A jet interference force test method and device for a wind tunnel and a storage medium

Abstract

This specification provides a method, apparatus, and storage medium for measuring jet interference force in a wind tunnel. The method includes: pre-setting the angle of attack or sideslip angle of the wind tunnel test model; turning on the ejector and main air source to conduct a jetless test and obtain jet-free jet dynamics data; further turning on the jet flow and conducting a jet-flow test to obtain jet-flow dynamics data; turning off the main air source, returning the angle of attack or sideslip angle to zero, conducting a nozzle thrust calibration test, setting the ejector working time to not exceed a preset value, and obtaining nozzle thrust calibration data; and obtaining a jet aerodynamic interference factor based on the jetless jet dynamics data, the jet-flow dynamics data, and the nozzle thrust calibration data. This allows for three types of tests—jet-flow, jetless, and nozzle thrust calibration—during the same wind tunnel operation, ultimately obtaining the jet aerodynamic interference factor, improving test efficiency, and making the test faster and simpler.

Description

Technical Field

[0001] This document relates to the field of wind tunnel testing methods, and in particular to a method, apparatus and storage medium for force measurement of jet interference in a wind tunnel. Background Technology

[0002] The jet aerodynamic interference factor is used to quantify the degree of influence of the jet on the dynamic characteristics of an aircraft. By calculating and analyzing the jet aerodynamic interference factor, the impact of the jet on the aircraft performance can be predicted and evaluated more accurately.

[0003] Existing technologies require conducting experiments in two wind tunnel environments using both direct and indirect force measurement methods to obtain jet flow and thrust data when determining the jet flow aerodynamic factors.

[0004] However, existing technologies require testing in two wind tunnel environments, which is quite cumbersome. Furthermore, existing thrust data is obtained by using a vacuum pump in the wind tunnel. Since the environmental back pressure fluctuates greatly after the jet is activated, and the environmental back pressure rises rapidly after a large number of jets are activated, it is impossible to stabilize the required back pressure environment. This results in large fluctuations in the nozzle thrust calibration data, which in turn affects the accuracy of the jet interference factor. Summary of the Invention

[0005] In view of the above solutions, this application aims to provide a method, apparatus and storage medium for force measurement of jet interference in wind tunnels, so as to solve at least one of the above technical problems.

[0006] Firstly, one or more embodiments of this specification provide a method for force measurement of jet interference in a wind tunnel, including:

[0007] The angle of attack or sideslip angle of the wind tunnel test model is set in advance, the ejector and main air source are turned on, and a jetless test is conducted to obtain jetless jet dynamic data.

[0008] Further activate the jet stream and conduct a jet test to obtain jet propulsion data.

[0009] Shut down the main air supply, return the angle of attack or sideslip angle to zero, perform a nozzle thrust calibration test, set the ejector working time to not exceed a preset value, and obtain nozzle thrust calibration data; and

[0010] Based on the jet-free aerodynamic data, the jet-with-jet aerodynamic data, and the nozzle thrust calibration data, the jet aerodynamic interference factor is obtained.

[0011] Furthermore, wind tunnel tests were conducted using an ejector-type transient wind tunnel.

[0012] Furthermore, the nozzle in the wind tunnel test model is connected to the wind tunnel test model in a fixed integrated manner.

[0013] Furthermore, in both the no-spray test and the sprayed test, the preset angle of attack or preset sideslip angle sequence is the same.

[0014] Furthermore, the formula for calculating the jet aerodynamic interference factor is as follows:

[0015] K i =(C i有喷 -C i无喷 ) / C i喷流

[0016] Among them, K i Indicates the jet aerodynamic interference factor;

[0017] C i有喷 This indicates that jet propulsion data is available;

[0018] C i无喷 This indicates that there is no jet propulsion data; and

[0019] C i喷流 This indicates the nozzle thrust calibration data.

