A high-response temperature sensor tube wind tunnel dynamic temperature calibration system and method

Abstract

The application discloses a pipe wind tunnel dynamic temperature calibration system and method of a high-response temperature sensor, and belongs to the technical field of temperature measurement testing and calibration. The application comprises a pipe wind tunnel body, an air source device, a cross harrow and a measuring device. The pipe wind tunnel body is internally connected with the air source device. The pipe wind tunnel body is provided with the measuring device at the tail end. The calibrated temperature sensor is installed on the measuring device. The cross harrow is arranged in the pipe wind tunnel body. The high-response step temperature required by the calibrated temperature sensor during dynamic calibration is generated through the air source device and the pipe wind tunnel body. The fixed installation of multiple calibrated temperature sensors and the sensing of high-temperature airflow are realized through the cross harrow. The measurement of various parameters required by dynamic calibration is realized through the measuring device. The application can provide a microsecond step temperature environment, accurately acquire the precision and time constant of the calibrated temperature sensor, and realize the dynamic calibration, in-situ calibration and batch calibration of the temperature sensor under the condition of high-temperature high-speed airflow.

Description

Technical Field

[0001] The invention relates to a dynamic temperature calibration system and method for a wind tunnel with a high-response temperature sensor, belonging to the technical field of temperature measurement, testing and calibration. Background Art

[0002] With the rapid development of the aerospace and defense sectors, dynamic temperature measurement is increasingly demanding in applications such as combustion diagnostics in aircraft engine combustors, ground testing of hypersonic ramjet engines, hypersonic boundary layer transition heat flow testing, and high-energy weapon damage effect assessment. Currently, many temperature sensors used in these applications require response speeds in the millisecond or even microsecond range. Ensuring the accuracy and reliability of these temperature sensor measurements is crucial for improving the quality of national dynamic temperature measurement and, ultimately, national defense science and technology. During dynamic temperature measurement, ambient temperature fluctuates rapidly over time. Due to the thermal inertia and limited heat conduction of the temperature-sensing components in the temperature sensor, a discrepancy between the temperature measured by the sensor and the temperature of the measured medium occurs, resulting in what is known as dynamic response error. To reduce this error and improve the reliability and validity of temperature sensor measurement data, dynamic calibration is often required. This involves studying the dynamic response characteristics of the temperature sensor using a traceable, rapidly varying temperature excitation signal and correcting the measurement results to more closely approximate the actual measured temperature.

[0003] Currently, the commonly used dynamic calibration methods for temperature sensors are water / oil bath, laser, and shock tube. All of these methods place the sensor being calibrated in a constructed stable high-temperature environment to produce a step temperature response. However, these methods have their own shortcomings. The water / oil bath method is only suitable for temperature sensors with slow response speeds. The resulting step high-temperature environment cannot meet the calibration requirements of millisecond or microsecond temperature sensors. In addition, most calibrated sensors are used in gas environments. Both this method and the laser calibration method suffer from the mismatch between the calibration medium and the operating medium, resulting in poor practicality of the calibration results. Due to the shortcomings of the above two methods, the shock tube calibration method is widely used. A shock tube is a device that is divided into two sections of pipes, a high-pressure section and a low-pressure section, by a diaphragm. When the pressure difference between the two sections of the pipe reaches the critical pressure of the diaphragm, that is, exceeds the pressure limit of the diaphragm, the diaphragm spontaneously ruptures, forming a shock wave and generating an instantaneous step signal. It can not only produce a microsecond step temperature environment, but also solve the problem of inconsistency between the calibration medium and the actual application medium. However, for dynamic temperature sensors used in relevant wind tunnel test measurements, in-situ dynamic calibration cannot be achieved using a shock tube method, and it is difficult to ensure the measurement accuracy of the sensor under actual working conditions; due to the limitations of the shock tube size and the installation and fixing method of the calibrated sensor, it is easy to cause installation step differences due to the mismatch of the installation dimensions between the connector, sensor, and end face, affecting the calibration results, and it is difficult to meet the batch calibration needs of dynamic temperature sensors.

