relates to a water-cooling pressure measuring rake for combustion chamber, which comprises a water return pipe, a rake body mounting seat, a pressure measuring pipe, a cavity, a fixing seat and a water inlet pipe, the water return pipe, the fixing seat and the water inlet pipe are mounted at one end of the rake body mounting seat, the cavity is mounted at the other end of the rake body mounting seat, the water return pipe and the water inlet pipe are respectively communicated with the cavity, and the pressure measuring pipe is positioned in the cavity. One end of each pressure measuring pipe extends out of the side wall of the cavity, the other end of each pressure measuring pipe is installed on the fixing base, and the multiple pressure measuring pipes are arranged side by side. When in use, the pressure measuring pipe extends into a high-temperature flow field, so that the total pressure of a plurality of positions can be measured at the same time, and the total pressure distribution of the high-temperature flow field is efficiently obtained; the cavity is communicated with the water inlet pipe and the water return pipe, cooling water is used for cooling the pressure measuring pipe extending into the high-temperature flow field and the cavity, long-time stable measurement of total pressure is achieved, and accuracy of measured data is guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of ramjet engine testing technology, specifically to a water-cooled pressure testing rake for the combustion chamber. Background Technology

[0002] Measuring the total pressure in the combustion chamber through experiments is an important means of evaluating the combustion efficiency and performance of ramjet engines. However, the combustion chamber temperature can reach over 2000K, which places high demands on the total pressure measuring device: it must accurately measure the total pressure at multiple locations, while also preventing the measuring device from being ablated, burned through, or even melted in the high-temperature gas scouring environment.

[0003] Since pressure sensors cannot withstand high-temperature environments, current pressure measurements in high-temperature environments mostly employ probes to draw the pressure out of the high-temperature environment before measurement. At the same time, active cooling methods are used, such as air film cooling or water cooling, to cool the pressure probe and measuring device, preventing them from being burned and maintaining sufficient strength to prevent damage.

[0004] The air film cooling method has certain drawbacks in cooling the probe tip. If an opening is made near the tip for cooling, the cooling airflow will interfere with the flow field of the probe tip, resulting in measurement distortion. If no opening is made and heat is transferred between the probe structure and the gas through convection, the cooling efficiency is low and the probe is easily ablated.

[0005] Water cooling does not interfere with the flow field outside the measuring device, and water has a higher specific heat capacity, resulting in better cooling. However, existing water-cooled measuring devices either have high internal resistance and dead water zones, leading to poor cooling; or they are open-type, making it difficult to build up cooling water pressure and resulting in low cooling efficiency; and existing acquisition channels are generally single-channel, making it impossible to simultaneously acquire the total pressure at different locations in the flow field to obtain the total pressure distribution.

[0006] Analyzing the uniformity of the combustion flow field requires obtaining pressure data at multiple locations along the same measurement cross-section to acquire a pressure contour map of the combustion chamber for analysis. During measurement, it is crucial to minimize interference with the flow field and the chemical reactions within the combustion chamber. However, existing methods often use cylindrical shapes within the flow field, which may disrupt the original structure of the flow field during sampling, potentially affecting the combustion components and compromising the accuracy of the experimental measurements. Utility Model Content

[0007] This utility model addresses the existing technical problems by providing a water-cooled pressure measuring rake for the combustion chamber.

[0008] The technical solution of this utility model to solve the above-mentioned technical problems is as follows: A water-cooled pressure measuring rake for combustion chamber includes a return water pipe, a rake body mounting base, a pressure measuring tube, a cavity, a fixing base, and a water inlet pipe. The return water pipe, the fixing base, and the water inlet pipe are installed at one end of the rake body mounting base, and the cavity is installed at the other end of the rake body mounting base. The return water pipe and the water inlet pipe are respectively connected to the cavity. The pressure measuring tube is located in the cavity, one end of the pressure measuring tube extends out of the side wall of the cavity, and the other end of the pressure measuring tube is installed on the fixing base. Multiple pressure measuring tubes are provided, and the multiple pressure measuring tubes are arranged in parallel.

[0009] Based on the above technical solution, the present invention can be further improved as follows:

[0010] Preferably, the cavity is flat.

[0011] Preferably, the cavity is provided with a partition, which divides the cavity into a windward cavity and a leeward cavity. The return water pipe, the windward cavity, and the pressure measuring pipe are located on the same side of the partition, and the inlet end of the pressure measuring pipe is located on the windward cavity.

[0012] Preferably, a gap of 3mm-5mm is formed between the bottom of the partition and the bottom wall of the cavity.