[0020] Secondly, embodiments of this application provide a force measurement device for jet interference in a wind tunnel, comprising:

[0021] The jetless test module is used to pre-set the angle of attack or sideslip angle of the wind tunnel test model, turn on the ejector and main air source, conduct jetless tests, and obtain jetless jet dynamic data.

[0022] The jet test module is used to further open the jet stream, conduct jet tests, and obtain jet propulsion data;

[0023] The nozzle thrust calibration test module is used to shut off the main air source, return the angle of attack or sideslip angle to zero, conduct a nozzle thrust calibration test, and obtain nozzle thrust calibration data; and

[0024] The calculation module is used to obtain the jet aerodynamic interference factor based on the jet-free aerodynamic data, the jet-with-jet aerodynamic data, and the nozzle thrust calibration data.

[0025] Furthermore, wind tunnel tests were conducted using an ejector-type transient wind tunnel.

[0026] Furthermore, the nozzle in the wind tunnel test model is connected to the wind tunnel test model in a fixed integrated manner.

[0027] Furthermore, in both the no-spray test and the sprayed test, the preset angle of attack or preset sideslip angle sequence is the same.

[0028] Thirdly, embodiments of this application provide a storage medium for storing computer-executable instructions, characterized in that, when executed, the computer-executable instructions implement the steps of the wind tunnel jet interference force measurement test method described in any one of the first aspects.

[0029] Compared with the prior art, this application can achieve at least the following technical effects:

[0030] This application enables the completion of nozzle thrust calibration tests without jetting, with jetting, and with jetting in the same wind tunnel test, obtaining the nozzle thrust data, jet-without jetting data, and jetting data required for calculating the aerodynamic interference factor in one go, thereby simplifying the test process; obtaining nozzle thrust calibration data under ejector-opening conditions is achieved by using the ejector to extract a relatively low pressure from the wind tunnel, stabilizing the environmental back pressure, thereby obtaining more reliable nozzle thrust and improving the accuracy of the jet aerodynamic interference factor. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in one or more embodiments of this specification or in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 A flowchart of a wind tunnel jet interference force measurement test method provided for one or more embodiments of this specification;

[0033] Figure 2 This is a schematic diagram of a wind tunnel jet interference force measurement device provided for one or more embodiments of this specification. Detailed Implementation

[0034] To enable those skilled in the art to better understand the technical solutions in one or more embodiments of this specification, the technical solutions in one or more embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this specification, and not all of the embodiments. Based on one or more embodiments of this specification, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this document.

[0035] When conducting wind tunnel tests on aircraft, nozzle thrust calibration tests, no-jet tests, and jet-jet tests need to be completed in two environments. The test workload is cumbersome. Moreover, under the condition of vacuum pump evacuation, the ambient back pressure fluctuates greatly after the jet is turned on. After the high-flow jet is turned on, the ambient back pressure rises rapidly and cannot be stabilized at the required ambient back pressure conditions. This causes certain fluctuations in the jet of the nozzle thrust calibration results, which is not conducive to the subsequent processing and analysis of aerodynamic interference data.

[0036] Example 1

[0037] To address the aforementioned technical problems, this application proposes a method for force measurement of jet interference in wind tunnels, such as... Figure 1 As shown, the specific steps are as follows:

[0038] Step S1: Pre-set the angle of attack or sideslip angle of the wind tunnel test model, turn on the ejector and main air source, conduct a jetless test, and obtain jetless dynamic data.

[0039] In this embodiment, before the wind tunnel test, the angle of attack, sideslip angle, total incoming pressure, and total temperature of the wind tunnel test model are precisely set according to the test objectives and requirements. For example, the angle of attack is adjusted from 0 degrees to 20 degrees in increments of 2 degrees. The wind tunnel test model is fixed within the test section, and the model's attitude is precisely adjusted using an angle of attack mechanism to ensure it can change at the preset angle. All measuring equipment (such as force balances and pressure sensors) is calibrated and connected to the data acquisition system. The ejector is then checked to confirm it is in good working order and that the nozzle and other critical components are not damaged or blocked. Once the wind tunnel test model and measuring equipment have been debugged, the wind tunnel is run according to the specified test conditions after entering the wind tunnel test procedure.

