Aircraft surface temperature field and pressure field coupling measurement method and system based on phosphorescent coating

Abstract

The invention discloses an aircraft surface temperature field and pressure field coupling measurement method and system based on a phosphorescent coating, and relates to the technical field of aircraft surface temperature field and pressure field coupling measurement, and the method comprises the steps: firstly, exciting a phosphorescent coating coated on the surface of an aircraft by using pulse laser; secondly, phosphorescence images of two different characteristic emission wavebands radiated by the phosphorescence coating after excitation are collected; then, calculating an intensity ratio based on the phosphorescence images of the two characteristic emission wavebands; then determining a temperature field of the aircraft surface based on the intensity ratio; meanwhile, the phosphorescence lifetime is calculated through a phosphorescence attenuation image of one characteristic emission wave band; and finally, determining a pressure field on the surface of the aircraft by combining the known temperature field and the phosphorescence lifetime, and realizing synchronous decoupling measurement of the temperature field and the pressure field. According to the invention, the YAG: Dy phosphorescent coating is adopted, real synchronous testing of a temperature field and a pressure field is realized by using single dysprosium ions, stable work in an extreme high-temperature environment can be realized, and the measurement precision is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of coupled temperature and pressure field measurement technology for aircraft surfaces, and particularly to a method and system for coupled measurement of temperature and pressure fields on aircraft surfaces based on phosphorescent coatings. Background Technology

[0002] In the field of high-speed aircraft design and testing, surface temperature and pressure are key physical parameters that are strongly coupled, together forming the basis of the aircraft's thermal environment. Among them, pressure data is the core input for analyzing aerodynamic performance and evaluating structural strength, while temperature data is the fundamental basis for designing thermal protection systems.

[0003] During high-speed flight, the temperature and pressure fields exhibit a deep and bidirectional interaction. On one hand, the surface temperature distribution alters the density and viscosity of the air within the boundary layer, directly affecting the pressure field distribution. On the other hand, pressure field fluctuations significantly influence the temperature distribution; for example, when an aircraft traverses a shock wave, the local pressure rises sharply, causing a surge in heat flux density at the wall surface and creating specific high-temperature regions. Furthermore, in hypersonic environments, high temperatures induce real gas effects such as air dissociation or ionization, altering fluid physical properties and making the coupling mechanism between temperature and pressure extremely complex, involving a deep interweaving of thermodynamic and chemical kinetic coupling.

[0004] Given the complex coupling relationship mentioned above, it is crucial to achieve simultaneous testing of the temperature and pressure fields on the surface of the aircraft. Simultaneous testing can accurately capture the instantaneous interaction and changes between the two, precisely control the true physical state of the aircraft, and provide a reliable basis for safe, efficient and advanced design.

[0005] Existing measurement schemes based on phosphorescent coatings attempt to address the problem of synchronous testing, but they have significant drawbacks. These schemes employ phosphorescent coatings doped with multiple ions, measuring temperature and pressure fields in stages. This results in time intervals between measurements, making them unsuitable for rapidly changing transient processes, as the physical state of the aircraft surface may change drastically during these intervals. Furthermore, non-radiative energy transfer occurs between different ions within the coating, interfering with the accuracy of key parameter measurements, such as affecting the luminescence lifetime readings of specific ions. In addition, reliance on multiple optical acquisition devices, such as strictly synchronized dual-camera systems, increases system complexity and the risk of temporal and spatial alignment errors. Finally, the coating's applicable temperature range is limited, operating only within a moderate temperature range, failing to meet the testing requirements of ultra-high temperature environments (such as the surfaces of hypersonic aircraft), and is susceptible to factors such as pressure and high-temperature-induced luminescence decay, reducing test accuracy and reliability. Summary of the Invention

[0006] In view of this, the present invention proposes a method and system for coupled measurement of temperature and pressure fields on the surface of an aircraft based on phosphorescent coating, in order to solve the problem of coupling error that easily occurs in the joint measurement of temperature and pressure fields on the surface of an aircraft in the prior art.

[0007] The specific technical solution of this invention is as follows: A method for coupled measurement of temperature and pressure fields on the surface of an aircraft based on a phosphorescent coating, comprising: First, a pulsed laser is used to excite the phosphorescent coating on the surface of the aircraft; Secondly, phosphorescent images of two different emission bands emitted by the phosphorescent coating after laser excitation were acquired; Next, the intensity ratio is calculated based on the phosphorescence images of the two characteristic emission bands; Then, the temperature field on the surface of the aircraft is determined based on the intensity ratio; at the same time, the phosphorescence lifetime is calculated by phosphorescence attenuation image of one of the characteristic emission bands. Finally, by combining the known temperature field and phosphorescence lifetime, the pressure field on the aircraft surface is determined, thus achieving synchronous decoupled measurement of the temperature and pressure fields.

