Total temperature and total pressure synchronous measurement method and system based on fluorescent optical fiber

Abstract

The invention relates to a total temperature and total pressure synchronous measurement method and system based on a fluorescent optical fiber, and the method comprises the steps: generating an excitation light signal, inputting the excitation light signal into a synthesis end fiber core disposed on a to-be-measured airflow path, and enabling the outer side of the synthesis end fiber core to comprise a temperature-sensitive coating and a pressure-sensitive coating; acquiring a mixed optical signal generated when the to-be-detected airflow passes through the temperature-sensitive coating and the pressure-sensitive coating; and filtering the mixed optical signal to obtain a temperature optical signal and a pressure optical signal, and calculating a light intensity ratio to obtain total temperature information and total pressure information of the flow field. Compared with the prior art, integrated measurement of the total temperature and the total pressure is achieved, and the method has the advantages of being insensitive in incoming flow angle, high in measurement accuracy, wide in application scene and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of flow field testing, and in particular to a total temperature and total pressure synchronous measurement method and system based on fluorescent optical fiber. Background Art

[0002] Accurately measuring the pressure and temperature fields of airflow is crucial for the development of high-performance aircraft engines. Compressors and turbines are crucial components of aircraft engines, and their efficiency directly determines their performance. To determine the efficiency of compressors and turbines, it is necessary to measure the total temperature and total pressure parameters at their inlets and outlets, particularly the simultaneous measurement of total temperature and total pressure. With the continuous development of aircraft engines, the environments within compressors and turbines are becoming increasingly complex and diverse. Detailed measurement of the flow fields within compressors and turbines places higher demands on the measurement of total temperature and total pressure.

[0003] Currently, thermocouple sensors are commonly used to measure total flow temperature. However, thermocouples are susceptible to the measurement environment, especially in harsh environments such as high temperature and high humidity. They can suffer from large measurement errors, are susceptible to electromagnetic interference, and have a small insensitivity angle to the incoming flow direction. Furthermore, the thin diameter of the thermocouple wire makes it prone to breakage, especially in high-speed flow fields. Multi-hole probes are commonly used to measure total flow pressure, but due to their limited measurement principle, the probes are large in size.

[0004] At the same time, to simultaneously obtain total temperature and total pressure data for a specific area of ​​the flow field, a combined probe that combines both measurement methods is often used. This dramatically increases the probe's size, significantly reduces the spatial resolution of the measurement, increases the probe's interference with the flow field, and limits the probe's ability to measure in confined spaces. Furthermore, the remote location of the sensor can lead to significant errors between the measured results and the actual values.

[0005] Chinese patent application publication number CN115753130A provides an enthalpy probe for obtaining the enthalpy value of a high-enthalpy flow field based on an optical method. A pressure measuring module connected to an external pressure sensor is provided on the central axis of the probe, and a temperature measuring module for measuring the total temperature of the flow field is provided on one side of the pressure measuring module. That is, a single-hole total pressure probe and an optical fiber total temperature probe are integrated into one probe to achieve synchronous measurement of total temperature and total pressure. However, this integration method cannot always avoid the shortcomings of the combined probe. The probe size is too large to ensure that the synchronously measured total temperature and total pressure parameters come from the requirement of close streamlines as much as possible, and the probe has a large interference on the test flow field. At the same time, the design of the single-hole pressure measurement makes the total pressure measurement highly sensitive to the incoming flow direction and has a large error, and can only achieve steady-state pressure measurement.

[0006] The engine intake total temperature and total pressure probe and engine intake total temperature and total pressure measurement system provided by Chinese patent application publication number CN115753130A integrates a fiber optic pressure sensor with a pressure-sensitive unit and a fiber optic temperature sensor with a temperature-sensitive unit side by side in a stagnation cover to achieve synchronous measurement of total temperature and total pressure. Although this probe is completely based on fiber optic sensors, the two optical fibers need to adopt a side-by-side staggered design, that is, the pressure measuring fiber is in front and the temperature measuring fiber is in the back, which also reduces the spatial resolution of the measurement, and the pressure measuring fiber is susceptible to flow disturbances caused by the temperature measuring fiber, which increases the total pressure measurement error. At the same time, the air inlet of the stagnation cover is opposite to the end face of the optical fiber, that is, the air inlet direction is parallel to the optical fiber axis, so that the probe needs to adopt an L-shaped design when performing actual measurements, which causes the optical fiber to bend and cannot penetrate into narrow areas for flow field measurement.