[0004] Therefore, it is urgent to propose a dynamic temperature calibration system and method for a wind tunnel with a high-response temperature sensor to solve the above technical problems. Summary of the Invention

[0005] In response to the shortcomings of the current conventional method for dynamic calibration of temperature sensors based on shock tubes, the present invention proposes a high-response temperature sensor wind tunnel dynamic temperature calibration system and method. The system can provide a microsecond-level step temperature environment, thereby simulating the actual working state of the dynamic temperature sensor under high-temperature, high-speed airflow conditions, accurately obtaining the accuracy and time constant of the calibrated temperature sensor, and realizing dynamic calibration and batch calibration of temperature sensors applied to high-temperature, high-speed airflow conditions, as well as in-situ calibration and batch calibration of temperature sensors applied to wind tunnel dynamic tests. A brief overview of the present invention is given below to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to identify key or important parts of the present invention, nor is it intended to limit the scope of the present invention.

[0006] The technical solution of the present invention:

[0007] Solution 1: A dynamic temperature calibration system for a wind tunnel based on a high-response temperature sensor includes a wind tunnel body, an air source device, a cross rake, and a measuring device. The air source device is connected to the interior of the wind tunnel body, and a measuring device is provided at the end of the wind tunnel body. The temperature sensor to be calibrated is mounted on the measuring device, and a cross rake is arranged in the wind tunnel body. The high-response step temperature required for the calibrated temperature sensor during dynamic calibration is generated through the air source device and the wind tunnel body. The cross rake is used to achieve fixed installation of multiple calibrated temperature sensors and perception of high-temperature airflow, and the measuring device is used to measure various parameters required for dynamic calibration.

[0008] Preferably, the tube wind tunnel body includes a high-pressure driving section, a double-diaphragm section, a low-pressure driven section, a nozzle section and a test chamber; the high-pressure driving section, the double-diaphragm section, the low-pressure driven section, the nozzle section and the test chamber are sealed and connected in sequence; and the secondary diaphragm is arranged between the low-pressure driven section and the nozzle section.

[0009] Preferably, the gas source device includes a high-pressure gas tank, a pipeline and a valve. The high-pressure gas tank is connected to the interior of the wind tunnel body through the pipeline, and the valve is provided on the pipeline.

[0010] Preferably, the valve includes a pressure regulating valve, a high-pressure driving section air charging stop valve, a high-pressure driving section air discharging stop valve, a double-membrane section air charging stop valve, a double-membrane section air discharging stop valve, a low-pressure driven section air charging stop valve, and a low-pressure driven section air discharging stop valve, the pressure regulating valve is installed at the outlet of the high-pressure tank, the high-pressure driving section is connected with the high-pressure driving section air charging stop valve and the high-pressure driving section air discharging stop valve, the high-pressure driving section air charging stop valve is installed on the pipeline connected with the high-pressure tank, the double-membrane section is connected with the double-membrane section air charging stop valve and the double-membrane section air discharging stop valve, the double-membrane section air charging stop valve is installed on the pipeline connected with the high-pressure tank, the low-pressure driven section is connected with the low-pressure driven section air charging stop valve and the low-pressure driven section air discharging stop valve, and the low-pressure driven section air charging stop valve is installed on the pipeline connected with the high-pressure tank.

[0011] Preferably, the cross harrow includes a harrow body, a probe, and a lifting mechanism, the harrow body is installed on the lifting mechanism, the harrow body is arranged in the test cabin, and the probe is installed on the harrow body.

[0012] Preferably, the measuring device includes a dynamic acquisition device and a matching sensor, the dynamic acquisition device is connected with the lifting mechanism and the matching sensor respectively, and the matching sensor is arranged in the low-pressure driven section.

