Adjustable double-hydrofoil non-uniform incoming flow generating device

Abstract

The invention provides an adjustable double-hydrofoil non-uniform incoming flow generating device which is composed of a water tunnel connecting module, a double-hydrofoil incoming flow oscillation generator module, a driving system and a data acquisition system, and a non-uniform flow field with good symmetry can be generated through in-phase flapping of double hydrofoils. And by matching with measuring devices such as a laser Doppler velocimeter, a pressure acquisition system and a high-speed camera, adjustability and controllability of an incoming flow generation process can be maintained while multiple water tunnel tests are carried out, so that powerful support can be provided for research on complex flow mechanisms such as cavitation evolution and underwater vehicle controllability.

Description

Technical Field

[0001] This invention belongs to the technical field of fluid mechanics experimental devices, specifically relating to a controlled non-uniform flow generation device suitable for studying flow characteristics such as cavitation and supercavitation. Background Technology

[0002] Currently, many studies on fluid cavitation, supercavitation morphology evolution, and the motion characteristics of underwater vehicles are often conducted through scaled-down model experiments in the flow field. To simulate the real fluid environment and related physical phenomena in the flow field, flexible and precise control of the incoming flow generation process is required. However, most existing technologies use a single-step motor to drive a hydrofoil or propeller to generate the incoming flow under predetermined control rules. This cannot provide the diverse disturbance modes required for the experiment, and the stability of the incoming flow is easily affected by the interaction between the propeller and the water flow. Therefore, how to provide a non-uniform incoming flow generation device with flexible parameter adjustment, diverse disturbance modes, and high flow stability is an urgent technical problem to be solved in this field. Summary of the Invention

[0003] In view of this, and in response to the technical problems existing in this field, the present invention provides an adjustable dual hydrofoil non-uniform flow generator, which consists of a water tunnel connection module, a dual hydrofoil flow oscillation generator module, a drive system, and a data acquisition system.

[0004] The water tunnel connection module has a closed space to contain the fluid medium and provide the watertight environment required for the experiment. A transparent viewing window is set on part of the outer wall of the water tunnel connection module for optical measurement and visualization analysis related to the experiment. Small panels a and b are horizontally distributed on one side wall of the water tunnel connection module. Small panel a has two longitudinally distributed shaft holes for fixing and supporting the dual hydrofoil flow oscillation generator module. Small panel b is used to install the experimental model device in the watertight environment.

[0005] The dual hydrofoil inflow oscillation generator module includes two hydrofoils, hydrofoil shafts, and a rocker arm bracket. Both hydrofoils are set in a watertight environment, and each hydrofoil is fixedly connected to the end of a hydrofoil shaft. The rocker arm bracket is fixedly set outside the watertight environment of the small panel a. Each hydrofoil shaft passes through one of the shaft holes on the small panel a and is rotatably connected to the rocker arm bracket through a self-aligning bearing. The end of each hydrofoil shaft outside the watertight environment extends out of the rocker arm bracket and is fixedly connected to a rocker arm.

[0006] The drive system includes a servo motor, coupling, ball screw, slide, push-pull linkage, and drive control module. The output shaft of the servo motor is fixedly connected to the ball screw via the coupling. The slide is mounted on the ball screw and can move along the ball screw under the drive of the servo motor. One end of the push-pull linkage is fixedly connected to the slide, and it includes a main linkage and a driven linkage. The ends of the main linkage and the driven linkage are respectively connected to the end of a rocker arm via a fisheye bearing, which is used to drive the hydrofoil to swing and generate incoming flow in a watertight environment. The drive control module is used to adjust the speed and torque of the servo motor according to the test requirements to realize the control and regulation of the incoming flow generation process.

[0007] The data acquisition system includes a laser Doppler velocimeter, a pressure acquisition system, a high-speed camera, a light source, a data synchronization unit, and a data processing computer. The laser Doppler velocimeter is used to measure the fluid velocity in the watertight environment. The pressure acquisition system consists of a pulsating pressure sensor, a signal amplifier, a data acquisition unit, and a data transmission line, all mounted on the test model or at other suitable locations in the watertight environment, and is used to detect the pulsating pressure of the incoming flow. The high-speed camera is used to acquire images of the watertight environment, while the light source is used to illuminate the watertight environment. The data synchronization unit acquires the detection data from the laser Doppler velocimeter, the pressure acquisition system, and the high-speed camera and sends it to the data processing computer. The data processing computer performs comprehensive analysis of the test data based on the various detection data to generate test results and communicates with the drive control module to achieve closed-loop control of the incoming flow and the water tunnel test process.