[0007] In summary, in order to solve the difficult problem of refined synchronous measurement of total temperature and total pressure in complex flow fields, it is urgently necessary to develop a method and system with stable operation, a large range of insensitive angles for incoming flow, high spatial resolution, little interference to the flow field, and the ability to achieve synchronous measurement of total temperature and total pressure in the same area. Summary of the Invention

[0008] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a total temperature and total pressure synchronous measurement method and system based on fluorescent optical fiber, so as to solve or partially solve the problem of low probe integration caused by separate measurement of total temperature and total pressure.

[0009] The purpose of the present invention can be achieved by the following technical solutions:

[0010] One aspect of the present invention provides a method for synchronously measuring total temperature and total pressure based on fluorescent optical fiber, comprising the following steps:

[0011] Step S1, generating an excitation light signal and inputting the signal into a synthetic end fiber core provided on the airflow path to be measured, wherein the outer side of the synthetic end fiber core includes a temperature-sensitive coating and a pressure-sensitive coating;

[0012] Step S2, obtaining a mixed light signal generated by the airflow to be measured passing through the temperature-sensitive coating and the pressure-sensitive coating;

[0013] Step S3: filtering the mixed optical signal to obtain a temperature optical signal and a pressure optical signal, and calculating the light intensity ratio to obtain total temperature information and total pressure information of the flow field.

[0014] Another aspect of the present invention provides a total temperature and total pressure synchronous measurement system based on fluorescent optical fiber, which is used to implement the aforementioned total temperature and total pressure synchronous measurement method based on fluorescent optical fiber. The total temperature and total pressure synchronous measurement system includes:

[0015] The probe head has an axial channel inside and an air inlet and an air outlet.

[0016] A synthetic end fiber core is fixed in the channel, and the outer side of the synthetic end fiber core includes a temperature-sensitive coating and a pressure-sensitive coating;

[0017] A signal transmitting unit, configured to generate an excitation light signal and input the signal into the synthesis end fiber core;

[0018] A pressure signal receiving unit is used to collect a mixed optical signal generated by the airflow to be measured passing through the temperature-sensitive coating and the pressure-sensitive coating, and filter it to obtain an optical signal that matches the wavelength of the pressure-sensitive coating;

[0019] A temperature signal receiving unit is used to collect a mixed optical signal generated by the airflow to be measured passing through the temperature-sensitive coating and the pressure-sensitive coating, and filter it to obtain an optical signal that matches the wavelength of the temperature-sensitive coating;

[0020] The pressure signal processing unit and the temperature signal processing unit are used to synchronously process the optical signal matching the wavelength of the pressure-sensitive coating and the optical signal matching the wavelength of the temperature-sensitive coating, respectively, to obtain the total temperature information and total pressure information of the flow field.

[0021] As a preferred technical solution, the temperature-sensitive coating and the pressure-sensitive coating are arranged at intervals, and the pressure-sensitive coating is facing the air inlet.

[0022] As an optimal technical solution, it includes multiple air inlet holes, which are facing the main flow measurement and are cross-shaped with the center line of the center hole as the axis of symmetry. The center line of the center hole is 0.8mm-5mm away from the top of the probe head 1. The center lines of the holes arranged circumferentially are perpendicular to the axis of the cylinder and intersect at the center of the circumferential cylindrical surface. The angle between adjacent circumferential holes is 15°-60°. The center lines of the holes arranged axially intersect at the leeward measuring point of the circumferential cylindrical surface where the center line of the center hole is located. The angle between adjacent axial holes is 5°-30°.

[0023] As a preferred technical solution, it includes multiple air outlet holes, which are arranged along the circumferential direction, with the center lines of the air outlet holes parallel and perpendicular to the cylindrical axis, and the distance between the center lines of the air outlet holes and the top of the probe head is 6mm-16mm.

