Shock tube driven pipe tunnel flow pulse direct connection test device and method

Abstract

The application relates to the technical field of fluid mechanics test devices, and provides a shock tube driven pipe tunnel flow pulse direct connection test device and method. The shock tube driven pipe tunnel flow pulse direct connection test device comprises a shock tube main body, a separation assembly, a test section assembly, a vacuum chamber, a parameter measurement assembly and a driving gas control assembly. The shock tube driven pipe tunnel flow pulse direct connection test device can reproduce pipe tunnel through flow and full working condition flow, accurately simulate a wide speed range pipe tunnel aerodynamic environment, generate controllable uniform test airflow through pulse driving of the shock tube, and realize the invention purpose of low-cost and high-fidelity pipe tunnel flow characteristic and vehicle aerodynamic performance test through cooperation of multiple assemblies and a multi-dimensional parameter measurement system. In addition, the application further provides a method applied to the shock tube driven pipe tunnel flow pulse direct connection test device.

Description

Technical Field

[0001] This application relates to the technical field of fluid dynamics testing devices, and in particular to a shock tube driven tube-tunnel flow pulse direct connection test device and method. Background Technology

[0002] The flow characteristics of both through-flow and congestion within a tunnel are a crucial foundation for the development of engineering technologies related to pipeline trains and tunnel launches. Currently, experimental methods used to study the flow characteristics of tunnels are mainly divided into three categories: large-scale test line testing, wind tunnel testing, and special-purpose testing. All these methods are used to reproduce the flow state within the tunnel, obtain the aerodynamic parameters of the vehicle in the tunnel environment, and provide experimental data support for the research and development of related systems.

[0003] Large-scale test line testing involves constructing full-size or large-scale test tunnels, equipping them with corresponding propulsion systems, and conducting operational tests on actual vehicles or large-scale models to directly acquire flow-related data for the entire process. Wind tunnel testing uses wind tunnel equipment to generate inflow with set parameters, installs a scaled-down model within the test section, and conducts aerodynamic tests related to pipe and tunnel flow. Specialized tests use air guns or magnetic levitation propulsion systems to drive a scaled-down model at high speed within the pipe, thereby replicating the flow state within the pipe and tunnel and measuring relevant parameters.

[0004] Existing testing methods all have certain limitations in application. Large-scale test lines are costly to construct and can only support tests under low-to-medium speed flow conditions, making it difficult to cover a wide velocity range of pipe and tunnel flow conditions. Wind tunnel tests struggle to stably establish congested flow states within pipe and tunnel spaces, and the incoming flow is easily affected by the upward movement of congestion shock waves, failing to meet the complex and variable requirements of pipe and tunnel flow conditions. Specialized tests suffer from poor operating speed stability, high measurement uncertainty, and high complexity in equipment construction and operation. These limitations collectively make it difficult for existing technologies to efficiently reproduce the real-world states of different flow modes within pipe and tunnels at a low cost. Summary of the Invention

[0005] In view of this, this application aims to provide a shock tube driven tube-tunnel flow pulse direct connection test device and method to solve the above-mentioned technical problems.

[0006] To achieve the above objectives, the technical solution of this application is implemented as follows: In a first aspect, this application proposes a shock tube-driven tube-tunnel flow pulse direct connection test device, comprising: The main body of the shock tube is a tubular structure with a smooth internal cavity of uniform cross-section, and the tube wall is sealed and one end is sealed. The separation components consist of two parts: one part is fixedly installed inside the shock tube body to divide the internal cavity of the shock tube body into an independent driving chamber and a driven chamber; the other part is fixedly installed at the outlet end of the shock tube body. The test section assembly is a tubular structure with a test cavity, open at both ends. Its inlet end is coaxially and sealed to the outlet end of the shock tube body. Its internal cavity is a tunnel-to-short-scale structure of the test tube and is provided with a mounting position for a scaled-down model of a vehicle. Its rear part is a tubular structure with an expansion and extension function. The vacuum chamber has its inlet end connected to the outlet end of the test section component; The measurement components are respectively connected to the shock tube body, the test section components, and the scaled-down aircraft model installed inside them; The gas control components, including a vacuum pump and a high-pressure gas source, are connected to the shock tube body and the vacuum chamber via pipelines.

[0007] Furthermore, the shock tube body includes a driving section and a driven section that are coaxially and sealed and fixedly connected in sequence; The internal cavity of the drive section is the drive chamber, and the side wall of the drive section is provided with an inflation and deflation interface communicating with the gas control component; the internal cavity of the driven section is the driven chamber, and the side wall of the driven section is provided with an inflation and deflation interface communicating with the gas control component; the vacuum chamber is provided with a deflation interface communicating with the gas control component.

[0008] Furthermore, the separating assembly consists of a diaphragm clamping flange and a separating diaphragm, including a first separating assembly and a second separating assembly; The first separation component is sealed between the connection end faces of the driving section and the driven section; the second separation component is sealed between the connection section of the driven section and the test section component.