[0013] Preferably, the matching sensor includes a low-pressure driven section initial pressure sensor, a low-pressure driven section initial temperature sensor, an upstream speed sensor, and a downstream speed sensor, the low-pressure driven section initial pressure sensor, the low-pressure driven section initial temperature sensor, the upstream speed sensor, and the downstream speed sensor are sequentially installed in the low-pressure driven section, the low-pressure driven section initial pressure sensor is used to collect an output signal of an initial pressure, the low-pressure driven section initial temperature sensor is used to collect an output signal of a temperature, the upstream speed sensor is used to collect an upstream speed trigger signal, and the downstream speed sensor is used to collect a downstream speed trigger signal.

[0014] Scheme II, a pipe wind tunnel dynamic temperature calibration method of a high-response temperature sensor, is realized by relying on the pipe wind tunnel dynamic temperature calibration system of the high-response temperature sensor in scheme I, and includes the following steps.

[0015] Step 1: confirming basic parameters, confirming an operating environment temperature T of the calibrated temperature sensor and an air flow temperature ; confirming a range P of the low-pressure driven section initial pressure sensor, the initial state of the low-pressure driven section being normal pressure and normal temperature, collecting output signals of the low-pressure driven section initial pressure sensor and the low-pressure driven section initial temperature sensor, and determining a shock Mach number of the pipe wind tunnel and a high-pressure driving end pressure ;

[0016] Step 2: Install the calibrated temperature sensor on the cross rake. Put the cross rake into position by using the lifting mechanism to move the rake body to a position where its center coincides with the axis of the wind tunnel body.

[0017] Step 3: Install the diaphragm, inflate the high-pressure drive section and the double diaphragm section, that is, install the diaphragm and secondary diaphragm of the double diaphragm section, and pressurize the high-pressure drive section and the double diaphragm section at the same time. ;

[0018] Step 4: Deflate the double-diaphragm section. After the lifting mechanism moves the rake to a position where its center coincides with the axis of the wind tunnel body, open the double-diaphragm section deflation stop valve to quickly release the internal pressure of the double-diaphragm section. The diaphragm and secondary diaphragm in the double-diaphragm section rupture, and the calibration test begins.

[0019] Step 5: The upstream speed sensor and the downstream speed sensor give a trigger signal, start collecting the output signal of the calibrated temperature sensor, and record the trigger time interval between the upstream speed sensor and the downstream speed sensor giving the trigger signal;

[0020] Step 6: Calculate and analyze the dynamic indicators of the calibrated temperature sensor, analyze and calculate the uncertainty C and time constant of the calibrated temperature sensor .

[0021] The present invention has the following beneficial effects:

[0022] 1. The present invention provides a dynamic temperature calibration system for a wind tunnel with a high-response temperature sensor. While generating a step temperature environment with a response speed of milliseconds or even microseconds, the system solves the problem of inconsistency between the calibration medium and the actual application medium, and realizes the fixed installation of multiple calibrated temperature sensors and the perception of high-temperature airflow through a cross rake inside the wind tunnel test chamber. The cross rake facilitates its fixation and the perception of high-temperature airflow. Compared with traditional shock tube calibration, the installation method is more convenient and flexible, overcoming the calibration result error caused by the mismatch and unevenness between the connector and sensor size and the shock tube end face. Thanks to the multi-probe structure of the cross rake, dynamic calibration of multiple temperature sensors can be achieved in one calibration test, meeting batch calibration needs and improving calibration work efficiency.

[0023] 2. The present invention can be used not only as a calibration wind tunnel but also in related dynamic wind tunnel tests. The temperature sensor based on the dynamic test of the wind tunnel is in the same working conditions and system composition environment during calibration and actual use, thus achieving in-situ calibration. Compared with conventional shock tube laboratory calibration, it more truly reflects the measurement error of the sensor under actual working conditions, becoming an important means to ensure the normal operation of the sensor and improve monitoring accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1It is a stereogram of a dynamic temperature calibration system for a tube wind tunnel based on a high-response temperature sensor;

[0025] Figure 2 This is a flow chart for dynamic temperature calibration of a tube wind tunnel based on a high-response temperature sensor;