[0024] As a preferred technical solution, the pressure-sensitive coating is a porous ceramic pressure-sensitive coating or a mesoporous ceramic pressure-sensitive coating, and the temperature-sensitive coating is MFG, Y2O3:Eu, YSZ:Eu, YVO4:Dy or YAG:Dy.

[0025] As a preferred technical solution, the signal transmitting unit includes a signal generator and a light source.

[0026] As a preferred technical solution, the pressure signal receiving unit includes a pressure signal bandpass optical filter and a pressure signal light detector connected in sequence, and the temperature signal receiving unit includes a temperature signal bandpass optical filter and a temperature signal light detector connected in sequence.

[0027] As a preferred technical solution, the total temperature and total pressure synchronous measurement system further includes:

[0028] The optical fiber coupler is connected to the signal transmitting unit through the optical fiber input end, connected to the pressure signal receiving unit and the temperature signal receiving unit through the optical fiber first output end and the optical fiber second output end respectively, and connected to the optical fiber core of the synthesis end through the optical fiber synthesis end.

[0029] As a preferred technical solution, the total temperature and total pressure synchronous measurement system further includes:

[0030] The synthetic end shell wraps one end of the synthetic end fiber core, and the synthetic end shell abuts against the probe head through insulating glue.

[0031] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0032] (1) Realizing the integrated measurement of total temperature and total pressure: The present invention sets up a synthetic end fiber core including a temperature-sensitive coating and a pressure-sensitive coating, and collects the mixed optical signal generated by the airflow to be measured passing through the temperature-sensitive coating and the pressure-sensitive coating, filters to obtain the temperature optical signal and the pressure optical signal, and obtains the total temperature information and the total pressure information of the flow field by calculating the light intensity ratio, thereby realizing the integrated measurement of the total temperature and total pressure. Through this design, a single optical fiber can be used to realize the synchronous measurement of the total temperature and total pressure at the same position in the flow field, while effectively shortening the distance between the pressure measuring point and the temperature measuring point, providing an efficient and accurate means for flow field testing.

[0033] (2) Insensitivity to incoming flow angle: The present invention adopts a cross-shaped multi-air inlet design, so that the probe measurement result has a large insensitive angle range to the incoming flow and is almost unaffected by the incoming flow direction.

[0034] (3) High measurement accuracy: The present invention makes full use of the flow characteristics of the air flow after passing through the air inlet. The pressure stagnation effect is best at the point opposite the air inlet, and the temperature stagnation heat exchange effect is best at the lower end of the air inlet. The layout of spraying pressure-sensitive material at the point opposite the air inlet and spraying temperature-sensitive material at the lower end of the air inlet makes the measurement results more accurate and the measurement accuracy is high.

[0035] (4) Wide range of application scenarios: The probe head of the present invention has a simple structure and a small size, which significantly improves the spatial resolution of the measurement and can realize the measurement of various narrow spaces. It also has little interference with the flow field. The probe is based on fluorescent fiber measurement and is not affected by electromagnetic interference, measurement environment humidity, etc. It is applicable to a wide range of measurement environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Flowchart of the total temperature and total pressure synchronous measurement method based on fluorescent optical fiber in an embodiment;

[0037] Figure 2 Schematic diagram of a total temperature and total pressure synchronous measurement system based on fluorescent optical fiber in an embodiment;

[0038] Figure 3 Schematic diagram of a total temperature and total pressure synchronous measurement probe based on fluorescent optical fiber in an embodiment;

[0039] Figure 4 for Figure 3 A partial schematic diagram of the fiber core at the middle synthesis end;

[0040] Figure 5 for Figure 3 Left view of;

[0041] Figure 6 for Figure 3 Right view of;

[0042] Figure 7 for Figure 3 A-direction view;

[0043] Figure 8 for Figure 3 B-direction view;

[0044] Figure 9 for Figure 6 C-direction view;

[0045] Figure 10 is a schematic diagram of an electronic device in an embodiment;