[0040] First, by activating the ejector, the pressure inside the test chamber is gradually reduced to a predetermined value (e.g., simulating the low-pressure environment required for high-altitude conditions). The ejector relies on the high-speed airflow created by the high-pressure fluid passing through the nozzle to generate a powerful driving force, thereby driving the airflow within the wind tunnel. Furthermore, the ejector can operate continuously within the wind tunnel or test chamber to maintain the required low-pressure environment. This helps simulate the real-world environment of an aircraft during high-altitude flight, enabling more accurate testing and evaluation.

[0041] Secondly, once the test chamber pressure reaches the predetermined value, the main air source is activated to establish the incoming flow field. Predetermined pressure, temperature, and other operating parameters are set for the main air source to simulate atmospheric conditions at different altitudes and environments during flight. This ensures that the gas supplied by the main air source can stably enter the wind tunnel test section, forming a uniform incoming flow field to meet the required speed and density conditions for the test. The main air source is the core component of wind tunnel testing, responsible for providing stable and continuous airflow. It can also adjust airflow parameters such as airflow velocity, pressure, and temperature according to test requirements. In wind tunnel testing, it plays a crucial role in providing stable airflow, adjusting airflow parameters, supporting the operation of test equipment, and ensuring test safety.

[0042] Finally, under these conditions, jetless tests were conducted, and the angle of attack or sideslip angle of the wind tunnel test model was tested one by one. After each adjustment, jetless aerodynamic data was recorded. The jetless aerodynamic data refers to the aerodynamic characteristics of the model, such as lift, drag, and torque, under the condition of incoming flow without jet flow.

[0043] Step S2: Further activate the jet stream and conduct a jet test to obtain jet propulsion data.

[0044] In this embodiment, after completing the jetless test, the jet is further activated after the ejector and main air source are turned on. The flow rate, velocity, and direction of the jet are adjusted according to test requirements. A jetted test is then conducted, measuring the angle of attack or sideslip angle of the wind tunnel model one by one. Jet aerodynamic data is recorded after each adjustment. The jet aerodynamic data includes the aerodynamic characteristics of the model, such as lift, drag, and torque, under the influence of the jet. The jet can simulate the airflow effect generated by the engine during actual flight. Wind tunnel testing can determine the interference of the jet on the external flow of the aircraft, thereby fully utilizing the beneficial interference of the jet, rationally arranging the aircraft components, reducing drag, and improving the aircraft's handling and stability. It can also determine the interference of the external flow on the jet, thereby rationally arranging the engine and nozzle positions, selecting the optimal nozzle type and size to obtain the engine's maximum thrust. Furthermore, by comparing the jet-affected and jetless wind tunnel tests, data on the impact of the jet is obtained to ensure the accuracy of the flight data.

[0045] Step S3: Turn off the main gas source, return the angle of attack or sideslip angle to zero, perform a nozzle thrust calibration test, set the ejector working time to not exceed a preset value, and obtain nozzle thrust calibration data.

[0046] In this embodiment, after completing the injection test, the main air source is shut off while the ejector and jet are activated, thereby eliminating interference from the incoming airflow on the nozzle thrust measurement. The model's angle of attack or sideslip angle is then adjusted back to zero to ensure the thrust measurement is performed under conditions of no tilting and no lateral force. A nozzle thrust calibration test is then conducted. During the nozzle thrust calibration process, the wind tunnel ejector is kept operational for at least 5 seconds to prevent insufficient effective values ​​from affecting the test results. A thrust meter and other measuring equipment are then used to accurately record the thrust value of the nozzle during the injection process. The nozzle and the wind tunnel test model are connected in a fixed, integrated manner to ensure that the force balance can directly and in real-time measure the nozzle thrust calibration data, ensuring the accuracy and completeness of the data. The nozzle thrust calibration data refers to data obtained through experiments or simulations under specific conditions regarding the relationship between the thrust generated by the nozzle and its operating parameters, such as total thrust, thrust coefficient, combustion chamber pressure, and nozzle exit pressure.