[0026] In the figure: 1-high-pressure driving section, 2-double-diaphragm section, 3-low-pressure driven section, 4-secondary diaphragm, 5-nozzle section, 6-test chamber, 7-high-pressure gas tank, 8-pipeline, 9-valve, 9-1-pressure regulating valve, 9-2-high-pressure driving section charging stop valve, 9-3-high-pressure driving section deflation stop valve, 9-4-double-diaphragm section charging stop valve, 9-5-double-diaphragm section deflation stop valve, 9-6-low-pressure driven section charging stop valve, 9-7-low-pressure driven section deflation stop valve, 10-rake body, 11-probe, 12-lifting mechanism, 13-dynamic acquisition equipment, 14-supporting sensors, 14-1-low-pressure driven section initial pressure sensor, 14-2-low-pressure driven section initial temperature sensor, 14-3-upstream speed sensor, 14-4-downstream speed sensor, 15-calibrated temperature sensor. DETAILED DESCRIPTION

[0027] To make the objectives, technical solutions, and advantages of the present invention more clearly apparent, the present invention is described below using specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely illustrative and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present invention.

[0028] Specific implementation method 1: Combination Figure 1 The present embodiment is described. A dynamic temperature calibration system for a wind tunnel based on a high-response temperature sensor in this embodiment includes a wind tunnel body, an air source device, a cross rake and a measuring device. The air source device is connected to the inside of the wind tunnel body, a measuring device is provided at the end of the wind tunnel body, the calibrated temperature sensor 15 is installed on the measuring device, and a cross rake is arranged in the wind tunnel body. The high-response step temperature required for the calibrated temperature sensor 15 during dynamic calibration is generated through the air source device and the wind tunnel body. The fixed installation of multiple calibrated temperature sensors 15 and the perception of high-temperature airflow are achieved through the cross rake, and the measurement of various parameters required for dynamic calibration is achieved through the measuring device.

[0029] The tube wind tunnel body comprises a high-pressure driving section 1, a double-diaphragm section 2, a low-pressure driven section 3, a nozzle section 5, and a test chamber 6. These sections are sealed and connected in sequence, with a secondary diaphragm 4 positioned between the low-pressure driven section 3 and the nozzle section 5. Multiple nozzle sections 5 with different Mach numbers can be configured to meet different simulation requirements, such as those with Mach numbers of 3, 3.5, 4, 4.5, 5, 6, 7, 8, or 10.

[0030] The gas source device includes a high-pressure gas tank 7, a pipeline 8 and a valve 9. The high-pressure gas tank 7 is connected to the interior of the wind tunnel body through the pipeline 8. The valve 9 is provided on the pipeline 8 to provide the driving gas required to generate the step pressure and the filling and discharging actions.

[0031] The valve 9 includes a pressure regulating valve 9-1, a high-pressure driving section inflation stop valve 9-2, a high-pressure driving section deflation stop valve 9-3, a double-membrane section inflation stop valve 9-4, a double-membrane section deflation stop valve 9-5, a low-pressure driven section inflation stop valve 9-6 and a low-pressure driven section deflation stop valve 9-7. The pressure regulating valve 9-1 is installed at the air outlet of the high-pressure gas tank 7, the high-pressure driving section 1 is connected to the high-pressure driving section inflation stop valve 9-2 and the high-pressure driving section deflation stop valve 9-3, the high-pressure driving The segment inflation stop valve 9-2 is installed on the pipeline 8 connected to the high-pressure gas tank 7, the double-membrane segment 2 is connected to the double-membrane segment inflation stop valve 9-4 and the double-membrane segment deflation stop valve 9-5, the double-membrane segment inflation stop valve 9-4 is installed on the pipeline 8 connected to the high-pressure gas tank 7, the low-pressure driven segment 3 is connected to the low-pressure driven segment inflation stop valve 9-6 and the low-pressure driven segment deflation stop valve 9-7, the low-pressure driven segment inflation stop valve 9-6 is installed on the pipeline 8 connected to the high-pressure gas tank 7.