[0046] Among them, 01- total temperature and total pressure synchronous measurement probe based on fluorescent optical fiber, 02- signal transmitting unit, 021- signal generator, 022- light source, 03- pressure signal receiving unit, 031- pressure signal bandpass optical filter, 032- pressure signal light detector, 04- temperature signal receiving unit, 041- temperature signal bandpass optical filter, 042- temperature signal light detector, 05- pressure signal processing unit, 06- temperature signal processing unit, 1- probe head, 2- probe support rod, 3- air inlet, 4- air outlet, 5- channel, 6- synthetic end fiber core, 7- pressure sensitive coating, 8- temperature sensitive coating, 9- synthetic end shell, 10- insulating glue, 11- optical fiber synthetic end, 12- optical fiber input end, 13- optical fiber first output end, 14- optical fiber second output end, 15- optical fiber coupler. DETAILED DESCRIPTION

[0047] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0048] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is typically placed when in use. These terms are intended solely to facilitate the description of the present invention and simplify the description, and are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather that it may be slightly tilted.

[0049] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0050] Example 1

[0051] The existing technology has the following problems:

[0052] (1) The existing single-type probe cannot achieve simultaneous measurement of total temperature and total pressure in the same area of ​​the flow field.

[0053] (2) The existing combined probes are large in size, have great interference with the flow field, have low spatial resolution, and are difficult to measure in small areas.

[0054] (3) The measurement results of existing temperature probes and combined probes are affected by the direction of the incoming flow, and the insensitive angle to the incoming flow is small.

[0055] (4) Commonly used temperature probes are susceptible to electromagnetic interference and have large measurement errors in harsh environments such as high temperature and high humidity.

[0056] To address the above problems, this embodiment provides a method for synchronously measuring total temperature and total pressure based on fluorescent optical fiber. Figure 1 , the method comprises the following steps:

[0057] Step S1, generating an excitation light signal and inputting it into a synthetic end fiber core provided on the airflow path to be measured, wherein the outer side of the synthetic end fiber core includes a temperature-sensitive coating and a pressure-sensitive coating;

[0058] Step S2, obtaining a mixed light signal generated by the airflow to be measured passing through the temperature-sensitive coating and the pressure-sensitive coating;

[0059] In step S3, the mixed optical signal is filtered to obtain a temperature optical signal and a pressure optical signal, and the total temperature information and the total pressure information of the flow field are obtained by calculating the light intensity ratio.

[0060] To implement the above method, see Figure 2 This embodiment also provides a total temperature and total pressure synchronous measurement system based on fluorescent optical fiber, including a total temperature and total pressure synchronous measurement probe 01 based on fluorescent optical fiber, a signal transmitting unit (02), a pressure signal receiving unit 03, a temperature signal receiving unit 04, a pressure signal processing unit 05 and a temperature signal processing unit 06. Each part will be described separately below.

[0061] See also Figure 3 This is a schematic diagram of a total temperature and total pressure synchronous measurement probe 01 based on fluorescent optical fiber. The probe includes a probe head 1, a probe support rod 2, an air inlet 3, an air outlet 4, a channel 5, a synthetic end fiber core 6, a pressure-sensitive coating 7, a temperature-sensitive coating 8, a synthetic end shell 9, an insulating glue 10, an optical fiber synthetic end 11, an optical fiber input end 12, an optical fiber first output end 13, an optical fiber second output end 14 and an optical fiber coupler 15.

[0062] The probe head 1 is composed of a cylinder and a fast convergence curve rotating body. The probe head 1 has an air inlet 3 on the side facing the main flow and an air outlet 4 on the side facing away from the main flow. The probe head 1 has a channel 5 inside along the axial direction, and the channel 5 runs through the entire probe. Figure 8 , the channel 5 is equipped with an optical fiber synthesis end 11, see Figure 4 This is a partial schematic diagram of the synthetic end fiber core. The synthetic end fiber core 6 at the top of the optical fiber synthetic end 11 is sprayed with pressure-sensitive coating 7 and temperature-sensitive coating 8 from top to bottom. The optical fiber synthetic end 11 extends out of the tail of the probe support rod 2 and is coupled together with the optical fiber input end 12, the optical fiber first output end 13, and the optical fiber second output end 14 through the optical fiber coupler 15.

[0063] The diameter d of the cylinder of the probe head 1 is in the range of 1mm≤d≤6mm, and the length is 10mm-45mm. The curved rotating body can be formed by rotating an arc line, a double twist line or a conic section. The diameter of the circular channel 5 in the probe head 1 is 0.5mm-5mm, and 3mm is selected in this embodiment.