[0013] Preferably, the bottom of the partition is provided with multiple through holes.

[0014] Preferably, the partition plate has multiple positioning grooves on its surface, and the pressure measuring tube is embedded in the positioning grooves.

[0015] Preferably, the inlet ends of the plurality of pressure measuring tubes are arranged along the length direction of the windward cavity.

[0016] Preferably, the mounting base is provided with multiple interfaces, one end of which is equipped with the pressure measuring tube, and the other end of which is equipped with a pressure sensor.

[0017] Preferably, the pressure measuring tube is made of high-temperature alloy tubing.

[0018] Preferably, the outer sides of both the windward side of the windward cavity and the leeward side of the leeward cavity are arc surfaces.

[0019] The beneficial effects of this utility model are:

[0020] (1) When in use, the pressure measuring tube is inserted into the high-temperature flow field, and the total pressure at multiple locations can be measured at the same time, so as to efficiently obtain the total pressure distribution of the high-temperature flow field;

[0021] (2) By connecting the cavity to the inlet and outlet water pipes, cooling water is used to cool the pressure measuring tube and the cavity that are inserted into the high-temperature flow field, so as to achieve long-term stable measurement of total pressure and ensure the accuracy of measurement data;

[0022] (3) When in use, simply insert the pressure rake into the high-temperature flow field, connect the pressure sensor and the inlet and outlet water pipes, and it can be used. The structure is simple and the operation is convenient.

[0023] (4) By setting the cavity to a flat shape, the unstable wake can be avoided from interfering with the subsequent flow field, thereby further improving the accuracy of the measurement.

[0024] (5) By cooling the pressure measuring tube in a closed cavity, the combustion components will not be changed. Multiple pressure measuring tubes can be arranged as needed to simultaneously measure the pressure at multiple radial positions, ensuring the accuracy of the measurement results.

[0025] (6) This water-cooled pressure measuring rake can be used not only for measuring the total pressure of the combustion chamber of a ramjet engine, but also for measuring the total pressure of the combustion chamber of other types of engines or in high-temperature environments, meeting the measurement needs under different high-temperature environments and improving the scope of application. Attached Figure Description

[0026] Figure 1 This is a three-dimensional schematic diagram of the water-cooled pressure measuring rake of this utility model;

[0027] Figure 2 This is a schematic diagram of the water-cooled pressure measuring rake of this utility model from another angle;

[0028] Figure 3 This is a cross-sectional schematic diagram of the water-cooled pressure measuring rake of this utility model;

[0029] Figure 4 This is a three-dimensional schematic diagram of the rake body mounting base of this utility model;

[0030] Figure 5 This is a cross-sectional schematic diagram of the rake body mounting base of this utility model;

[0031] Figure 6 This is a cross-sectional view of the rake body mounting base of this utility model from another angle;

[0032] Figure 7 This is a top view of the present invention in use;

[0033] Figure 8 This is a cross-sectional view of the present invention in use.

[0034] The attached diagram is labeled as follows: 1. Return water pipe; 2. Rake body mounting base; 3. Pressure measuring pipe; 4. Cavity; 41. Windward cavity; 42. Leeward cavity; 5. Fixing base; 6. Inlet water pipe; 7. Baffle plate; 71. Positioning groove; 8. Test piece. Detailed Implementation

[0035] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of 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 should fall within the protection scope of the present invention.

[0036] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. The terms "vertical," "upper," "lower," "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model 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 limitations on this utility model.

[0037] like Figures 1 to 8 As shown, this utility model discloses a water-cooled pressure measuring rake for a combustion chamber, including a return water pipe 1, a rake body mounting base 2, a pressure measuring tube 3, a cavity 4, a fixing base 5, and a water inlet pipe 6. The return water pipe 1, the fixing base 5, and the water inlet pipe 6 are installed at one end of the rake body mounting base 2, and the cavity 4 is installed at the other end of the rake body mounting base 2. The rake body mounting base 2 is made of nickel-based high-temperature alloy material, which has good high-temperature resistance. The rake body mounting base 2 has four through holes for fixing it to the outer wall of the test piece 8 and sealing it with copper gaskets. The return water pipe 1 and the water inlet pipe 6 are respectively connected to the cavity 4. The pressure measuring tube 3 is located inside the cavity 4. One end of the pressure measuring tube 3 extends out of the side wall of the cavity 4 to introduce airflow into the pressure measuring tube 3 and stagnate it. The other end of the pressure measuring tube 3 passes through the rake body mounting base 2 and is then installed on the interface of the fixing base 5. A pressure sensor is installed on the interface. The pressure sensor is used to measure the gas pressure inside the pressure measuring tube 3, thereby realizing the measurement of the gas pressure inside the combustion chamber.