[0008] Furthermore, the drive control module has a control command input device and a display device, which can be selected as a separate keyboard, display or integrated touch screen. It is used to set the incoming flow disturbance waveform (such as sine wave, triangle wave, square wave) according to the test requirements and generate corresponding hydrofoil drive commands based on it. At the same time, it can also display the hydrofoil swing parameters such as the current eccentricity, disturbance frequency, flapping angle, etc. during the incoming flow generation process.

[0009] Furthermore, the hydrofoil adopts a detachable and replaceable design to meet the specific inflow requirements of different tests.

[0010] Accordingly, the present invention also provides a method for simulating non-uniform inflow of adjustable dual hydrofoils using the above-mentioned device, specifically including the following steps:

[0011] S1. Complete the assembly of the device in the water tunnel test environment, so that the two hydrofoils are symmetrically set in the upstream of the water tunnel test section, and ensure that the mechanical or electrical connection of the drive system and the data acquisition system is correct; after completing the sealing of the water tunnel connection module, inject the test fluid medium into its internal space.

[0012] S2. Set the relevant parameters of the incoming flow according to the test requirements. After the flow field stabilizes, start the drive system to make the dual hydrofoils flap according to the preset parameters to generate a non-uniform incoming flow.

[0013] S3. Use the data acquisition system to collect relevant experimental data such as flow velocity, pulsating pressure, and flow field images. The data processing computer processes and analyzes the experimental data. During the process, the data processing computer monitors the flow field parameters synchronously and performs closed-loop regulation of the incoming flow generation process based on these parameters.

[0014] The adjustable dual hydrofoil non-uniform inflow generator provided by the present invention consists of a water tunnel connection module, a dual hydrofoil inflow oscillation generator module, a drive system, and a data acquisition system. It can generate a non-uniform flow field with good symmetry by performing in-phase flapping of the dual hydrofoils. With the help of measuring devices such as laser Doppler velocimeters, pressure acquisition systems, and high-speed cameras, it can maintain the adjustability and controllability of the inflow generation process while carrying out multiple water tunnel experiments. This provides strong support for the study of complex flow mechanisms, including cavitation evolution and the maneuverability of underwater vehicles. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the water tunnel connection module structure;

[0016] Figure 2 A schematic diagram of the dual hydrofoil inflow oscillation generator module;

[0017] Figure 3 This is a schematic diagram of the drive system structure;

[0018] Figure 4 This is a schematic diagram of the overall structure of the data acquisition system and device. Detailed Implementation

[0019] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] The adjustable dual-hydrofoil non-uniform flow generator provided by this invention, such as... Figure 1-4 As shown, it consists of a water tunnel connection module, a dual hydrofoil inflow oscillation generator module, a drive system, and a data acquisition system;

[0021] The water tunnel connection module has a closed space to contain the fluid medium and provide the watertight environment required for the experiment. A transparent viewing window 1.3 is provided on part of the outer wall of the water tunnel connection module, such as the top or one side, for optical measurements and visualization analysis related to the experiment. Two horizontally distributed small panels a1.1 and b1.2 are provided on one side wall of the water tunnel connection module. Two longitudinally distributed axial holes are provided on small panel a1.1 for fixing and supporting the dual hydrofoil flow oscillation generator module. Small panel b1.2 is used to install the experimental model device in the watertight environment.

[0022] The dual hydrofoil inflow oscillation generator module includes two hydrofoils 2.1, hydrofoil shafts 2.2, and a rocker arm bracket 2.3. Both hydrofoils 2.1 are set in a watertight environment, and each hydrofoil 2.1 is fixedly connected to the end of a hydrofoil shaft 2.2. The rocker arm bracket 2.3 is fixedly set outside the watertight environment of the small panel a1.1. Each hydrofoil shaft 2.2 passes through one of the shaft holes on the small panel a1.1 and is rotatably connected to the rocker arm bracket 2.3 through a self-aligning bearing 2.4. The end of each hydrofoil shaft 2.2 outside the watertight environment extends out of the rocker arm bracket 2.3 and is fixedly connected to a rocker arm.