[0064] See also Figure 5The probe head 1 cylinder has an air inlet 3 on the side facing the main flow. The diameter of the air inlet 3 is 0.3mm-3mm. In this embodiment, 1.0mm is selected. The number of the air inlet 3 is 5 to 10. In this embodiment, 5 are selected. The center line of the center hole is used as the axis of symmetry and is in a cross shape. The distance between the center line of the center hole and the top of the probe head 1 is 0.8mm-5mm. In this embodiment, 3.8mm is selected. Figure 7 The center lines of the holes arranged along the circumferential direction are perpendicular to the axis of the cylinder and intersect at the center of the circumferential cylindrical surface. The angle between adjacent circumferential holes is 15° to 60°. In this embodiment, 35° is selected. The center lines of the holes arranged along the axial direction intersect at the leeward measuring point of the circumferential cylindrical surface where the center line of the center hole is located. The angle between adjacent axial holes is 5° to 30°. In this embodiment, 15° is selected.

[0065] See also Figure 6 The probe head 1 cylinder has an air outlet 4 on the side facing away from the main flow. The diameter of the air outlet 4 is 0.2mm-2mm. In this embodiment, 0.6mm is selected. The number of the air outlet 4 is 1 to 3. In this embodiment, 2 are selected. They are in a straight line along the circumference. Figure 9 The center lines of the air outlet holes 4 are parallel and perpendicular to the axis of the cylinder. The distance between the center lines of the air outlet holes 4 and the top of the probe head 1 is 6mm-16mm, and 10mm is selected in this embodiment.

[0066] The probe support rod 2 is a cylinder with a diameter D of 2 mm ≤ D ≤ 8 mm.

[0067] The diameter of the optical fiber synthesis end 11 is 0.5mm-3mm, and 1mm is selected in this embodiment. The optical fiber synthesis end 11 is composed of a synthesis end core 6 and a synthesis end shell 9. The diameter of the synthesis end core 6 is 0.2mm-2mm, and 0.5mm is selected in this embodiment. The length of the exposed synthesis end core 6 at the top of the optical fiber synthesis end 11 is 2mm-8mm, and 6mm is selected in this embodiment. The insulating glue 10 is used to fix the optical fiber synthesis end 11 to the probe head 1. The tail of the optical fiber synthesis end 11 is coupled with the optical fiber input end 12, the first optical fiber output end 13, and the second optical fiber output end 14 through the optical fiber coupler 15. The diameters of the optical fiber input end 12, the first optical fiber output end 13, and the second optical fiber output end 14 are all 0.2mm-2.5mm, and 0.4mm is selected in this embodiment.

[0068] The pressure-sensitive coating 7 is sprayed on the upper part of the exposed synthetic end fiber core 6 at a position opposite to the air inlet 3. After being excited by the input light, it emits excitation light carrying pressure information. The pressure-sensitive coating 7 can be a porous ceramic pressure-sensitive coating PC-PSP or a mesoporous ceramic pressure-sensitive coating MP-PSP. The spraying length is 0.5mm-4mm, and 2.9mm is selected in this embodiment. The spraying thickness is 0.003mm-0.01mm, and 0.005mm is selected in this embodiment.

[0069] The temperature-sensitive coating 8 is sprayed on the lower part of the exposed synthetic end fiber core 6, and emits excitation light carrying temperature information after being excited by the input light. The temperature-sensitive coating 8 is selected from transition metal-doped oxides, rare earth element-doped oxides or other suitable temperature-sensitive materials, and MFG, Y2O3:Eu, YSZ:Eu, YVO4:Dy or YAG:Dy can be selected. The spraying length is 0.5mm-4mm, and 12.8mm is selected in this embodiment; the spraying thickness is 0.001mm-0.01mm, and 0.005mm is selected in this embodiment.

[0070] It is important to note that the pressure-sensitive and temperature-sensitive coatings used must have different excitation light wavelengths to distinguish between pressure and temperature optical signals. The pressure signal receiving unit uses a pressure bandpass optical filter to filter out background light and non-pressure optical signals, ultimately obtaining total pressure data. The temperature signal receiving unit uses a temperature bandpass optical filter to filter out background light and non-temperature optical signals, ultimately obtaining total temperature data, which can then be used to simultaneously obtain the total temperature and total pressure data of the incoming flow.