[0038] Furthermore, multiple pressure measuring tubes 3 are provided, arranged side by side, with the number of interfaces corresponding to the number of pressure measuring tubes 3. These interfaces are spaced apart along the height of the mounting base 5. The return water pipe 1 and the inlet water pipe 6 are both high-temperature alloy steel pipes, welded to the rake body mounting base 2 respectively. The inlet water pipe 6 and the return water pipe 1 are connected to the water source via threaded joints. The water source is equipped with a water pump, which drives the cooling water circulation, improving the cooling effect on the pressure measuring tubes 3. The closed cavity 4 does not change the combustion components. Multiple pressure measuring tubes 3 can be arranged as needed to simultaneously measure the pressure at multiple radial positions in the combustion chamber. If four pressure measuring rakes are arranged circumferentially in the combustion chamber, refer to... Figure 7 and Figure 8 As shown, pressure values ​​at different radial and circumferential positions in the combustion chamber can be obtained simultaneously, thus facilitating accurate acquisition of the pressure distribution in the combustion chamber flow field.

[0039] In this embodiment, specifically, the cavity 4 is flat, that is, the cross-section of the cavity 4 is an elongated ellipse. Compared with the cylindrical pressure measuring device, the cavity 4 extending into the flow field is flat, which avoids the formation of unstable wakes that interfere with the subsequent flow field and ensures the accuracy of the measurement results.

[0040] Furthermore, a partition 7 is provided inside the cavity 4, dividing the cavity 4 into a windward cavity 41 and a leeward cavity 42. The return water pipe 1, the windward cavity 41, and the pressure measuring pipe 3 are located on the same side of the partition 7. The inlet end of the pressure measuring pipe 3 is located on the windward cavity 41, guiding the airflow pressure at the windward side into the pressure measuring pipe 3 to measure the air pressure. Since the pressure measuring pipe 3 is located inside the windward cavity 41, the temperature of the windward cavity 41 is higher. If the cooling water enters from the windward cavity 41, the cooling water flowing into the leeward cavity 42 will be at a higher temperature, resulting in limited cooling effect on the leeward cavity 42. Therefore, in this invention, the cooling water first enters the leeward cavity 42 through the inlet pipe 6 for cooling, and then cools the windward cavity 41 to ensure the overall cooling effect.

[0041] In this embodiment, a gap of 3mm-5mm is formed between the bottom of the partition 7 and the bottom wall of the cavity 4 to control the flow area of ​​the cooling water, increase the flow rate, ensure the cooling effect, and ensure that the cooling water flows fully to each area to avoid stagnant water areas, thereby further improving the cooling effect.

[0042] In other alternative embodiments, the bottom of the baffle 7 is provided with multiple through holes to further increase the flow rate and improve the cooling water circulation effect.

[0043] In this embodiment, the pressure measuring tube 3 is made of high-temperature alloy material, such as nickel-based high-temperature alloy material, which has good high-temperature strength, oxidation resistance, and hot corrosion resistance, ensuring normal measurement of flow field pressure. The inlet ends of multiple pressure measuring tubes 3 are arranged along the length of the windward cavity 41, enabling simultaneous measurement of pressure at multiple radial positions in the combustion chamber and improving the accuracy of the measurement results. In this embodiment, three pressure measuring tubes 3 are provided, and the three pressure measuring tubes 3 can work simultaneously to measure the total pressure at different positions in the combustion chamber, thereby providing a more comprehensive understanding of the pressure distribution in the combustion chamber.

[0044] Furthermore, the partition 7 has multiple positioning grooves 71 on its surface, extending along the length of the partition 7. These grooves are arranged side-by-side, and the pressure measuring tube 3 is embedded within one of them to fix it in place. Specifically, the three pressure measuring tubes 3 are arranged in a triangular shape within the cavity 4. Two positioning grooves 71 are provided, with two pressure measuring tubes 3 embedded within them. The third pressure measuring tube 3 is adjacent to the other two, forming a triangular arrangement that makes the overall structure more compact and reduces space occupation. The rake body mounting base 2 has corresponding triangular positioning through holes to effectively position the three pressure measuring tubes 3. These are then sealed by welding and adhesive to prevent shaking or cooling water leakage from gaps. The fixing base 5 is made of stainless steel and has three threaded holes on one side for connecting pressure sensors. On the other side, three through holes coaxial with the threaded holes are provided. The three pressure measuring tubes 3 are inserted into the three through holes and welded in place to ensure accurate measurement results. These three through holes are arranged along the length of the fixing base 5.