[0032] The cross rake realizes the installation and fixation of the calibrated temperature sensor 15 in the direction of the upstream airflow. It includes a rake body 10, a probe 11 and a lifting mechanism 12. The rake body 10 is installed on the lifting mechanism 12. The rake body 10 is placed inside the test chamber 6, and the probe 11 is installed on the rake body 10. The calibrated temperature sensor 15 is installed on the probe 11. The rake body 10 is a cross structure, the number of probes 11 is 17, and the calibrated temperature sensor 15 is installed at the end of the probe 11.

[0033] The measuring device includes a dynamic acquisition device 13 and a matching sensor 14. The dynamic acquisition device 13 is connected to the lifting mechanism 12 and the matching sensor 14 respectively. The matching sensor 14 is arranged in the low-voltage driven section 3 to realize the acquisition of initial pressure, temperature, speed measurement trigger signal and output signal of the measured sensor.

[0034] The supporting sensors 14 include a low-pressure driven section initial pressure sensor 14-1, a low-pressure driven section initial temperature sensor 14-2, an upstream speed sensor 14-3 and a downstream speed sensor 14-4. The low-pressure driven section initial pressure sensor 14-1, the low-pressure driven section initial temperature sensor 14-2, the upstream speed sensor 14-3 and the downstream speed sensor 14-4 are installed in sequence in the low-pressure driven section 3. The low-pressure driven section initial pressure sensor 14-1 is used to collect the output signal of the initial pressure, the low-pressure driven section initial temperature sensor 14-2 is used to collect the output signal of the temperature, the upstream speed sensor 14-3 is used to collect the upstream speed trigger signal, and the downstream speed sensor 14-4 is used to collect the downstream speed trigger signal.

[0035] Specific implementation method 2: Combination Figure 1-Figure 2 This embodiment describes a dynamic temperature calibration system for a wind tunnel using a high-response temperature sensor. This embodiment is based on the dynamic temperature calibration system for a wind tunnel using a high-response temperature sensor described in Specific Embodiment 1 and includes the following steps:

[0036] Step 1: Confirm the basic parameters, confirm the working environment temperature T and air flow temperature of the calibrated temperature sensor 15 Confirm the range P of the low-pressure driven section initial pressure sensor 14-1, the initial state of the low-pressure driven section 3 is normal pressure and temperature, collect the output signals of the low-pressure driven section initial pressure sensor 14-1 and the low-pressure driven section initial temperature sensor 14-2, and determine the shock wave Mach number of the tube wind tunnel and high pressure drive end pressure ;

[0037] Shock wave Mach number in a wind tunnel The method for determining is as follows:

[0038]

[0039]

[0040] Where, is the shock front temperature; is the initial temperature of the low-voltage driven section, directly measured by the temperature sensor; is the specific heat ratio, take 1.4.

[0041] High pressure driving pressure The determination method is as follows:

[0042]

[0043] Where, for Initial pressure of the low-pressure driven section;

[0044] Step 2: Install the calibrated temperature sensor 15 on the cross rake, and the cross rake is in place, i.e. the rake body 10 is moved to the position where the center thereof coincides with the axis of the pipe wind tunnel body by the lifting mechanism 12;

[0045] Step 3: Install the diaphragm, inflate the high-pressure driving section 1 and the double-membrane section 2, i.e. install the diaphragm and the secondary diaphragm 4 of the double-membrane section 2, and simultaneously pressurize the high-pressure driving section 1 and the double-membrane section 2 to ;

[0046] Step 4: Deflate the double-membrane section 2, after the lifting mechanism 12 moves the rake body 10 to the position where the center thereof coincides with the axis of the pipe wind tunnel body, open the double-membrane section deflation stop valve 9-5, quickly release the pressure inside the double-membrane section 2, the diaphragm and the secondary diaphragm 4 inside the double-membrane section 2 are broken, and the calibration test starts;

[0047] Step 5: The upstream speed sensor 14-3 and the downstream speed sensor 14-4 give a trigger signal, start collecting the output signal of the calibrated temperature sensor 15, and record the trigger time interval when the upstream speed sensor 14-3 and the downstream speed sensor 14-4 give the trigger signal;

[0048] Step 6: Calculate and analyze the dynamic indicators of the calibrated temperature sensor 15, analyze and calculate the uncertainty C of the calibrated temperature sensor 15 and the time constant , and set the confidence interval to determine the expanded uncertainty to ensure the preparedness and reliability of the calibration results.