[0009] Furthermore, the test section assembly includes a test section cylinder, a model mounting base, an optical observation window, a sensor mounting interface, a transition section, and a follow-up pipe section; The inlet end of the test section cylinder is sealed and fixedly connected to the second separation component. The model mounting base is fixedly installed at the bottom of the internal cavity of the test section cylinder. The optical observation window is symmetrically opened on the side wall of the test section cylinder, and the optical observation window is sealed and fixed to the side wall of the test section cylinder. The sensor mounting interface is arranged on the outer wall of the test section cylinder and communicates with the internal cavity and internal model of the test section cylinder. The transition section is symmetrically arranged at both ends of the inner wall of the test section cylinder. The inlet is a circular cross-section with the same as the inner cavity of the shock tube body, and the outlet is an irregular cross-section that matches the inner wall cavity of the test section cylinder. One end of the extension tube is connected to the test section cylinder, and the other end extends into the interior of the vacuum chamber.

[0010] Furthermore, the measurement component includes a pressure measurement subunit, a temperature measurement subunit, a flow field observation subunit, and an aerodynamic parameter acquisition subunit; The pressure measurement subunit and temperature measurement subunit are respectively sealed and fixedly connected to the test section cylinder and shock tube body through the sensor mounting interface; the flow field observation subunit is set in a position corresponding to the optical observation window; the signal acquisition end of the aerodynamic parameter acquisition subunit is electrically connected to the sensor on the scaled-down vehicle model.

[0011] Furthermore, the second separation component may or may not be installed depending on the test conditions. When the diaphragm is installed, the separation diaphragm is sealed between the connection end faces of the driven section and the transition section by the diaphragm clamping flange.

[0012] Furthermore, the vacuum chamber includes a vacuum pump assembly, a chamber body, and a vacuum degree measuring instrument; The pumping end of the vacuum pump group is connected to the cavity of the shock tube body and the test section assembly through the vacuum valve group, and the detection end of the vacuum degree measuring instrument is connected to each cavity. The gas control assembly includes a high-pressure gas cylinder group, a vacuum pump group, a pressure regulating valve group, a gas filling valve group, a vacuum valve group, and a pressure monitoring unit; The outlet of the high-pressure gas cylinder group is connected to the driving chamber and the driven chamber of the shock tube body through the pressure regulating valve group and the charging valve; the vacuum pump group is connected to the driving chamber and the driven chamber of the shock tube body and the vacuum chamber through the vacuum valve group; the detection end of the pressure monitoring unit is connected to the driving chamber, the driven chamber and the vacuum chamber.

[0013] Secondly, this application proposes a method for a direct-connection test device for pipe-tunnel flow pulses driven by a shock tube, comprising the following steps: S1, Inverse design of test parameters: Based on the actual operating conditions of the pipe tunnel to be simulated, and combined with the similarity criteria of pipe tunnel flow, determine the required airflow Mach number, pressure, and temperature parameters for the test, and inverse design the initial operating parameters of the driving section and the driven section of the shock tube body. S2, Test preparation: Fix the scaled-down vehicle model in the internal mounting position of the test section assembly, complete the diaphragm clamping and sealing assembly of the shock tube body and the test section assembly, adjust the test section cavity and vacuum chamber to the set initial vacuum degree through the gas control component, adjust the driven chamber of the shock tube body to the required initial pressure, and fill the driven chamber of the shock tube body with the set parameters of driving gas. S3, test airflow generation, the diaphragm of the first separation component ruptures, the high-pressure gas in the driving section enters the driven section to form an incident shock wave, and a uniform airflow with set parameters is generated in the driven section. S4, the flow field of the pipe tunnel is established. The incident shock wave arrives at the second separation component of the test section and enters the test section component directly or causes the second diaphragm to rupture. It sweeps the scaled-down vehicle model and establishes a pipe tunnel flow field or blockage flow field corresponding to the actual working conditions in the test section. S5, Test data acquisition: The airflow parameters, flow field structure parameters, and aerodynamic parameters of the scaled-down vehicle model are synchronously acquired through the measurement components during the test until the test airflow window disappears and the test ends. S6, Post-test processing: The cavity is vented and depressurized through the extended pipe section, the collected test data is organized, and the flow characteristics of the pipe tunnel are analyzed.

[0014] Furthermore, in step S1, for the pipe-tunnel flow condition of the choking mode, the choking airflow parameters in front of the test model are obtained by quasi-one-dimensional calculation, and the initial operating parameters of the shock tube body under the direct connection test mode of the stagnation chamber are obtained by reverse design. In step S2, the gas control component is used to adjust the driving section and the driven section to a set pressure. In step S3, under congested flow conditions, the incident shock wave is reflected at the inlet end of the test section component to form a reflected shock wave, generating a high-pressure and high-temperature airflow in the sump chamber that matches the congested airflow parameters in front of the vehicle at the end of the driven section. In step S4, under congested flow conditions, the diaphragm of the second separation component ruptures, and the high-pressure airflow in the sump enters the test section component, establishing a fully expanded congested flow field that matches the actual working conditions.