[0045] The wall thickness of cavity 4 is 2.5mm-3mm. In this embodiment, cavity 4 is made of 2.5mm thick GH4169 nickel-based high-temperature alloy sheet with sheet metal forming sidewalls. The windward side of the windward cavity 41 and the leeward side of the leeward cavity 42 are both arc surfaces. Specifically, the windward side of the windward cavity 41 and the leeward side of the leeward cavity 42 are both arc surfaces with a radius of R7.5mm-R8mm, further avoiding the formation of unstable wake interference with the subsequent flow field and ensuring the accuracy of the measurement results. After welding the partition 7, the pressure measuring tube 3 is installed, and then the other sidewall and bottom surface of cavity 4 are welded. Finally, the upper end of cavity 4 is welded to the rake body mounting base 2. The inlet end of the pressure measuring tube 3 extends 1.5mm-2mm beyond the windward cavity 41. The inlet ends of the three pressure measuring tubes 3 are set along the length of the windward cavity 41, thereby enabling simultaneous measurement of the pressure at multiple radial positions in the combustion chamber, improving measurement efficiency and the accuracy of the measurement results.

[0046] In use, insert cavity 4 into the test piece 8, and fix the rake mounting base 2 to the outer wall of the test piece 8, with the windward cavity 41 facing the direction of the high-temperature incoming flow in the test piece 8. The inlet pipe 6 and return pipe 1 are connected to cooling water, with the cooling water pressure set to 1 MPa. Connect the pressure sensor to the mounting base 5 to measure the total pressure of the high-temperature incoming flow. Simultaneously, cooling water flows from the inlet pipe 6 into the leeward cavity 42, then into the windward cavity 41, and finally out through the return pipe 1, achieving a better cooling effect and ensuring that cavity 4 and pressure measuring pipe 3 are not burned by the high-temperature gas.

[0047] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A water-cooled pressure gauge for a combustion chamber, characterized in that, The device includes a return water pipe (1), a rake body mounting base (2), a pressure measuring pipe (3), a cavity (4), a fixing base (5), and an inlet water pipe (6). The return water pipe (1), the fixing base (5), and the inlet water pipe (6) are installed at one end of the rake body mounting base (2), and the cavity (4) is installed at the other end of the rake body mounting base (2). The return water pipe (1) and the inlet water pipe (6) are respectively connected to the cavity (4). The pressure measuring pipe (3) is located inside the cavity (4). One end of the pressure measuring pipe (3) extends out of the side wall of the cavity (4), and the other end of the pressure measuring pipe (3) is installed on the fixing base (5). There are multiple pressure measuring pipes (3), and multiple pressure measuring pipes (3) are arranged side by side.

2. The water-cooled pressure gauge in the combustion chamber according to claim 1, characterized in that, The cavity (4) is flat.

3. The water-cooled pressure gauge in the combustion chamber according to claim 1 or 2, characterized in that, The cavity (4) is provided with a partition (7), which divides the cavity (4) into a windward cavity (41) and a leeward cavity (42). The return water pipe (1), the windward cavity (41) and the pressure measuring pipe (3) are located on the same side of the partition (7), and the inlet end of the pressure measuring pipe (3) is set on the windward cavity (41).

4. The water-cooled pressure gauge in the combustion chamber according to claim 3, characterized in that, A gap of 3mm-5mm is formed between the bottom of the partition (7) and the bottom wall of the cavity (4).

5. The water-cooled pressure gauge in the combustion chamber according to claim 3, characterized in that, The bottom of the partition (7) is provided with multiple through holes.

6. The water-cooled pressure gauge in the combustion chamber according to claim 3, characterized in that, The partition (7) has multiple positioning grooves (71) on its surface, and the pressure measuring tube (3) is embedded in the positioning grooves (71).

7. The water-cooled pressure gauge in the combustion chamber according to claim 3, characterized in that, The inlet ends of the plurality of pressure measuring tubes (3) are arranged along the length of the windward cavity (41).

8. The water-cooled pressure gauge in the combustion chamber according to claim 1, characterized in that, The mounting base (5) is provided with multiple interfaces, one end of which is equipped with the pressure measuring tube (3), and the other end is equipped with a pressure sensor.

9. The water-cooled pressure gauge in the combustion chamber according to claim 1, characterized in that, The pressure measuring tube (3) is made of high-temperature alloy tubing.

10. The water-cooled pressure gauge in the combustion chamber according to claim 3, characterized in that, The windward side of the windward cavity (41) and the leeward side of the leeward cavity (42) are both arc surfaces.

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