[0049] The method for obtaining the measurement accuracy of the calibrated temperature sensor 15 is to obtain the uncertainty by calculating the ratio of the collection average value collected after the calibrated temperature sensor 15 realizes step stabilization to the actual air flow temperature .

[0050]

[0051] The method for obtaining the time constant is as follows: when the system receives a unit step signal excitation, the response signal thereof is shown in the following formula, and the time required for the step response curve to reach 1-1 / e (i.e. 63.2%) of the steady-state value is generally defined as the time constant of the system .

[0052]

[0053] In the formula, is the system output signal, is the system input signal.

[0054] Specific implementation method three: in combination with Figure 1-Figure 2This embodiment is described based on the second embodiment. A dynamic temperature calibration method for a wind tunnel using a high-response temperature sensor is described as follows:

[0055] Step 1: Confirm the basic parameters, confirm that the working environment temperature T of the calibrated temperature sensor 15 is 0-1200K, the air flow temperature The initial pressure sensor 14-1 of the low-pressure driven section is 320°C. The range P of the low-pressure driven section initial pressure sensor 14-1 is confirmed to be 120 kPa. The initial state of the low-pressure driven section 3 is normal pressure and temperature. The output signal of the low-pressure driven section initial pressure sensor 14-1 is 101.54 kPa. The output signal of the low-pressure driven section initial temperature sensor 14-2 is 28.26°C. The shock wave Mach number of the duct wind tunnel is determined. and high pressure drive end pressure ;

[0056] The method for determining the shock wave Mach number M of a tube wind tunnel is as follows:

[0057]

[0058]

[0059] Where, is the shock front temperature; is the initial temperature of the low-voltage driven section, directly measured by the temperature sensor; is the specific heat ratio, which is taken as 1.4. The shock wave Mach number M of the tube wind tunnel is calculated to be 3.05.

[0060] High pressure driving pressure The determination method is as follows:

[0061]

[0062] Calculate the high pressure drive pressure It is 496.4kPa.

[0063] Step 2: Install 17 calibrated temperature sensors 15 on the cross rake. The cross rake is in place, that is, the rake body 10 is moved by the lifting mechanism 12 to a position where its center coincides with the axis of the wind tunnel body.

[0064] Step 3: Install the diaphragm and inflate the high-pressure drive section 1 and the double diaphragm section 2. Install the diaphragm of the double diaphragm section 2 and the secondary diaphragm 4, set the pressure regulating valve 9-1, open the high-pressure drive section inflation stop valve 9-2 and the double diaphragm section inflation stop valve 9-4, and pressurize the high-pressure drive section 1 and the double diaphragm section 2 simultaneously. , then closed;

[0065] Step 4: Deflate the double-membrane segment 2. After the lifting mechanism 12 moves the rake body 10 to a position where its center coincides with the axis of the wind tunnel body, open the double-membrane segment deflation stop valve 9-5 to quickly release the internal pressure of the double-membrane segment 2. The diaphragm and secondary diaphragm 4 in the double-membrane segment 2 rupture, and the calibration test begins.

[0066] Step 5: The upstream speed sensor 14 - 3 and the downstream speed sensor 14 - 4 generate trigger signals, start collecting the output signal of the calibrated temperature sensor 15 , and record the trigger time interval between the upstream speed sensor 14 - 3 and the downstream speed sensor 14 - 4 generating the trigger signals;

[0067] Step 6: Calculate and analyze the dynamic indicators of the calibrated temperature sensor 15, and analyze and calculate the uncertainty C and time constant of the calibrated temperature sensor 15 ,At the same time, in order to ensure the readiness and reliability of the calibration results, a confidence interval is set to determine the expanded uncertainty.