[0008] Specifically, the phosphorescent coating is a yttrium aluminum garnet-doped dysprosium ion coating, which utilizes a single dysprosium ion luminescence center to generate a phosphorescent signal that is sensitive to temperature and pressure, thus avoiding energy transfer interference in multi-ion systems.

[0009] Specifically, the two characteristic emission bands include a first characteristic emission band and a second characteristic emission band, wherein the ratio of the phosphorescence intensity of the first characteristic emission band to the phosphorescence intensity of the second characteristic emission band is only sensitive to temperature and is independent of pressure.

[0010] Specifically, the intensity ratio is mapped to temperature values ​​based on the Boltzmann distribution relationship, where the intensity ratio changes with temperature in accordance with a preset calibration function.

[0011] Specifically, phosphorescence lifetime is affected by both temperature and pressure. Under known temperature conditions, the pressure field can be independently analyzed by the mapping relationship between phosphorescence lifetime and pressure.

[0012] Specifically, the method also includes a calibration step: establishing a single mapping relationship between intensity ratio and temperature in a controlled temperature and pressure environment, as well as a multivariate mapping relationship between phosphorescence lifetime and temperature and pressure, for parameter calculation in subsequent measurements.

[0013] Specifically, the acquisition process is performed using a single binocular camera, which simultaneously captures phosphorescent images of two characteristic emission bands to ensure spatiotemporal synchronization.

[0014] Specifically, the excitation of the pulsed laser and the camera exposure are coordinated by a signal synchronizer to ensure accurate capture of the phosphorescence decay process under high-frequency pulses.

[0015] Specifically, the method operates stably under extreme high-temperature conditions, and the high-temperature phase stability of the coating matrix enhances the thermal quenching resistance of dysprosium ions.

[0016] A coupled measurement system for the temperature and pressure fields of an aircraft surface based on a phosphorescent coating includes a signal synchronizer, a pulsed laser, a beam splitter, a reflector, a dichroic mirror, a filter group, a dual-frame camera, and a computer. The signal synchronizer connects the pulsed laser and the dual-frame camera to generate a unified timing signal. The excitation light emitted by the pulsed laser is split by the beam splitter; part of the light is monitored by a power meter, and the remaining light is guided to the dichroic mirror by the reflector. The dichroic mirror reflects the excitation light to the phosphorescent coating and transmits the phosphorescent signal radiated by the coating. The phosphorescent signal is split into two paths by another beam splitter, and after passing through the filter group to filter out stray light, they enter the two lenses of the dual-frame camera to capture images of different emission bands. The computer processes the image data to calculate the intensity ratio and phosphorescence lifetime, realizing the synchronous decoupled measurement of the temperature and pressure fields.

[0017] The beneficial effects of this invention are as follows: (1) By using the difference in luminescence characteristics of dysprosium ions in a specific thermal coupling energy level in the yttrium aluminum garnet doped dysprosium ion phosphorescent coating to achieve signal separation mechanism, synchronous decoupling measurement of temperature field and pressure field is realized, effectively avoiding the time delay error of traditional step measurement, and significantly improving the monitoring accuracy of high-speed maneuvering transient process of aircraft. (2) Based on the temperature and pressure signal generation mechanism of a single dysprosium ion luminescence center, the inherent energy transfer interference and chemical environment interference of multi-ion systems are avoided, and the intrinsic accuracy of the measurement data is guaranteed from the signal source level; (3) The design of using a single binocular camera in conjunction with an integrated optical acquisition path reduces system complexity and hardware costs while completely solving the problem of spatial registration error in multi-device collaboration. (4) Relying on the high-temperature phase stability of the yttrium aluminum garnet matrix, the thermal quenching resistance of the dysprosium ion luminescence center is enhanced, ensuring the long-term stability of the measurement method under extreme high-temperature conditions such as hot-end components of aero-engines, and broadening the applicable boundaries in the field of aerospace thermodynamic testing. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application, 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 of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic flowchart of the YAG:Dy phosphorescent coating preparation method of the present invention; Figure 2 This is a schematic diagram of the structure of the coupled measurement system for temperature and pressure fields on the surface of an aircraft based on phosphorescent coating, according to the present invention. Figure 3This is a schematic diagram of the strength ratio-temperature calibration curve of the present invention; Figure 4 This is a schematic diagram illustrating the mapping relationship between phosphorescence lifetime and pressure under different temperature conditions according to the present invention. Figure 5 This is a schematic flowchart of the method for coupled measurement of temperature and pressure fields on the surface of an aircraft based on phosphorescent coating, according to the present invention. Figure 6 This is a schematic diagram of the data processing for coupled measurement of temperature and pressure fields in this invention. Detailed Implementation