[0015] Furthermore, the reverse design of the test parameters in step S1 follows the core principles of geometric similarity, Mach number similarity, and Reynolds number similarity to ensure that the blockage ratio of the scaled-down model is consistent with that of the real aircraft and that the Mach number of the test airflow is consistent with that of the real incoming flow. For high Reynolds number pipe tunnel flow conditions, the Reynolds number similarity requirements are relaxed based on the flow self-modeling property, and the test Reynolds number is controlled to the target level by adjusting the pressure parameters of the test airflow.

[0016] Compared with existing technologies, the shock tube-driven tube tunnel flow pulse direct connection test device and method proposed in this application have the following advantages: (1) This application achieves a complete closed-loop construction of a pipe-tunnel flow pulse direct connection test device by coordinating the shock tube body, the partitioning component, the test section component, the vacuum chamber, the measurement component, and the gas control component. One of the two partitioning components is fixedly installed inside the shock tube body, dividing its internal cavity into an independent driving chamber and a driven chamber. The other is fixedly installed at the outlet end of the shock tube body. The test section component is coaxially and sealed to the outlet end of the shock tube body. Its internal cavity is set as a scaled-down structure of the pipe-tunnel to be tested and configured with the mounting position of the scaled-down vehicle model. The rear is a tubular structure with expansion and extension function. The inlet end of the vacuum chamber is connected to the outlet end of the test section component. The measurement component is connected to the shock tube body, the test section component, and the scaled-down vehicle model installed inside. The gas control component is connected to the chambers of the shock tube body and the vacuum chamber through pipelines. This achieves a complete closed-loop construction of the pipe-tunnel flow pulse direct connection test device, which can stably generate a uniform test airflow with set parameters and establish a pipe-tunnel flow field corresponding to the real working conditions. This provides a reliable hardware carrier for the experimental research of pipe-tunnel flow characteristics.

[0017] (2) This application achieves precise control of test airflow parameters and flexible adjustment of test chamber vacuum degree through the drive section and driven section coaxially and sealed and fixedly connected by the shock tube body, the first and second separation components consisting of diaphragm clamping flange and separation diaphragm set by the separation component, the test section cylinder, model mounting base, optical observation window, sensor mounting interface, transition section and extension pipe section set by the test section component, the pressure measurement subunit, temperature measurement subunit, flow field observation subunit and aerodynamic parameter acquisition subunit set by the measurement component, and the vacuum pump group, vacuum degree measuring instrument and high pressure gas cylinder group, pressure regulating valve group, gas filling valve group, vacuum valve group and pressure monitoring unit set by the vacuum chamber. It can adapt to different pipe tunnel flow modes and be compatible with multiple test modes. At the same time, it can perform comprehensive and synchronous precise measurement of airflow parameters, flow field structure and aerodynamic parameters of scaled-down aircraft model during the test, effectively broadening the applicable working conditions range of the test device and improving the comprehensiveness and accuracy of test data acquisition.

[0018] (3) This application is carried out through standardized steps of reverse design of test parameters, test preparation, test airflow generation, establishment of pipe and tunnel flow field, test data acquisition and post-test processing. By combining the actual operating conditions of the pipe and tunnel to be simulated with the pipe and tunnel flow similarity criteria, the required airflow Mach number, pressure and temperature parameters are determined and the initial operating parameters of the shock tube body are obtained by reverse design. By following the core criteria of geometric similarity, Mach number similarity and Reynolds number similarity, ensuring that the blockage ratio of the scaled model is consistent with that of the real aircraft, and ensuring that the test airflow is consistent with the Mach number of the real incoming flow, the key test parameters are controlled. The standardized and controllable conduct of the direct connection test of pipe and tunnel flow is realized. It can accurately reproduce the pipe and tunnel flow characteristics under different modes, effectively improve the accuracy, stability and repeatability of the test results, and provide reliable test method support for the systematic analysis of pipe and tunnel flow characteristics. Attached Figure Description

[0019] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the structure of the shock tube driven tube tunnel flow pulse direct connection test device described in the embodiments of this application; Figure 2 This is a schematic diagram of the side structure of the shock tube driven tube-tunnel flow pulse direct connection test device described in the embodiments of this application; Figure 3 This is a cross-sectional structural diagram of the test section and vacuum chamber described in the embodiments of this application; Figure 4 This is a schematic diagram of the forward structure of the test section described in the embodiments of this application.