[0068] The method for obtaining the measurement accuracy of the calibrated temperature sensor 15 is as follows: the average value of the collected data after the calibrated temperature sensor 15 achieves step stabilization is calculated. The actual air flow temperature The uncertainty is obtained by the ratio relationship of .

[0069]

[0070] Time constant The method of obtaining is: when the system receives a unit step signal excitation, its response signal is shown in the following formula. Generally, the time required for the step response curve to reach 1-1 / e (i.e. 63.2%) of the steady-state value is defined as the time constant of the system. .

[0071]

[0072] According to the time domain response curve, the time constant is finally obtained The accuracy is 0.1%, the expanded uncertainty is 0.2%, and the confidence interval k is 2.

[0073] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be permuted and combined. Those skilled in the art can exhaust all possibilities based on the mathematical knowledge of permutations and combinations. Therefore, the present invention will no longer describe the technical solutions after permutations and combinations one by one, but it should be understood that the technical solutions after permutations and combinations have been disclosed by the present invention.

[0074] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A dynamic temperature calibration system for a wind tunnel with a high-response temperature sensor, characterized by: The invention comprises a pipe wind tunnel body, an air source device, a cross rake and a measuring device. The pipe wind tunnel body is connected to the air source device, the measuring device is arranged at the end of the pipe wind tunnel body, the calibrated temperature sensor (15) is installed on the measuring device, and the cross rake is arranged in the pipe wind tunnel body. The high response step temperature required by the calibrated temperature sensor (15) during dynamic calibration is generated by the air source device and the pipe wind tunnel body. The fixed installation of multiple calibrated temperature sensors (15) and the perception of high-temperature airflow are achieved by the cross rake. The measurement of various parameters required for dynamic calibration is achieved by the measuring device. The tube wind tunnel body comprises a high-pressure driving section (1), a double-membrane section (2), a low-pressure driven section (3), a nozzle section (5) and a test chamber (6); the high-pressure driving section (1), the double-membrane section (2), the low-pressure driven section (3), the nozzle section (5) and the test chamber (6) are sealed and connected in sequence; and the secondary diaphragm (4) is arranged between the low-pressure driven section (3) and the nozzle section (5); The gas source device comprises a high-pressure gas tank (7), a pipeline (8) and a valve (9); the high-pressure gas tank (7) is connected to the interior of the wind tunnel body via the pipeline (8); and the pipeline (8) is provided with a valve (9); The cross rake comprises a rake body (10), a probe (11) and a lifting mechanism (12), wherein the rake body (10) is mounted on the lifting mechanism (12), the rake body (10) is placed inside the test chamber (6), and the probe (11) is mounted on the rake body (10), and the calibrated temperature sensor (15) is mounted on the probe (11); The measuring device comprises a dynamic acquisition device (13) and a matching sensor (14), wherein the dynamic acquisition device (13) is connected to the lifting mechanism (12) and the matching sensor (14) respectively, and the matching sensor (14) is arranged in the low-voltage driven section (3); The supporting sensor (14) comprises a low-pressure driven section initial pressure sensor (14-1), a low-pressure driven section initial temperature sensor (14-2), an upstream speed sensor (14-3) and a downstream speed sensor (14-4); the low-pressure driven section initial pressure sensor (14-1), the low-pressure driven section initial temperature sensor (14-2), the upstream speed sensor (14-3) and the downstream speed sensor (14-4) are sequentially installed in the low-pressure driven section (3); A method for dynamic temperature calibration of a wind tunnel using a high-response temperature sensor is implemented based on the above-mentioned dynamic temperature calibration system for a wind tunnel using a high-response temperature sensor, and includes the following steps: Step 1: Confirm the basic parameters, confirm the working environment temperature T and air flow temperature T of the calibrated temperature sensor (15) 02 ; Confirm the range P of the low-pressure driven section initial pressure sensor (14-1), the initial state of the low-pressure driven section (3) is normal pressure and normal temperature, collect the output signals of the low-pressure driven section initial pressure sensor (14-1) and the low-pressure driven section initial temperature sensor (14-2), and determine the shock wave Mach number M of the tube wind tunnel and the high-pressure driving end pressure P4; The method for determining the shock wave Mach number M of a tube wind tunnel is as follows: T5=T 02 Where, T5 is the shock front temperature; T1 is the initial temperature of the low-pressure driven section, which is directly measured by the temperature sensor; γ is the specific heat ratio, which is taken as 1.4; The method for determining the high-pressure driving pressure P4 is as follows: Where, P1 is the initial pressure of the low-pressure driven section; Step 2: The calibrated temperature sensor (15) is mounted on the cross rake, and the cross rake is in place, that is, the rake body (10) is moved to a position where its center coincides with the axis of the wind tunnel body through the lifting mechanism (12); Step 3: Install the diaphragm and inflate the high-pressure drive section (1) and the double-diaphragm section (2), i.e. install the diaphragm of the double-diaphragm section (2) and the secondary diaphragm (4), and simultaneously pressurize the high-pressure drive section (1) and the double-diaphragm section (2) to P4; Step 4: Deflate the double membrane segment (2). After the lifting mechanism (12) moves the rake body (10) to a position where its center coincides with the axis of the wind tunnel body, open the double membrane segment deflation stop valve (9-5) to quickly release the internal pressure of the double membrane segment (2). The diaphragm and secondary diaphragm (4) in the double membrane segment (2) rupture, and the calibration test begins. Step 5: The upstream speed sensor (14-3) and the downstream speed sensor (14-4) give a trigger signal, start collecting the output signal of the calibrated temperature sensor (15), and record the trigger time interval of the upstream speed sensor (14-3) and the downstream speed sensor (14-4) giving the trigger signal; Step 6: Calculate and analyze the dynamic index of the calibrated temperature sensor (15), and analyze and calculate the uncertainty C and the time constant τ of the calibrated temperature sensor (15); The method for obtaining the measurement accuracy of the calibrated temperature sensor 15 is as follows: by calculating the average value ΔT collected after the calibrated temperature sensor 15 achieves step stabilization and the actual airflow temperature T 02 The uncertainty is obtained by the ratio relationship of The method for obtaining the time constant τ is as follows: when the system is excited by a unit step signal, its response signal is shown in the following formula. Generally, the time required for the step response curve to reach 1-1 / e (i.e. 63.2%) of the steady-state value is defined as the time constant τ of the system; s(t)=[1-e -t / τ ]u(t) Where s(t) is the system output signal and u(t) is the system input signal.