[0047] Step S4: Based on the jet-free aerodynamic data, the jet-with-jet aerodynamic data, and the nozzle thrust calibration data, obtain the jet aerodynamic interference factor.

[0048] In this embodiment, the same aerodynamic characteristic data needs to be measured and recorded during both the no-jet and jet-propelled tests. Using the same aerodynamic characteristic data, the difference between the measured values ​​of jet-propelled data under jet-propelled conditions and jet-free data under no-jet conditions is calculated to obtain the change data caused by the jet flow. The change caused by the jet flow is then compared with the thrust value of the nozzle to evaluate the relative impact of the jet flow on aerodynamic performance, thereby obtaining the jet flow aerodynamic interference factor.

[0049] Using the same angle of attack or sideslip angle sequence in this application ensures that these parameters are measured under the same conditions, which facilitates subsequent comparison and analysis.

[0050] Preferably, the wind tunnel test is conducted using an ejector-type transient wind tunnel.

[0051] Ejector-type supersonic wind tunnels refer to supersonic wind tunnels with ejector functions. Using a supersonic wind tunnel with ejector functions, even after the main air source is shut off, the ejector and jet are still open, allowing for nozzle thrust calibration tests. The ejector can be used to extract a relatively low pressure into the wind tunnel for a certain period of time, thereby obtaining the thrust data of the jet itself when the jet is open, i.e., the nozzle thrust calibration data.

[0052] In an ejector-type transient wind tunnel, the main air source, ejector, and jet stream components can work in sequence according to the experimental order. This allows the wind tunnel test to complete the jetless test, the jet-driven test, and the nozzle thrust calibration test sequentially in a single wind tunnel run. This provides a complete set of data, including jetless jet propulsion data, jet propulsion data, and nozzle thrust calibration data, all measured in one go. Their synergistic effect enables the wind tunnel to simulate various complex airflow conditions, thus meeting the design and optimization requirements of aircraft.

[0053] For example: The test model is fixed within the wind tunnel test section, ensuring its stability and ability to freely adjust its attitude. Then, the wind tunnel test model is assembled on the ground, connecting components such as a force balance, sensors, and support rods. Next, calibration instruments are used to calibrate the model and testing equipment, ensuring all measuring devices are calibrated and connected to the data acquisition system, ready to record experimental data. First, the ejector control valve is opened, gradually reducing the pressure inside the test chamber to a predetermined value. Once the pressure reaches the predetermined value, the main air source is activated, setting the predetermined pressure, temperature, and other operating parameters (e.g., 30 bar pressure and 300 K temperature). This ensures that the gas supplied by the main air source can stably enter the wind tunnel test section, forming a uniform inflow field that meets the required velocity and density conditions for the test. Second, a jetless test is conducted, gradually increasing the angle of attack or sideslip angle according to a predetermined sequence. After each adjustment, sufficient time is allowed for the airflow to stabilize, and then the corresponding aerodynamic parameters are recorded. For each angle point, multiple independent measurements are performed to ensure data consistency and reliability. Next, conduct a jet-powered test, gradually starting the jet air source to ensure a smooth transition and reaching the predetermined operating state. Under jet conditions, retest the angle of attack or sideslip angle and record the corresponding data. Then, conduct a nozzle thrust calibration test, gradually shutting off the main air source to ensure a smooth transition and avoid sudden air supply interruptions that could impact the system. Adjust the model's angle of attack and sideslip angle back to 0 degrees to ensure the model returns to its initial attitude. Keep the ejector operational for at least a preset time (e.g., 5 seconds), while simultaneously recording the thrust data generated by the nozzle. This thrust data will provide more effective values ​​when averaging later, improving the accuracy of the test. Finally, combine the jet-powered and jet-less jet-powered data from the same sequence with the nozzle thrust calibration data to calculate the jet aerodynamic interference factor and evaluate the jet's impact on aircraft performance.