[0020] Explanation of reference numerals in the attached figures: 1. Shock tube body; 101. Driving section; 102. Driven section; 2. Separation assembly; 201. First separation assembly; 202. Second separation assembly; 3. Test section assembly; 301. Test section cylinder; 302. Model mounting base; 303. Optical observation window; 304. Transition section; 305. Extension section; 4. Vacuum chamber. Detailed Implementation

[0021] To make the technical solution and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0023] Furthermore, it should be noted that in the description of this application, if terms such as "upper," "lower," "inner," or "outer" appear, indicating orientation or positional relationship, these are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this application 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, and therefore should not be construed as a limitation on this application. In addition, if terms such as "first" or "second" appear, they are also used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] Furthermore, in the description of this application, unless otherwise expressly defined, the terms "installation," "connection," "joining," and "connector" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application in light of the specific circumstances.

[0025] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0026] The present application will now be described in detail through exemplary embodiments. However, it should be understood that, without further description, elements, structures, and features in one embodiment may be advantageously incorporated into other embodiments.

[0027] This application relates to the field of pneumatic testing technology for pipe and tunnel flow, and in particular to a shock tube driven pulse direct connection test device and method for pipe and tunnel flow.

[0028] Reference Figure 1The shock tube-driven tube-tunnel flow pulse direct-connection test device provided in this application includes a shock tube body 1, a separation component 2, a test section component 3, a vacuum chamber 4, a measurement component, and a gas control component. The shock tube body 1 is a tubular structure with a smooth internal cavity of uniform cross-section. The tube wall is sealed and one end is sealed, providing a stable bearing space for the generation of test gas flow. There are two separation components 2, which serve as two sets of sandwich sections and diaphragm structures. They can divide the device into three independent pressure zones from the perspective of the pre-gas. The first zone is the driving chamber corresponding to the driving zone, the second zone is the driven chamber corresponding to the driven zone, and the third zone is the cavity connecting the test section component and the vacuum chamber. The three zones are sequentially isolated by the two separation components 2. The test section assembly 3 is a tubular structure with a test chamber, open at both ends. Its inlet end is coaxially and sealed to the outlet end of the shock tube body 1. Its internal cavity is a scaled-down structure of the test tube and includes a mounting position for a scaled-down vehicle model. Its rear section is a tubular structure with expansion and extension capabilities, providing a stable mounting base for the scaled-down vehicle model and ensuring stable axial airflow into the test chamber, preventing airflow disturbances from interfering with the test results. The inlet end of the vacuum chamber 4 is connected to the outlet end of the test section assembly 3, forming a unified pressure range with the chamber of the test section assembly 3. This provides the necessary vacuum environment for the test chamber and allows for pressure relief and airflow channeling after the test. Measurement components are connected to the shock tube body 1, the test section assembly 3, and the scaled-down vehicle model installed inside, enabling real-time acquisition of relevant parameters during the test. The gas control component is connected to the driving chamber, the driven chamber, the test section component cavity, and the vacuum chamber, enabling vacuuming operations in each chamber. Simultaneously, it allows for independent inflation and pressure control of the driving and driven chambers. Through the coordinated operation of these components, the stable generation and controllable adjustment of the airflow required for pipe-tunnel flow tests can be achieved, fully replicating the flow conditions during actual pipe-tunnel operation. This provides a stable and reliable hardware platform for experimental research on pipe-tunnel flow characteristics, while simplifying the overall structure of the experimental device and reducing the cost and operational difficulty of conducting experiments.

[0029] Reference Figure 1 and Figure 2The shock tube body 1 includes a drive section 101 and a driven section 102, which are coaxially and sealed together in sequence. The internal cavity of the drive section 101 is the drive chamber. The side wall of the drive section 101 has inflation and evacuation ports connected to the gas control assembly, enabling stable vacuuming of the drive chamber and filling and parameter adjustment of the drive gas. The internal cavity of the driven section 102 is the driven chamber. The side wall of the driven section 102 has inflation and evacuation ports connected to the gas control assembly, enabling stable vacuuming of the driven chamber and filling and pressure adjustment of the test gas to match the parameter requirements of different test conditions. The vacuum chamber 4 has an evacuation port connected to the gas control assembly, enabling vacuuming between the vacuum chamber and the connected test section assembly cavity. By splitting the shock tube body 1 into a coaxially connected driving section 101 and driven section 102, independent parameter control of the driving chamber and the driven chamber can be achieved, further improving the control accuracy of the test airflow parameters, while facilitating the processing, assembly and daily maintenance of the device.

[0030] Reference Figure 1 The separation assembly 2 consists of a diaphragm clamping flange and a separation diaphragm, including a first separation assembly 201 and a second separation assembly 202. The first separation assembly 201 is sealed between the connection end faces of the driving section 101 and the driven section 102. The diaphragm clamping flange seals and holds the separation diaphragm, ensuring complete isolation between the driving chamber and the driven chamber in their initial state, forming an independent pressure zone. At the same time, when the pressure in the driving chamber reaches a set threshold, the separation diaphragm will rupture stably in a preset manner, thereby ensuring the controllability and consistency of the test airflow generation process and improving the repeatability of test results from different batches. The second separation component 202 is sealed between the connection end faces of the driven section 102 and the test section component 3. The separation diaphragm can be installed or not depending on the test conditions. When the separation diaphragm is installed, the separation diaphragm is clamped between the connection end faces of the driven section 102 and the transition section 304 by the diaphragm clamping flange, so that the driven chamber and the chambers of the test section component 3 and the vacuum chamber 4 form independent pressure zones. When the separation diaphragm is not installed for the flow conditions, the chamber of the driven section 102 is connected to the chambers of the test section component 3 and the vacuum chamber 4, forming a unified pressure zone.