[0020] To make the technical problems, solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0021] This invention proposes a method and system for coupled measurement of temperature and pressure fields on the surface of aircraft based on phosphorescent coatings. The core of this method lies in utilizing the properties of rare-earth ion-doped phosphorescent materials to achieve simultaneous decoupled measurement of temperature and pressure through a single excitation source and optical acquisition system. This method innovatively employs a phosphorescent coating of yttrium aluminum garnet doped with dysprosium ions, namely a YAG:Dy phosphorescent coating. The luminescence behavior of dysprosium ions at specific wavelengths exhibits different sensitivities to temperature and pressure, thus enabling high-precision coupled measurement under a single experimental condition. Specifically, this method measures the Dy content in the YAG:Dy phosphorescent coating... 3+ Temperature field information is independently obtained by comparing the intensity ratio of characteristic emission peaks in the 458 nm and 484 nm bands. Simultaneously, phosphorescence lifetime data in the 458 nm band is combined to analyze pressure field information based on the known temperature field. This design effectively avoids errors caused by temperature-pressure coupling in traditional methods, simplifies the system structure, and significantly improves measurement accuracy, providing a reliable technical means for real-time monitoring of aircraft surface conditions.

[0022] The preparation of the phosphorescent coating YAG:Dy is fundamental to this method, and its quality directly affects the measurement accuracy. For example... Figure 1 As shown, firstly, yttrium nitrate, dysprosium nitrate, and aluminum nitrate must be accurately weighed according to a specific stoichiometric ratio, and an appropriate amount of deionized water is added to prepare a metal ion solution with a concentration of 0.8 mol / L. Simultaneously, a measured amount of ammonium bicarbonate is weighed to prepare a 2.5 mol / L precipitant solution, and the surfactant ammonium sulfate is added to this solution, with the mass ratio strictly following m((NH4)2SO4):m(Al2O3). 3+The reaction was performed at a ratio of 0.4. The solution was then stirred uniformly at 40°C for 4 hours to ensure thorough mixing. Next, the metal ion solution and precipitant solution were titrated together into a third-party beaker using a peristaltic pump. The titration rate of the metal ion solution was controlled at 5 mL / min, and the titration rate of the precipitant was controlled at 6 mL / min, while the reaction temperature was maintained at 25°C. After the reaction was complete, the titration was stopped, and stirring was continued for 1 hour to promote reaction equilibrium. Then, stirring was stopped, and the mixture was aged for 12 hours to allow the precipitate particles to grow and stabilize. After aging, the white precipitate slurry was thoroughly washed, first twice with deionized water to remove most soluble impurities, and then twice with anhydrous ethanol to further remove residual water and organic residues. The washed precipitate was placed in a drying oven and dried at 100°C until a dry white powder precursor was obtained. The precursor was then transferred to a box-type atmosphere furnace for calcination at 900°C for 2 hours. After calcination, the product was finely ground to obtain uniform phosphorescent thermometric powder. Next, the phosphorescent thermometric powder was mixed with polyethersulfone and the solvent N-methyl-2-pyrrolidone in a specific ratio to form a slurry. A suitable amount of slurry was placed in a micro-injection pump syringe, and the slurry was dripped from the needle hole through parameter settings, dispersing into tiny droplets that entered a water-containing container. The droplets precipitated as a solid phase in the water, forming white powder particles. Finally, the phosphorescent particles were subjected to atmospheric plasma spraying (APS) treatment. The spraying parameters included a spraying voltage of 200V, a spraying current of 300A, an argon flow rate of 150 L / min, and a hydrogen flow rate of 65 L / min, ensuring a uniform and dense coating adhered to the aircraft surface, providing a stable response for subsequent measurements.