[0054] Preferably, the preset angle of attack or preset sideslip angle sequence is the same in both the no-spray test and the sprayed test.

[0055] Angle of attack and sideslip angle are the tilt angles of an aircraft model relative to the direction of incoming flow. Maintaining the same sequence of angles of attack or sideslip angles in both jet-free and jet-powered tests ensures that the aerodynamic performance of the model is measured at the same attitude and angle under both conditions, thus eliminating the interference of attitude changes on aerodynamic performance evaluation. In addition to angles of attack or sideslip angles, it is also necessary to ensure that conditions such as incoming flow velocity, temperature, and pressure remain consistent in both jet-free and jet-powered tests to further guarantee the consistency of test conditions.

[0056] For example, a series of angles of attack are set, such as 0°, 5°, 10°, 15°, and 20°. In jetless experiments, the model's attitude is adjusted according to this angle-of-attack sequence, and the corresponding jetless aerodynamic data is measured. In jetted experiments, the model's attitude is adjusted according to the same angle-of-attack sequence, the jet is activated, and jetted aerodynamic data is measured. The jetless and jetted aerodynamic data include key aerodynamic performance parameters such as lift, drag, and lateral force. By comparing the aerodynamic data from jetless and jetted experiments, the impact of the jet on the model's aerodynamic performance is evaluated, and the trends and patterns of the jet's influence on the model's aerodynamic performance at different angles of attack are analyzed.

[0057] Preferably, the formula for calculating the jet aerodynamic interference factor is as follows:

[0058] K i =(C i有喷 -C i无喷 ) / C i喷流

[0059] Among them, K i Indicates the jet aerodynamic interference factor;

[0060] C i有喷 This indicates that jet propulsion data is available;

[0061] C i无喷 This indicates that there is no jet propulsion data; and

[0062] C i喷流 This indicates the nozzle thrust calibration data.

[0063] Example 2

[0064] To study the aerodynamic effects of aircraft jet interference through wind tunnel testing and obtain the jet interference aerodynamic interference factor, a jet interference force measurement test method suitable for pressure ejection operation wind tunnels was established. The specific steps are as follows:

[0065] (1) Assemble the wind tunnel test model, force balance, support rod and other components on the ground, and install the wind tunnel support rod on the wind tunnel angle of attack mechanism;

[0066] (2) After the model and test system are debugged, prepare to enter the wind tunnel test process;

[0067] (3) Turn on the ejector. After the pressure in the test chamber drops to about 6000 Pa, turn on the main gas source and establish the incoming flow field with predetermined parameters.

[0068] (4) Keep the jet air source in the off state and complete the jetless blowing test under the attack angle sequence conditions of α=-4°, -2°, 0°, 2°, 4°, and obtain the jetless jet dynamic data C under each attack angle condition. i无喷 ;

[0069] (5) Turn on the jet air source and adjust the total jet pressure P 0j =1.0MPa, complete the jet blowing test under the conditions of α = -4°, -2°, 0°, 2°, 4° angle of attack sequence, and obtain the jet dynamics data C under each angle of attack condition. i有喷 ;

[0070] (6) After completing the blasting test of this angle of attack sequence, return the angle of attack to zero and maintain the total pressure P of the jet opening. 0j =1.0MPa, shut off the main air supply to the wind tunnel, and keep the wind tunnel ejector running. At this time, the pressure in the test chamber is about 6000Pa, completing P. 0j The nozzle thrust calibration test was conducted under a total pressure of 1.0 MPa, and the nozzle thrust calibration data C was obtained. i喷流 ;

[0071] (7) Turn off the ejector and complete the wind tunnel test;

[0072] (8) Obtain the jet aerodynamic interference factor K under various angles of attack conditions. i =(C i有喷 -C i无喷 ) / C i喷流 .