[0023] The drive system includes a servo motor 3.1, a coupling 3.2, a ball screw 3.3, a slide table, a push-pull linkage 3.4, and a drive control module 3.6. The output shaft of the servo motor 3.1 is fixedly connected to the ball screw 3.3 via the coupling 3.2. The slide table is mounted on the ball screw 3.3 and can move along the ball screw 3.3 under the drive of the servo motor 3.1. One end of the push-pull linkage 3.3 is fixedly connected to the slide table. It includes a main linkage and a driven linkage. The ends of the main linkage and the driven linkage are respectively connected to the end of a rocker arm via a fisheye bearing, which is used to drive the hydrofoil 2.1 to swing and generate incoming flow in a watertight environment. The drive control module 3.6 is used to adjust the speed and torque of the servo motor 3.1 according to the test requirements to realize the control and adjustment of the incoming flow generation process.

[0024] The data acquisition system includes a laser Doppler velocimeter 4.1, a pressure acquisition system, a high-speed camera 4.3, a light source 4.2, a data synchronization unit, and a data processing computer 4.5. The laser Doppler velocimeter 4.1 is used to measure the fluid velocity in the watertight environment. The pressure acquisition system consists of a pulsating pressure sensor 4.4 installed on the test model or in other suitable locations in the watertight environment, along with a signal amplifier, an acquisition unit, and a data transmission line, used to detect the pulsating pressure of the incoming flow. The high-speed camera 4.3 is used to acquire images of the watertight environment, and the light source 4.2 is used to illuminate the watertight environment; an LED surface light source can be specifically selected. The data synchronization unit is used to acquire the detection data from the laser Doppler velocimeter 4.1, the pressure acquisition system, and the high-speed camera 4.3 and send it to the data processing computer 4.5. The data processing computer 4.5 is used to perform comprehensive analysis of the test data based on the various detection data, generate experimental results such as the distribution of flow field parameters, pressure fluctuation curves, and cavitation evolution laws, and communicates with the drive control module 3.6 to achieve closed-loop control of the incoming flow generation and the water tunnel test process.

[0025] In a preferred embodiment of the present invention, the drive control module 3.6 has a control command input device and a display device, which can be selected as a separate keyboard, display or integrated touch screen, for setting the incoming flow disturbance waveform (such as sine wave, triangle wave, square wave) according to the test requirements and generating corresponding hydrofoil drive commands based on it. At the same time, it can also display the hydrofoil swing parameters such as the current eccentricity, disturbance frequency, flapping angle, etc. during the incoming flow generation process.

[0026] In a preferred embodiment of the present invention, the hydrofoil 2.1 is designed to be detachable and replaceable to meet the specific inflow requirements of different tests.

[0027] Accordingly, the present invention also provides a method for simulating non-uniform inflow of adjustable dual hydrofoils using the above-mentioned device, specifically including the following steps:

[0028] S1. Complete the assembly of the device in the water tunnel test environment, so that the two hydrofoils are symmetrically set in the upstream of the water tunnel test section, and ensure that the mechanical or electrical connection of the drive system and the data acquisition system is correct; after completing the sealing of the water tunnel connection module, inject the test fluid medium into its internal space.

[0029] S2. Set the relevant parameters of the incoming flow according to the test requirements. After the flow field stabilizes, start the drive system to make the dual hydrofoils flap according to the preset parameters to generate a non-uniform incoming flow.

[0030] S3. Use the data acquisition system to collect relevant experimental data such as flow velocity, pulsating pressure, and flow field images. The data processing computer processes and analyzes the experimental data. During the process, the data processing computer monitors the flow field parameters synchronously and performs closed-loop regulation of the incoming flow generation process based on these parameters.