[0031] Reference Figure 1 , Figure 2 , Figure 3 and Figure 4The test section component 3 includes a test section cylinder 301, a model mounting base 302, an optical observation window 303, a sensor mounting interface, a transition section 304, and a follow-up pipe section 305. The inlet end of the test section cylinder 301 is sealed and fixedly connected to the second separation component 202, providing a closed test space for establishing the flow field in the tunnel. The model mounting base 302 is fixedly installed at the bottom of the internal cavity of the test section cylinder 301, providing a stable mounting structure for the scaled-down vehicle model, ensuring the stability of the model's position during the test, and preventing airflow impact from causing model displacement that could affect the test results. The optical observation windows 303 are symmetrically arranged on the side walls of the test section cylinder 301 and are sealed and fixed to the side walls of the test section cylinder 301, providing a visualization channel for flow field observation while ensuring the airtightness of the test cavity. The sensor mounting interface is located on the outer wall of the test section cylinder 301 and is connected to the internal cavity and internal model of the test section cylinder 301. It can provide a standardized mounting interface for various measurement sensors, ensuring the accuracy of measurement data. The transition section 304 is symmetrically arranged at both ends of the inner wall of the test section cylinder 301. The inlet is a circular cross-section with the same diameter as the inner cavity of the shock tube body 1, and the outlet is an irregular cross-section that matches the inner wall cavity of the test section cylinder 301. This can achieve a smooth transition between cavities with different cross-sections, reduce the disturbance of airflow at the cross-sectional change point, and ensure the uniformity of airflow entering the test section cylinder 301. One end of the extension pipe section 305 is connected to the test section cylinder 301, and the other end extends into the interior of the vacuum chamber 4. This can achieve smooth guidance of the test airflow, avoid reverse interference of the airflow depressurization process after the test on the internal flow field of the test section, and extend the window time of the effective test airflow. By coordinating the components of the test section assembly 3, a pipe tunnel flow field that matches the actual working conditions can be stably established within the test section. This provides comprehensive adaptation conditions for flow field observation and parameter measurement during the test process, further enhancing the comprehensiveness of the test and the accuracy of the data.

[0032] Reference Figure 1 and Figure 2The measurement components include a pressure measurement subunit, a temperature measurement subunit, a flow field observation subunit, and an aerodynamic parameter acquisition subunit. The pressure and temperature measurement subunits are sealed and fixedly connected to the test section cylinder 301 and the shock tube body 1, respectively, via sensor mounting interfaces, enabling real-time and accurate acquisition of airflow pressure and temperature parameters inside the shock tube body 1 and the test section cylinder 301 during the experiment. The flow field observation subunit is positioned correspondingly to the optical observation window 303, allowing for visual observation and recording of the flow field structure inside the test section. The signal acquisition end of the aerodynamic parameter acquisition subunit is electrically connected to the sensors on the scaled-down vehicle model, enabling real-time acquisition of the aerodynamic parameters of the scaled-down vehicle model during the experiment. Through the coordinated setup of multiple types of measurement subunits, simultaneous and comprehensive acquisition of airflow parameters, flow field structure parameters, and model aerodynamic parameters can be achieved during the experiment, obtaining complete multi-dimensional data on the pipe tunnel flow process and providing comprehensive and reliable data support for subsequent analysis of pipe tunnel flow characteristics.

[0033] Reference Figure 1 The vacuum chamber 4 includes a vacuum pump assembly, a chamber body, and a vacuum level measuring instrument. The pumping end of the vacuum pump assembly is connected to the driving chamber, the driven chamber, and the chamber of the test section assembly 3 of the shock tube body 1 via vacuum valves, enabling independent vacuuming operations for each chamber and the connected chambers to adjust them to the initial vacuum level required for the experiment. The vacuum level measuring instrument's detection end is connected to each chamber, allowing real-time monitoring of the vacuum level to ensure that the vacuum parameters meet the experimental requirements. The gas control assembly includes a high-pressure gas cylinder assembly, a vacuum pump assembly, a pressure regulating valve assembly, a charging valve assembly, a vacuum valve assembly, and a pressure monitoring unit. The outlet of the high-pressure gas cylinder assembly is connected to the driving chamber and the driven chamber of the shock tube body 1 via the pressure regulating valve assembly and the charging valve assembly, providing stable high-pressure gas to both chambers. Simultaneously, the pressure regulating valve assembly and the charging valve assembly enable independent and precise control of the gas charging process in both chambers. The vacuum pump unit is connected to the driving chamber and driven chamber of the shock tube body 1, as well as the vacuum chamber 4, via a vacuum valve assembly, enabling independent vacuuming operations for each chamber. The pressure monitoring unit's detection end is connected to the driving chamber, driven chamber, and vacuum chamber 4, allowing real-time monitoring of pressure parameters within each chamber to ensure gas parameters meet experimental design requirements. Through the coordinated setup of the vacuum chamber 4 and gas control components, precise control and real-time monitoring of initial parameters for each chamber of the experimental setup are achieved, adapting to segmented pressure setting requirements under different operating conditions. This further enhances the controllability of the experimental process and the accuracy of experimental parameters, while ensuring the safety of the experimental setup during operation.