[0071] When in use, place the probe in the flow field to be measured. The incoming flow stops at the end of the synthetic fiber core facing the air inlet. The pressure-sensitive coating measures the total pressure of the incoming flow. The intensity of the excitation light of the pressure-sensitive coating and the pressure satisfy the following relationship:

[0072]

[0073] Where I represents light intensity, P represents pressure, the subscript ref represents the reference state, and A and B are related coefficients. By calibration, the relationship between light intensity and pressure can be obtained, and then the total pressure of the incoming flow can be calculated.

[0074] The airflow completely converts kinetic energy into thermal energy at the core of the synthetic end sprayed with the temperature-sensitive coating. The temperature-sensitive coating measures the total temperature of the incoming flow. The excitation light intensity and temperature of the temperature-sensitive coating satisfy the following relationship:

[0075]

[0076] Where I represents light intensity, T represents pressure, and the subscript ref represents the reference state. Function f can be calibrated to fit the relationship between light intensity and temperature using polynomial, exponential, and other functional forms, thereby obtaining the total temperature of the incoming flow.

[0077] The signal transmitting unit includes a light source 022 and a signal generator 021, which are used to excite the pressure-sensitive coating 7 and the temperature-sensitive coating 8. The light source 022 is an ultraviolet laser or a blue laser with a wavelength range of 260nm-600nm. In this embodiment, 405nm is selected, with a power of 15W, a pulse width of 20ms, and a pulse period of 1000ms.

[0078] The pressure signal receiving unit 03 includes a pressure signal bandpass optical filter 031 and a pressure signal light detector 032. The pressure signal bandpass optical filter 031 is used to filter out background light and non-pressure optical signals. The pressure signal light detector 032 is a photodiode or a photomultiplier tube. In this embodiment, a photomultiplier tube is used.

[0079] The temperature signal receiving unit 04 includes a temperature signal bandpass optical filter 041 and a temperature signal light detector 042. The temperature signal bandpass optical filter 041 is used to filter out background light and non-temperature optical signals. The temperature signal light detector 042 is a photodiode or a photomultiplier tube. In this embodiment, a photomultiplier tube is used.

[0080] The pressure signal processing unit 05 is used to process the pressure optical signal output by the pressure signal light detector 032 and calculate the light intensity ratio to obtain pressure information.

[0081] The temperature signal processing unit 06 is used to process the temperature optical signal output by the temperature signal light detector 042 and calculate the light intensity ratio to obtain temperature information.

[0082] Preferably, the probe further includes a calibration system for regularly calibrating the pressure response characteristics of the pressure-sensitive coating 7 and the temperature response characteristics of the temperature-sensitive coating 8 .

[0083] This embodiment employs fluorescence pressure measurement and fluorescence temperature measurement, utilizing the pressure-sensitive or temperature-sensitive properties of fluorescent materials to calculate pressure or temperature by detecting the intensity or decay time of fluorescence. This measurement method offers the advantages of high sensitivity and precision, and can achieve pressure and temperature measurement in a characteristic region by spraying pressure-sensitive or temperature-sensitive fluorescent materials onto the surface of the object to be measured. This embodiment combines fluorescence pressure measurement and fluorescence temperature measurement technologies, using a fluorescent fiber-based probe to meet flow field measurement requirements. This integrates pressure-sensitive and temperature-sensitive coatings, leveraging the advantages of fiber optic sensors. While offering the advantages of optical measurement's resistance to electromagnetic interference and compact size, it can also achieve simultaneous measurement of total temperature and total pressure in the same region.

[0084] The working process of this system includes the following steps:

[0085] (1) Place the total temperature and total pressure synchronous measurement probe 01 based on fluorescent optical fiber in the flow field to be measured, so that the air inlet 3 faces the direction of the incoming and outgoing flow;

[0086] (2) The laser light emitted by the signal transmitting unit 02 is incident on the optical fiber combining end 11 through the optical fiber input end 12, and is used to excite the pressure-sensitive coating 7 and the temperature-sensitive coating 8;

[0087] (3) The high-speed airflow stops at the synthetic end core 6 of the sprayed pressure-sensitive coating 7 facing the air inlet 3. The pressure-sensitive coating 7 is excited by the input light, generating excitation light carrying pressure information and outputting it through the first output end 13 of the optical fiber. The excitation light is then transmitted to the pressure signal processing unit 05 through the pressure signal receiving unit 03.