[0073] Using the method of this application, nozzle thrust calibration tests with and without jet propulsion can be completed in a single blower run, obtaining the nozzle thrust data, jet-without jet propulsion data, and jet propulsion data required for calculating the aerodynamic interference factor in one go. This facilitates the implementation of tests using direct force measurement of jet interference. In the nozzle thrust calibration test, the nozzle thrust calibration data is measured under ejector-open conditions, where the environmental back pressure is relatively stable, which is beneficial for obtaining more reliable nozzle thrust.

[0074] Example 3

[0075] This application provides a wind tunnel jet interference force measurement test device, such as... Figure 2 As shown, it includes:

[0076] The jetless test module 101 is used to pre-set the angle of attack or sideslip angle of the wind tunnel test model, turn on the ejector and main air source, conduct a jetless test, and obtain jetless jet dynamic data.

[0077] The jet test module 102 is used to further open the jet flow, conduct a jet test, and obtain jet dynamic data.

[0078] The nozzle thrust calibration test module 103 is used to shut down the main air source, return the angle of attack or sideslip angle to zero, conduct a nozzle thrust calibration test, and obtain nozzle thrust calibration data; and

[0079] The calculation module 104 is used to obtain the jet aerodynamic interference factor based on the jet-free aerodynamic data, the jet-without aerodynamic data, and the nozzle thrust calibration data.

[0080] Furthermore, wind tunnel tests were conducted using an ejector-type transient wind tunnel.

[0081] Furthermore, the nozzle in the wind tunnel test model is connected to the wind tunnel test model in a fixed integrated manner.

[0082] Furthermore, in both the no-spray test and the sprayed test, the preset angle of attack or preset sideslip angle sequence is the same.

[0083] This application provides a storage medium for storing computer-executable instructions, characterized in that, when executed, the computer-executable instructions implement the steps of the wind tunnel jet interference force measurement test method described in any of the above embodiments.

[0084] It should be noted that the embodiments concerning storage media in this specification and the embodiments concerning blockchain-based service provision methods in this specification are based on the same inventive concept. Therefore, the specific implementation of this embodiment can be referred to the implementation of the corresponding blockchain-based service provision method described above, and the repeated parts will not be described again.

[0085] The foregoing has described specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.

[0086] In the 1930s, improvements to a technology could be clearly distinguished as either hardware improvements (e.g., improvements to the circuit structure of diodes, transistors, switches, etc.) or software improvements (improvements to the methodology). However, with technological advancements, many improvements to the methodology today can be considered direct improvements to the hardware circuit structure. Designers almost always obtain the corresponding hardware circuit structure by programming the improved methodology into the hardware circuit. Therefore, it cannot be said that an improvement to the methodology cannot be implemented using a hardware physical module. For example, a Programmable Logic Device (PLD) (e.g., a Field Programmable Gate Array (FPGA)) is such an integrated circuit whose logic function is determined by the user programming the device. Designers can program a digital system themselves to "integrate" it onto a PLD, without needing chip manufacturers to design and manufacture dedicated integrated circuit chips. Furthermore, nowadays, instead of manually manufacturing integrated circuit chips, this programming is mostly implemented using "logic compiler" software. Similar to the software compiler used in program development, the original code before compilation must be written in a specific programming language, called a Hardware Description Language (HDL). There are many HDLs, such as ABEL (Advanced Boolean Expression Language), AHDL (Altera Hardware Description Language), Confluence, CUPL (Cornell University Programming Language), HDCal, JHDL (Java Hardware Description Language), Lava, Lola, MyHDL, PALASM, and RHDL (Ruby Hardware Description Language). Currently, the most commonly used are VHDL (Very-High-Speed ​​Integrated Circuit Hardware Description Language) and Verilog. Those skilled in the art should understand that by simply performing some logic programming on the method flow using one of these hardware description languages ​​and programming it into an integrated circuit, the hardware circuit implementing the logical method flow can be easily obtained.