[0034] This application also provides a method for direct connection test of pipe-tunnel flow based on shock tube pulse drive. The method is applied to the above-mentioned shock tube driven pipe-tunnel flow pulse direct connection test device and includes the following steps.

[0035] Step S1 is the reverse design of test parameters. Based on the actual operating conditions of the pipe tunnel to be simulated and combined with the similarity criteria of pipe tunnel flow, the required airflow Mach number, pressure and temperature parameters are determined. The initial operating parameters of the driving section 101 and driven section 102 of the shock tube body are obtained by reverse design.

[0036] Step S2 is for test preparation. The scaled-down vehicle model is fixedly installed in the internal mounting position of the test section component 3. According to the test conditions, the diaphragm clamping and sealing assembly of the first separation component 201 is completed. For the clogging condition, the diaphragm clamping and sealing assembly of the second separation component 202 is completed. For the flow condition, the separation diaphragm of the second separation component 202 is not installed. The overall sealing assembly of the device is completed. The driving chamber, the driven chamber, the test section component 3 cavity and the vacuum chamber 4 are evacuated by the gas control component. For the three pressure conditions, the driving chamber, the driven chamber, the test section component 3 and the vacuum chamber 4 are adjusted to the set initial pressure. For the two pressure conditions of flow, the driving chamber is adjusted to the set initial pressure, the driven chamber, the test section component 3 and the vacuum chamber 4 are adjusted to the same set initial pressure, and the test gas with set parameters is injected into the driving chamber and the driven chamber of the shock tube body 1.

[0037] Step S3 is the generation of test airflow. The diaphragm of the first separation component 201 ruptures, and the high-pressure gas in the driving section 101 enters the driven section 102 to form an incident shock wave, generating a uniform airflow with set parameters in the driven section 102.

[0038] Step S4 establishes the flow field in the tunnel. When the incident shock wave reaches the position of the second separation component 202, for the obstruction condition where the separation diaphragm is installed, the incident shock wave causes the diaphragm of the second separation component 202 to rupture and enter the test section component 3. For the flow condition where the separation diaphragm is not installed, the incident shock wave directly enters the test section component 3, sweeps the scaled-down vehicle model, and establishes the tunnel flow or obstruction flow field corresponding to the real condition in the test section.

[0039] Step S5 involves data acquisition, which uses measurement components to synchronously collect airflow parameters, flow field structure parameters, and aerodynamic parameters of the scaled-down vehicle model during the test until the test airflow window disappears, at which point the test ends.

[0040] Step S6 is the post-test processing, which involves venting and depressurizing the cavity through the extended pipe section 305, organizing the collected test data, and analyzing the flow characteristics of the pipe tunnel. Through the standardized test procedures described above, direct-connection pipe tunnel flow tests can be completed in a standardized and controllable manner, stably reproducing various flow states during actual pipe tunnel operation, ensuring the consistency of the test process and the reliability of the test results, while simplifying the test operation process and reducing the difficulty of conducting pipe tunnel flow tests.

[0041] For the choked tunnel flow condition, in step S1, the choked airflow parameters before the test model are obtained through quasi-one-dimensional calculation, and the initial operating parameters of the shock tube body 1 under the direct-connection test mode are obtained through back-design. In step S2, the driving section 101 and the driven section 102 are adjusted to the set pressure through the gas control component. In step S3, the incident shock wave is reflected at the inlet end of the test section component 3 to form a reflected shock wave, generating a high-pressure and high-temperature airflow in the choked chamber that matches the choked airflow parameters before the vehicle at the end of the driven section 102. In step S4, the diaphragm of the second separation component 202 ruptures, and the high-pressure airflow in the choked chamber enters the test section component 3, establishing a fully expanded choked flow field that matches the actual operating conditions. Through the targeted adjustments in the above steps, the pipe tunnel flow characteristics under the choked mode can be accurately reproduced, improving the uniformity of the test airflow and the effective test time under this condition, while ensuring the matching degree between the test results and the actual operating conditions, further improving the accuracy of the test data.