[0023] The measurement principle is the scientific basis of the entire method, based on the Dy content in the YAG:Dy phosphorescent coating. 3+ The luminescent properties. The temperature measurement principle relies on Dy 3+ The intensity ratio of the characteristic emission peak in the 458 nm and 484 nm bands ( FIR Only for temperature ( T Sensitive to stress P Unrelated properties. The intensity ratio and temperature follow the Boltzmann distribution relationship: ; In the formula, FIR The ratio of phosphorescence intensity at a wavelength of 458 nm to phosphorescence intensity at a wavelength of 484 nm. I 1 and I 2 The phosphorescence intensities at wavelengths of 458 nm and 484 nm, respectively. ΔEThe energy level difference of the thermally coupled energy levels corresponding to wavelengths of 458 nm and 484 nm. k B Boltzmann's constant, T For temperature, B and C All of these are fitting constants.

[0024] The pressure measurement principle is based on the Dy in the YAG:Dy phosphorescent coating. 3+ Phosphorescence lifetime at 458 nm ( τ ) affected by temperature ( T ) and pressure ( P The characteristics of the combined effects, pressure measurement is based on the Dy phosphorescent coating of YAG:Dy. 3+ Phosphorescence lifetime at 458 nm ( τ ) affected by temperature ( T ) and pressure ( P The combined effects of these factors affect its lifespan ( τ ) is also temperature ( T ) and pressure ( P The function of ) τ = f(P, T) ; As can be seen from this formula, under the condition that the temperature is known, the change in lifespan can be independently mapped to the pressure value.

[0025] This invention selects Dy from the YAG:Dy phosphorescent coating 3+ A specific phosphorescence wavelength is used to decouple temperature and pressure measurements. The innovation of this temperature-pressure decoupling method lies in its wavelength selection strategy. During calibration, a thermally coupled energy level combination of 458 nm and 484 nm is chosen to establish a single mapping relationship between the intensity ratio and temperature; this intensity ratio depends only on temperature. Simultaneously, a multivariate mapping relationship between phosphorescence lifetime and pressure and temperature is established using the 458 nm band. Through this decoupling design, the temperature signal is directly obtained from the intensity ratio and used to eliminate temperature interference in the lifetime signal, thereby independently resolving the pressure signal and avoiding cross-influence.

[0026] The construction of the measurement system of this invention provides the hardware guarantee for achieving collaborative measurement, such as... Figure 2As shown, the system includes components such as a signal synchronizer, a 100 kHz pulsed laser, a beam splitter, a power meter, a reflector, a dichroic mirror, filters, a dual-frame camera, and a computer. The signal synchronizer is connected to both the pulsed laser and the dual-frame camera to generate a unified timing control signal, precisely coordinating the timing synchronization between laser emission and camera exposure. The pulsed laser operates at a frequency of 100 kHz, emitting high-frequency pulsed laser light to excite the phosphorescent coating. Beam splitter 1 is used to split the laser beam path onto the surfaces of the power meter and reflector 1, with a splitting ratio of 1:9. The power meter monitors the stability of the excitation light in real time. Reflector 1 guides the laser to the dichroic mirror, which has wavelength-selective transmittance, reflecting short-wavelength laser light and transmitting long-wavelength phosphorescence. The light signal emitted after the phosphorescent coating is excited is guided by a dichroic mirror to a beam splitter 2. The beam splitter 2 divides the light path into two channels: one channel passes through a reflector 2 and a filter 1, transmitting only the 458 nm phosphorescent signal into the lens 1 of the dual-frame camera; the other channel passes through the filter 2, transmitting only the 484 nm phosphorescent signal into the lens 2. The spatial positions of the reflector 1, dichroic mirror, beam splitter 2, filter group, and dual-frame camera are relatively fixed, ensuring that the 458 nm and 484 nm signals emitted from the phosphorescent coating enter the camera through the same optical path length, thus guaranteeing strict spatial synchronization and registration of the two channels. The filter is used to filter out residual laser light in the phosphorescence. The dual-frame camera converts the two wavelength signals into phosphorescent image electrical signals, which are then transmitted to a computer for processing. During system operation, the signal synchronizer first triggers the laser to emit a pulse, and then triggers the camera exposure after a preset delay, ensuring accurate capture of the phosphorescent attenuation signal. The entire system requires only a single laser and a single binocular camera, resulting in a compact structure and reduced spatial synchronization errors and costs.

[0027] Calibration is a crucial preprocessing step to ensure measurement accuracy and must be performed on a dedicated calibration device. This device includes high-precision standard temperature and pressure sensors, a controllable temperature and pressure chamber, and an excitation and optical acquisition system consistent with the measurement system. Calibration aims to establish two core mapping relationships: a single function of phosphorescence intensity ratio and temperature. R = g(T) And the multivariate functional relationship between phosphorescence lifetime and pressure and temperature. τ = f(P, T) .