[0088] (4) The high-speed airflow completely converts kinetic energy into thermal energy at the fiber core 6 at the synthesis end where the temperature-sensitive coating 8 is sprayed. The temperature-sensitive coating 8 is excited by the input light, generates excitation light carrying temperature information, and outputs it through the second output end 14 of the optical fiber, and then transmits it to the temperature signal processing unit 06 through the temperature signal receiving unit 04;

[0089] (5) The pressure signal processing unit 05 and the temperature signal processing unit 06 process the synchronous optical signals carrying pressure and temperature information respectively, and then obtain the total temperature and total pressure data of the flow field.

[0090] This method / system has the following beneficial effects:

[0091] (1) After temperature and pressure calibration, a single optical fiber can be used to achieve synchronous measurement of total temperature and total pressure at the same position in the flow field, providing an efficient and accurate means for flow field testing.

[0092] (2) The probe is designed with multiple air inlets in a cross shape, which makes the probe measurement results insensitive to the incoming flow in a large angular range and is almost unaffected by the incoming flow direction.

[0093] (3) The probe makes full use of the flow characteristics of the air after passing through the air inlet. The pressure stagnation effect is best at the point directly opposite the air inlet, and the temperature stagnation heat exchange effect is best at the lower end of the air inlet. The layout of spraying pressure-sensitive material at the point directly opposite the air inlet and spraying temperature-sensitive material at the lower end of the air inlet makes the measurement results more accurate and the measurement accuracy is high.

[0094] (4) The probe head has a simple structure and a small size, which significantly improves the spatial resolution of the measurement, enabling measurement in various narrow spaces with little interference to the flow field.

[0095] (5) The probe is based on fluorescent fiber measurement and is not affected by electromagnetic interference, measurement environment humidity, etc., and is applicable to a wide range of measurement environments.

[0096] Example 2

[0097] See also Figure 10 This embodiment provides an electronic device, which includes a processor, an internal bus, a network interface, a memory, and a non-volatile memory at the hardware level, and may also include hardware required for other services. The processor reads the corresponding computer program from the non-volatile memory into the memory and then runs it to achieve the above Figure 1 The method for synchronous measurement of total temperature and total pressure.

[0098] Example 3

[0099] This embodiment provides a computer-readable storage medium, including one or more programs for execution by one or more processors of an electronic device, wherein the one or more programs include a method for executing the following: Figure 1 Instructions for the method of synchronous measurement of total temperature and total pressure.

[0100] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and such modifications or substitutions are intended to be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A method for synchronously measuring total temperature and total pressure based on fluorescent optical fiber, characterized in that: The steps include: Step S1, generating an excitation light signal and inputting it into a synthetic end fiber core arranged on the airflow path to be measured, wherein the outer side of the synthetic end fiber core includes a temperature sensitive coating and a pressure sensitive coating; Step S2, obtaining a mixed light signal generated by the airflow to be measured passing through the temperature-sensitive coating and the pressure-sensitive coating; Step S3: filtering the mixed optical signal to obtain a temperature optical signal and a pressure optical signal, and obtaining total temperature information and total pressure information of the flow field by calculating the light intensity ratio.