[0042] The reverse design of experimental parameters in step S1 follows the core principles of geometric similarity, Mach number similarity, and Reynolds number similarity, ensuring that the blockage ratio of the scaled-down model is consistent with that of the real aircraft, and that the Mach number of the experimental airflow is consistent with that of the real incoming flow. For high Reynolds number pipe-tunnel flow conditions, the Reynolds number similarity requirements are relaxed based on the flow self-modeling property, and the experimental Reynolds number is controlled to the target order of magnitude by adjusting the pressure parameters of the experimental airflow. By following the above similarity principles, the core characteristics of real pipe-tunnel flow can be accurately reproduced under scaled-down experimental conditions, while reducing the hardware requirements for conducting the experiment. This further broadens the range of operating conditions that the experimental method can be adapted to, and improves the versatility and practicality of the experimental method, while ensuring the validity of the experimental results.

[0043] The above descriptions are merely some embodiments of this application and are not intended to limit this application. The technical features or structures in the foregoing different embodiments can be arbitrarily combined to form other specific technical solutions as needed. For those skilled in the art, this application can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of the claims of this application.

Claims

1. A shock tube-driven tube tunnel flow pulse direct connection test device, characterized in that, include: The shock tube body (1) is a tubular structure with a smooth internal cavity of equal cross-section, and the tube wall is sealed and one end is sealed. The separation component (2) consists of two parts. One part is fixedly installed inside the shock tube body (1) to divide the internal cavity of the shock tube body (1) into an independent driving chamber and a driven chamber. The other part is fixedly installed at the outlet end of the shock tube body (1). The test section component (3) is a tubular structure with a test cavity, open at both ends. Its inlet end is coaxially sealed and fixedly connected to the outlet end of the shock tube body (1). Its internal cavity is a tunnel-to-short-scale structure of the test tube and is provided with a mounting position for a scaled-down model of a vehicle. Its rear part is a tubular structure with an expansion and extension function. The vacuum chamber (4) has its inlet end connected to the outlet end of the test section assembly (3); The measurement components are respectively connected to the shock tube body (1), the test section component (3) and the scaled-down aircraft model installed inside it; The gas control components, including a vacuum pump and a high-pressure gas source, are connected to the shock tube body (1) and the vacuum chamber (3) via pipelines.

2. The shock tube driven tube tunnel flow pulse direct connection test device according to claim 1, characterized in that, The shock tube body (1) includes a driving section (101) and a driven section (102) that are coaxially sealed and fixedly connected in sequence. The internal cavity of the drive section (101) is the drive chamber, and the side wall of the drive section (101) is provided with an inflation and deflation interface that communicates with the gas control component; the internal cavity of the driven section (102) is the driven chamber, and the side wall of the driven section (102) is provided with an inflation and deflation interface that communicates with the gas control component; the vacuum chamber (4) is provided with a deflation interface that communicates with the gas control component.

3. The shock tube driven tube tunnel flow pulse direct connection test device according to claim 2, characterized in that, The separation assembly (2) consists of a diaphragm clamping flange and a separation diaphragm, including a first separation assembly (201) and a second separation assembly (202). The first separation component (201) is sealed between the connecting end faces of the driving section (101) and the driven section (102); the second separation component (202) is sealed between the connecting section of the driven section (102) and the connecting section of the test section component (3).

4. The shock tube driven tube tunnel flow pulse direct connection test device according to claim 3, characterized in that, The test section assembly (3) includes a test section cylinder (301), a model mounting base (302), an optical observation window (303), a sensor mounting interface, a transition section (304), and a follow-up pipe section (305). The inlet end of the test section cylinder (301) is sealed and fixedly connected to the second separation component (202); the model mounting base (302) is fixedly disposed at the bottom of the internal cavity of the test section cylinder (301); the optical observation window (303) is symmetrically opened on the side wall of the test section cylinder (301), and the optical observation window (303) is sealed and fixedly disposed with the side wall of the test section cylinder (301); the sensor mounting interface is arranged in the test section cylinder (301). The outer wall of the test section cylinder (301) is connected to the inner cavity and the inner model of the test section cylinder (301). The transition section (304) is symmetrically arranged at both ends of the inner wall of the test section cylinder (301). The inlet is a circular cross section with the same inner cavity as the shock tube body (1). The outlet is a non-circular cross section that matches the inner wall cavity of the test section cylinder (301). One end of the extension pipe section (305) is connected to the test section cylinder (301), and the other end extends into the interior of the vacuum chamber (4).

5. The shock tube driven tube tunnel flow pulse direct connection test device according to claim 4, characterized in that, The measurement components include a pressure measurement subunit, a temperature measurement subunit, a flow field observation subunit, and an aerodynamic parameter acquisition subunit; The pressure measurement subunit and temperature measurement subunit are respectively sealed and fixedly connected to the test section cylinder (301) and shock tube body (1) through the sensor mounting interface; the flow field observation subunit is set in a position corresponding to the optical observation window (303); the signal acquisition end of the aerodynamic parameter acquisition subunit is electrically connected to the sensor on the scaled-down vehicle model.