[0031] It should be understood that the sequence number of each step in the embodiments of the present invention does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0032] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An adjustable dual-hydrofoil non-uniform flow generator, characterized in that: It consists of a water tunnel connection module, a dual hydrofoil inflow oscillation generator module, a drive system, and a data acquisition system; The water tunnel connection module has a closed space to contain the fluid medium and provide the watertight environment required for the experiment. A transparent viewing window is set on part of the outer wall of the water tunnel connection module for optical measurement and visualization analysis related to the experiment. Small panels a and b are horizontally distributed on one side wall of the water tunnel connection module. Small panel a has two longitudinally distributed shaft holes for fixing and supporting the dual hydrofoil flow oscillation generator module. Small panel b is used to install the experimental model device in the watertight environment. The dual hydrofoil inflow oscillation generator module includes two hydrofoils, hydrofoil shafts, and a rocker arm bracket. Both hydrofoils are set in a watertight environment, and each hydrofoil is fixedly connected to the end of a hydrofoil shaft. The rocker arm bracket is fixedly set outside the watertight environment of the small panel a. Each hydrofoil shaft passes through one of the shaft holes on the small panel a and is rotatably connected to the rocker arm bracket through a self-aligning bearing. The end of each hydrofoil shaft outside the watertight environment extends out of the rocker arm bracket and is fixedly connected to a rocker arm. The drive system includes a servo motor, coupling, ball screw, slide, push-pull linkage, and drive control module. The output shaft of the servo motor is fixedly connected to the ball screw via the coupling. The slide is mounted on the ball screw and can move along the ball screw under the drive of the servo motor. One end of the push-pull linkage is fixedly connected to the slide, and it includes a main linkage and a driven linkage. The ends of the main linkage and the driven linkage are respectively connected to the end of a rocker arm via a fisheye bearing, which is used to drive the hydrofoil to swing and generate incoming flow in a watertight environment. The drive control module is used to adjust the speed and torque of the servo motor according to the test requirements to realize the control and regulation of the incoming flow generation process. The data acquisition system includes a laser Doppler velocimeter, a pressure acquisition system, a high-speed camera, a light source, a data synchronization unit, and a data processing computer. The laser Doppler velocimeter is used to measure the fluid velocity in the watertight environment. The pressure acquisition system consists of a pulsating pressure sensor, a signal amplifier, a data acquisition unit, and a data transmission line, all installed on the test model or at other suitable locations in the watertight environment, and is used to detect the pulsating pressure of the incoming flow. The high-speed camera is used to acquire images of the watertight environment, and the light source is used to illuminate the watertight environment. The data synchronization unit acquires the detection data from the laser Doppler velocimeter, the pressure acquisition system, and the high-speed camera and sends it to the data processing computer. The data processing computer performs comprehensive analysis of the test data based on the various detection data to generate test results and communicates with the drive control module to achieve closed-loop control of the incoming flow and the water tunnel test process.

2. The apparatus as described in claim 1, characterized in that: The drive control module has a control command input device and a display device. It can be selected from a separate keyboard, monitor or integrated touch screen. It is used to set the incoming flow disturbance waveform according to the test requirements and generate corresponding hydrofoil drive commands based on it. At the same time, it can also display the hydrofoil swing parameters during the incoming flow generation process.

3. The apparatus as described in claim 1, characterized in that: The hydrofoil features a detachable and replaceable design to meet the specific inflow requirements of different tests.

4. A method for simulating non-uniform inflow using an adjustable dual hydrofoil employing the apparatus described in any one of claims 1-3, characterized in that: Specifically, the following steps are included: S1. Complete the assembly of the device in the water tunnel test environment, so that the two hydrofoils are symmetrically set in the upstream of the water tunnel test section, and ensure that the mechanical or electrical connection of the drive system and the data acquisition system is correct; after completing the sealing of the water tunnel connection module, inject the test fluid medium into its internal space. S2. Set the relevant parameters of the incoming flow according to the test requirements. After the flow field stabilizes, start the drive system to make the dual hydrofoils flap according to the preset parameters to generate a non-uniform incoming flow. S3. Use the data acquisition system to collect relevant experimental data such as flow velocity, pulsating pressure, and flow field images. The data processing computer processes and analyzes the experimental data. During the process, the data processing computer monitors the flow field parameters synchronously and performs closed-loop regulation of the incoming flow generation process based on these parameters.

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