[0028] The calibration process for the intensity ratio versus temperature relationship is as follows: The prepared YAG:Dy phosphorescent coating sample is installed in the clean optical window of the calibration chamber, and a standard thermocouple is connected so that its temperature measuring end is in close contact with the coating surface; the chamber pressure is kept constant, and the temperature is gradually increased from room temperature to the target maximum value. The standard temperature value is recorded after each temperature point stabilizes; at each temperature... T Below, a pulsed laser is used to excite the phosphorescent coating, and a dual-frame camera simultaneously acquires phosphorescent images in the 458 nm and 484 nm wavelength bands to obtain the light intensity distribution. and And calculate the intensity ratio at each temperature: ; Fit a Boltzmann distribution function to all temperature data points to obtain a constant. B , C and energy level difference ΔE The strength ratio was obtained. R The exact mapping relationship with temperature: R = g(T) ; The calibration curve is as follows: Figure 3 As shown, the cavity pressure remains constant throughout the process.

[0029] The calibration process for the relationship between lifespan and pressure / temperature is as follows: Step 1: Install the prepared YAG:Dy phosphorescent coating sample in the clean optical window of the calibration cavity, and ensure that the measuring end of the standard thermocouple is in good contact with the coating surface for accurate temperature measurement. The standard pressure sensor is used to monitor the cavity pressure. Step 2: Maintain the cavity temperature at the precise temperature value recorded by the standard sensor. T 1 Then the pressure in the control chamber was gradually increased to P 1 , P 2 , P 3 , ... P n At each pressure point Once the pressure has stabilized, record the readings from the standard pressure sensor. P j ; Step 3, at each pressure point After stabilization, the coating was excited using a pulsed laser, and phosphorescence attenuation images were acquired through the 458 nm channel of a dual-frame camera to calculate the state. Phosphorescence lifetime value ; Step 4: Change the cavity temperature to the next target temperature point. T 2 Repeat steps 2 and 3, and so on, until the temperature reaches the target value. T i ; Step 5, collect data from all states ( T i , P j , τ ij ), constructing phosphorescence lifetime τ With pressure P and temperatureT Mapping relationship between τ = f ( P, T ).like Figure 4 As shown.

[0030] The measurement method of this invention is based on the aforementioned coating, principle, system, and calibration data, such as... Figure 5-6 As shown. Step 1: Control the laser source to emit a pulsed laser with a pulse frequency of 100 kHz via a signal generator, where the laser source wavelength is 355 nm; Step 2: Trigger the signal to expose the image after a preset delay time using a dual-frame camera, so as to accurately capture the phosphorescent images emitted by the phosphorescent coating excited by the pulsed laser at wavelengths of 458 nm and 484 nm. Step 3: Calculate the phosphorescent intensity ratio of 458 nm and 484 nm using the synchronously acquired phosphorescent images at wavelengths of 458 nm and 484 nm. FIR The phosphorescence lifetime at 458 nm was calculated using the acquired 458 nm phosphorescence image. τ Step 4: Based on the measured phosphorescence intensity ratio FIR Calculate the phosphorescent coating temperature based on the intensity-temperature mapping relationship. T Step 5: Based on the phosphorescent coating temperature calculated in Step 4 T A calibration curve of phosphorescence lifetime versus pressure at a specific temperature was selected, combined with experimentally measured phosphorescence lifetime. τ Calculate the pressure of the phosphorescent coating. P The entire process is completed under a single excitation event, ensuring that temperature and pressure data are synchronized in time and space.

[0031] The beneficial effects of this invention are as follows: (1) By separating the luminescence characteristics of dysprosium ions in a specific thermally coupled energy level in the yttrium aluminum garnet-doped dysprosium ion phosphorescent coating, the synchronous decoupling measurement of temperature field and pressure field is realized, effectively avoiding the time delay error of traditional step measurement, and significantly improving the monitoring accuracy of the transient process of high-speed maneuvering of aircraft. (2) Based on the temperature and pressure signal generation mechanism of a single dysprosium ion luminescence center, the inherent energy transfer interference and chemical environment interference of multi-ion systems are avoided, and the intrinsic accuracy of the measurement data is guaranteed from the signal source level; (3) The design of using a single binocular camera in conjunction with an integrated optical acquisition path reduces system complexity and hardware costs while completely solving the problem of spatial registration error in multi-device collaboration. (4) Relying on the high-temperature phase stability of the yttrium aluminum garnet matrix, the thermal quenching resistance of the dysprosium ion luminescence center is enhanced, ensuring the long-term stability of the measurement method under extreme high-temperature conditions such as hot-end components of aero-engines, and broadening the applicable boundaries in the field of aerospace thermodynamic testing.