6. The shock tube driven tube tunnel flow pulse direct connection test device according to claim 4, characterized in that, The second separation component (202) is installed or not installed depending on the test conditions. When the diaphragm is installed, the separation diaphragm is sealed between the drive section (102) and the transition section (304) by the diaphragm clamping flange.

7. The shock tube driven tube tunnel flow pulse direct connection test device according to claim 1, characterized in that, The vacuum chamber (4) includes a vacuum pump assembly, a chamber body, and a vacuum degree measuring instrument; The vacuum pump assembly's pumping end is connected to the cavity of the shock tube body (1) and the test section assembly (3) respectively through the vacuum valve assembly, and the vacuum degree measuring instrument's detection end is connected to each cavity respectively; The gas control assembly includes a high-pressure gas cylinder group, a vacuum pump group, a pressure regulating valve group, a gas filling valve group, a vacuum valve group, and a pressure monitoring unit; The outlet of the high-pressure gas cylinder group is connected to the driving chamber and the driven chamber of the shock tube body (1) through the pressure regulating valve group and the gas filling valve; the vacuum pump group is connected to the driving chamber and the driven chamber of the shock tube body (1) and the vacuum chamber (4) through the vacuum valve group; the detection end of the pressure monitoring unit is connected to the driving chamber, the driven chamber and the vacuum chamber (4).

8. A direct-connection test method for pipe-tunnel flow based on shock tube pulse drive, characterized in that, The shock tube driven tube-tunnel flow pulse direct connection test apparatus according to any one of claims 1 to 7 comprises the following steps: S1, reverse design of test parameters: based on the actual operating conditions of the pipe tunnel to be simulated, combined with the similarity criteria of pipe tunnel flow, determine the required airflow Mach number, pressure, and temperature parameters, and reverse design to obtain the initial operating parameters of the driving section (101) and driven section (102) of the shock tube body. S2, test preparation, fix the scaled-down aircraft model in the internal mounting position of the test section assembly (3), complete the diaphragm clamping and sealing assembly of the shock tube body (1) and the test section assembly (3), adjust the cavity of the test section (3) and the vacuum chamber (4) to the set initial vacuum degree through the gas control assembly, adjust the driven chamber of the shock tube body (1) to the required initial pressure, and fill the driven chamber of the shock tube body (1) with the set parameters of driving gas; S3, test airflow is generated, the diaphragm of the first separation component (201) ruptures, the high-pressure gas in the driving section (101) enters the driven section (102) to form an incident shock wave, and a uniform airflow with set parameters is generated in the driven section (102). S4, the flow field of the pipe tunnel is established, the incident shock wave arrives at the second separation component (202) of the test section, directly enters or causes the second diaphragm to rupture and enters the test section component (3), sweeps the scaled-down vehicle model, and establishes the pipe tunnel flow or blockage flow field corresponding to the real working conditions in the test section. S5, Test data acquisition: The airflow parameters, flow field structure parameters, and aerodynamic parameters of the scaled-down vehicle model are synchronously acquired through the measurement components during the test until the test airflow window disappears and the test ends. S6, Post-test processing: The cavity is vented and depressurized through the extended pipe section (305), the collected test data is sorted out, and the flow characteristics of the pipe tunnel are analyzed.

9. The method for direct connection test of pipe-tunnel flow based on shock tube pulse drive according to claim 8, characterized in that, In step S1, for the pipe tunnel flow condition of the choking mode, the choking airflow parameters in front of the test model are obtained by quasi-one-dimensional calculation, and the initial operating parameters of the shock tube body (1) under the direct connection test mode of the stagnation chamber are obtained by reverse design. In step S2, the driving section (101) and the driven section (102) are adjusted to a set pressure by the gas control component; In step S3, under congested flow conditions, the incident shock wave is reflected at the inlet end of the test section component (3) to form a reflected shock wave, and a high-pressure and high-temperature airflow matching the congested airflow parameters in front of the vehicle is generated at the end of the driven section (102). In step S4, under congested flow conditions, the diaphragm of the second separation component (202) ruptures, and the high-pressure airflow in the sump enters the test section component (3), establishing a fully expanded congested flow field that matches the actual working conditions.

10. The method for direct connection test of pipe-tunnel flow based on shock tube pulse drive according to claim 8, characterized in that, The reverse design of test parameters in step S1 follows the core principles of geometric similarity, Mach number similarity, and Reynolds number similarity to ensure that the blockage ratio of the scaled-down model is consistent with that of the real aircraft and that the Mach number of the test airflow is consistent with that of the real incoming flow. For high Reynolds number pipe and tunnel flow conditions, the Reynolds number similarity requirements are relaxed based on the flow self-modeling property, and the test Reynolds number is controlled to the target level by adjusting the pressure parameters of the test airflow.

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