2. The high-response temperature sensor dynamic temperature calibration system for a wind tunnel according to claim 1, characterized in that: The valve (9) comprises a pressure regulating valve (9-1), a high-pressure driving section inflation stop valve (9-2), a high-pressure driving section deflation stop valve (9-3), a double-membrane section inflation stop valve (9-4), a double-membrane section deflation stop valve (9-5), a low-pressure driven section inflation stop valve (9-6) and a low-pressure driven section deflation stop valve (9-7); a pressure regulating valve (9-1) is installed at the gas outlet of the high-pressure gas tank (7); the high-pressure driving section (1) is connected to the high-pressure driving section inflation stop valve (9-2) and the high-pressure driving section deflation stop valve (9-3); the high-pressure driving section inflation stop valve (9-4) and the high-pressure driving section deflation stop valve (9-5) are connected to the high-pressure driving section inflation stop valve (9-6) and the high-pressure driving section deflation stop valve (9-7); The air stop valve (9-2) is installed on a pipeline (8) connected to a high-pressure gas tank (7); the double-membrane segment (2) is connected to a double-membrane segment air-inflating stop valve (9-4) and a double-membrane segment air-deflating stop valve (9-5); the double-membrane segment air-inflating stop valve (9-4) is installed on a pipeline (8) connected to a high-pressure gas tank (7); the low-pressure driven segment (3) is connected to a low-pressure driven segment air-inflating stop valve (9-6) and a low-pressure driven segment air-deflating stop valve (9-7); the low-pressure driven segment air-inflating stop valve (9-6) is installed on a pipeline (8) connected to a high-pressure gas tank (7).

Images