[0087] The controller can be implemented in any suitable manner. For example, it can take the form of a microprocessor or processor and a computer-readable medium storing computer-readable program code (e.g., software or firmware) executable by the (micro)processor, logic gates, switches, application-specific integrated circuits (ASICs), programmable logic controllers, and embedded microcontrollers. Examples of controllers include, but are not limited to, the following microcontrollers: ARC 625D, Atmel AT91SAM, Microchip PIC18F26K20, and Silicon Labs C8051F320. A memory controller can also be implemented as part of the control logic of the memory. Those skilled in the art will also recognize that, in addition to implementing the controller in purely computer-readable program code form, the same functionality can be achieved by logically programming the method steps to make the controller take the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers. Therefore, such a controller can be considered a hardware component, and the means included therein for implementing various functions can also be considered as structures within the hardware component. Alternatively, the means for implementing various functions can be considered as both software modules implementing the method and structures within the hardware component.

[0088] The systems, devices, modules, or units described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer. Specifically, a computer can be, for example, a personal computer, laptop computer, cellular phone, camera phone, smartphone, personal digital assistant, media player, navigation device, email device, game console, tablet computer, wearable device, or any combination of these devices.

[0089] For ease of description, the above apparatus is described by dividing it into various functional units. Of course, when implementing the embodiments of this specification, the functions of each unit can be implemented in one or more software and / or hardware.

[0090] Those skilled in the art will understand that one or more embodiments of this specification can be provided as a method, system, or computer program product. Therefore, one or more embodiments of this specification may take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this specification may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0091] This specification is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this specification. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0092] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0093] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0094] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0095] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0096] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0097] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0098] One or more embodiments of this specification can be described in the general context of computer-executable instructions, such as program modules, that are executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform a particular task or implement a particular abstract data type. One or more embodiments of this specification can also be practiced in distributed computing environments where tasks are performed by remote processing devices connected via a communication network. In distributed computing environments, program modules can reside in local and remote computer storage media, including storage devices.

[0099] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0100] The above description is merely an embodiment of this document and is not intended to limit the scope of this document. Various modifications and variations can be made to this document by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this document should be included within the scope of the claims of this document.

Claims

1. A method for force measurement of jet interference in a wind tunnel, characterized in that... include: The angle of attack or sideslip angle of the wind tunnel test model is preset, the ejector and main air source are turned on, and a jetless test is conducted to obtain jetless jet propulsion data. First, the pressure in the test chamber is gradually reduced to a predetermined value by turning on the ejector. Second, when the pressure in the test chamber reaches the predetermined value, the main air source is turned on to establish the incoming flow field. The predetermined pressure, temperature and operating parameters of the main air source are set to simulate atmospheric conditions at different altitudes and in different environments during flight. Finally, under these conditions, a jetless test is conducted, and the angle of attack or sideslip angle of the wind tunnel test model is tested one by one. After each adjustment, the jetless jet propulsion data is recorded. Further activate the jet stream and conduct a jet test to obtain jet propulsion data; after completing the jetless test, activate the jet stream again based on the activation of the ejector and main air source, and adjust the flow rate, velocity and direction of the jet stream according to the test requirements; conduct a jet test to test the angle of attack or sideslip angle of the wind tunnel test model one by one, and record the jet propulsion data after each adjustment; Turn off the main air source, return the angle of attack or sideslip angle to zero, conduct a nozzle thrust calibration test, set the ejector working time to not exceed a preset value, and obtain nozzle thrust calibration data; with the ejector and jet flow turned on, turn off the main air source to eliminate the interference of incoming air flow on nozzle thrust measurement, and adjust the model's angle of attack or sideslip angle back to zero. Based on the jet-free aerodynamic data, the jet-with-jet aerodynamic data, and the nozzle thrust calibration data, the jet aerodynamic interference factor is obtained; in the same wind tunnel test, using the same aerodynamic characteristic data, the difference between the measured values ​​of the jet-with-jet data under the jet-with-jet condition and the jet-free aerodynamic data under the jet-free condition is calculated to obtain the change data caused by the jet.