2. A total temperature and total pressure synchronous measurement system based on fluorescent optical fiber, characterized in that: For realizing the total temperature and total pressure synchronous measurement method based on fluorescent optical fiber as claimed in claim 1, the total temperature and total pressure synchronous measurement system comprises: A probe head (1) is provided with a channel (5) in the axial direction, and an air inlet (3) and an air outlet (4) are provided on the probe head (1); A synthetic end fiber core (6) is fixed in the channel (5), and the outer side of the synthetic end fiber core (6) includes a temperature-sensitive coating (8) and a pressure-sensitive coating (7); A signal transmitting unit (02), used for generating an excitation light signal and inputting the excitation light signal into the synthesis end fiber core (6); A pressure signal receiving unit (03) is used to collect a mixed optical signal generated by the airflow to be measured passing through the temperature-sensitive coating (8) and the pressure-sensitive coating (7), and filter to obtain an optical signal matching the optical wavelength of the pressure-sensitive coating (7); A temperature signal receiving unit (04) is used to collect a mixed optical signal generated by the airflow to be measured passing through the temperature-sensitive coating (8) and the pressure-sensitive coating (7), and filter to obtain an optical signal matching the wavelength of the light of the temperature-sensitive coating (8); The pressure signal processing unit (05) and the temperature signal processing unit (06) are used to synchronously process the optical signal matching the optical wavelength of the pressure-sensitive coating (7) and the optical signal matching the optical wavelength of the temperature-sensitive coating (8), respectively, to obtain the total temperature information and the total pressure information of the flow field.

3. The total temperature and total pressure synchronous measurement system based on fluorescent optical fiber according to claim 2 is characterized in that: The temperature-sensitive coating (8) and the pressure-sensitive coating (7) are arranged at intervals, and the pressure-sensitive coating (7) faces the air inlet (3).

4. The total temperature and total pressure synchronous measurement system based on fluorescent optical fiber according to claim 2 is characterized in that: The invention comprises a plurality of the air inlet holes (3), wherein the air inlet holes (3) are directly facing the main flow measurement and are in a cross shape with the center line of the center hole as the axis of symmetry, the center line of the center hole is 0.8 mm to 5 mm away from the top of the probe head (1), the center lines of the holes arranged along the circumferential direction are perpendicular to the axis of the cylinder and intersect at the center of the circumferential cylindrical surface, the angle between adjacent circumferential holes is 15° to 60°, the center lines of the holes arranged along the axial direction intersect at the leeward measuring point of the circumferential cylindrical surface where the center line of the center hole is located, and the angle between adjacent axial holes is 5° to 30°.

5. The total temperature and total pressure synchronous measurement system based on fluorescent optical fiber according to claim 2 is characterized in that: It comprises a plurality of the air outlet holes (4), wherein the air outlet holes (4) are arranged along the circumferential direction, the center lines of the air outlet holes (4) are parallel and perpendicular to the axis of the cylinder, and the distance between the center lines of the air outlet holes (4) and the top of the probe head is 6 mm-16 mm.

6. The total temperature and total pressure synchronous measurement system based on fluorescent optical fiber according to claim 2 is characterized in that: The pressure-sensitive coating (7) is a porous ceramic pressure-sensitive coating or a mesoporous ceramic pressure-sensitive coating, and the temperature-sensitive coating (8) is MFG, Y2O3:Eu, YSZ:Eu, YVO4:Dy or YAG:Dy.

7. The total temperature and total pressure synchronous measurement system based on fluorescent optical fiber according to claim 2 is characterized in that: The signal transmitting unit (02) comprises a signal generator (021) and a light source (022).

8. The total temperature and total pressure synchronous measurement system based on fluorescent optical fiber according to claim 2 is characterized in that: The pressure signal receiving unit (03) comprises a pressure signal bandpass optical filter (031) and a pressure signal light detector (032) connected in sequence, and the temperature signal receiving unit (04) comprises a temperature signal bandpass optical filter (041) and a temperature signal light detector (042) connected in sequence.

9. The total temperature and total pressure synchronous measurement system based on fluorescent optical fiber according to claim 2 is characterized in that: The total temperature and total pressure synchronous measurement system also includes: The optical fiber coupler (15) is connected to the signal transmitting unit (02) via the optical fiber input end (12), is connected to the pressure signal receiving unit (03) and the temperature signal receiving unit (04) via the optical fiber first output end (13) and the optical fiber second output end (14), and is connected to the synthetic end fiber core (6) via the optical fiber synthetic end (11).

10. The total temperature and total pressure synchronous measurement system based on fluorescent optical fiber according to claim 2, characterized in that: The total temperature and total pressure synchronous measurement system also includes: The synthetic end shell (9) encloses one end of the synthetic end fiber core (6), and the synthetic end shell (9) is in contact with the probe head (1) via an insulating glue (10).

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