2. The method according to claim 1, characterized in that, The wind tunnel test was completed using an ejector-type transient wind tunnel.

3. The method according to claim 2, characterized in that... It also includes, The nozzle in the wind tunnel test model is connected to the wind tunnel test model in a fixed integrated manner.

4. The method according to claim 1, characterized in that... It also includes, In both the no-spray test and the sprayed test, the preset angle of attack or preset sideslip angle sequence is the same.

5. The method according to claim 1, characterized in that, The formula for calculating the jet aerodynamic interference factor is as follows: K i =(C i有喷 -C i无喷 ) / C i喷流 Among them, K i Indicates the jet aerodynamic interference factor; C i有喷 This indicates that jet propulsion data is available; C i无喷 This indicates that there is no jet propulsion data; and C i喷流 This indicates the nozzle thrust calibration data.

6. A force measurement device for jet interference in a wind tunnel, characterized in that... include: The jetless test module is used to pre-set the angle of attack or sideslip angle of the wind tunnel test model, activate the ejector and main air source, conduct jetless tests, and obtain jetless jet propulsion data. First, by activating the ejector, the pressure inside the test chamber is gradually reduced to a predetermined value. Second, when the pressure in the test chamber reaches the predetermined value, the main air source is activated to establish the incoming flow field. Predetermined pressure, temperature, and operating parameters are set for the main air source to simulate atmospheric conditions at different altitudes and in different environments during flight. Finally, under these conditions, jetless tests are conducted, and the angle of attack or sideslip angle of the wind tunnel test model is tested one by one. Jetless jet propulsion data is recorded after each adjustment. The jet test module is used to further open the jet stream and conduct jet tests to obtain jet propulsion data. After completing the jetless test, the jet stream is further opened based on the opening of the ejector and main air source. The flow rate, velocity and direction of the jet stream are adjusted according to the test requirements. The jet test is conducted to test the angle of attack or sideslip angle of the wind tunnel test model one by one. The jet propulsion data is recorded after each adjustment. The nozzle thrust calibration test module is used to shut down the main air source, return the angle of attack or sideslip angle to zero, conduct a nozzle thrust calibration test, and obtain nozzle thrust calibration data; with the ejector and jet flow turned on, the main air source is shut down to eliminate the interference of incoming air flow on nozzle thrust measurement, and the angle of attack or sideslip angle of the model is adjusted back to zero. The calculation module is used to obtain the jet aerodynamic interference factor based on the jet-free data, the jet-without data, and the nozzle thrust calibration data; and in the same wind tunnel test, using the same aerodynamic characteristic data, to calculate the difference between the measured values ​​of the jet-without data under the jet-without condition and the jet-without data under the jet-without condition, and obtain the change data caused by the jet.

7. The apparatus according to claim 6, characterized in that, The wind tunnel test was completed using an ejector-type transient wind tunnel.

8. The apparatus according to claim 6, characterized in that, The nozzle in the wind tunnel test model is connected to the wind tunnel test model in a fixed integrated manner.

9. The apparatus according to claim 6, characterized in that, In both the no-spray test and the sprayed test, the preset angle of attack or preset sideslip angle sequence is the same.

10. A storage medium for storing computer-executable instructions, characterized in that, When the computer-executable instructions are executed, they implement the steps of the wind tunnel jet interference force measurement test method according to any one of claims 1-5.

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