[0032] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for coupled measurement of temperature and pressure fields on the surface of an aircraft based on a phosphorescent coating, characterized in that, include: First, a pulsed laser is used to excite the phosphorescent coating on the surface of the aircraft; Secondly, phosphorescent images of two different emission bands emitted by the phosphorescent coating after laser excitation were acquired; Next, the intensity ratio is calculated based on the phosphorescence images of the two characteristic emission bands; Then, the temperature field on the surface of the aircraft is determined based on the intensity ratio; at the same time, the phosphorescence lifetime is calculated using a phosphorescence attenuation image of one of the characteristic emission bands. Finally, the pressure field on the aircraft surface is determined by combining the known temperature field and the phosphorescence lifetime, thus achieving synchronous decoupled measurement of the temperature field and the pressure field.

2. The method for coupled measurement of temperature and pressure fields on the surface of an aircraft based on phosphorescent coating as described in claim 1, characterized in that, The phosphorescent coating is a yttrium aluminum garnet-doped dysprosium ion coating, which uses a single dysprosium ion luminescent center to generate a phosphorescent signal that is sensitive to temperature and pressure, thus avoiding energy transfer interference in multi-ion systems.

3. The method for coupled measurement of temperature and pressure fields on the surface of an aircraft based on phosphorescent coating as described in claim 1, characterized in that, The two characteristic emission bands include a first characteristic emission band and a second characteristic emission band, wherein the ratio of the phosphorescence intensity of the first characteristic emission band to the phosphorescence intensity of the second characteristic emission band is only sensitive to temperature and is independent of pressure.

4. The method for coupled measurement of temperature and pressure fields on the surface of an aircraft based on phosphorescent coating as described in claim 3, characterized in that, The intensity ratio is based on the Boltzmann distribution relationship and mapped to the temperature value, wherein the intensity ratio changes with temperature in accordance with a preset calibration function.

5. The method for coupled measurement of temperature and pressure fields on the surface of an aircraft based on phosphorescent coating as described in claim 1, characterized in that, The phosphorescence lifetime is affected by both temperature and pressure. Under known temperature conditions, the pressure field can be independently analyzed by the mapping relationship between phosphorescence lifetime and pressure.

6. The method for coupled measurement of temperature and pressure fields on the surface of an aircraft based on phosphorescent coating as described in claim 1, characterized in that, It also includes calibration steps: establishing a single mapping relationship between intensity ratio and temperature in a controlled temperature and pressure environment, as well as a multivariate mapping relationship between phosphorescence lifetime and temperature and pressure, for parameter calculation in subsequent measurements.

7. The method for coupled measurement of temperature and pressure fields on the surface of an aircraft based on phosphorescent coating as described in claim 1, characterized in that, The acquisition process is performed using a single binocular camera, which simultaneously captures phosphorescent images of two characteristic emission bands to ensure spatiotemporal synchronization.

8. The method for coupled measurement of temperature and pressure fields on the surface of an aircraft based on phosphorescent coating as described in claim 1, characterized in that, The excitation of the pulsed laser and the camera exposure are coordinated by a signal synchronizer to ensure accurate capture of the phosphorescence decay process under high-frequency pulses.

9. The method for coupled measurement of temperature and pressure fields on the surface of an aircraft based on phosphorescent coating as described in claim 1, characterized in that, The method operates stably under extreme high-temperature conditions, and the high-temperature phase stability of the coating matrix enhances the thermal quenching resistance of dysprosium ions.

10. A coupled measurement system for temperature and pressure fields on the surface of an aircraft based on a phosphorescent coating, characterized in that, The system includes a signal synchronizer, a pulsed laser, a beam splitter, a reflector, a dichroic mirror, a filter group, a dual-frame camera, and a computer. The signal synchronizer connects the pulsed laser and the dual-frame camera to generate a unified timing signal. The excitation light emitted by the pulsed laser is split by the beam splitter; part of the light is monitored by a power meter, and the remaining light is guided to the dichroic mirror by the reflector. The dichroic mirror reflects the excitation light to the phosphorescent coating and transmits the phosphorescent signal radiated by the coating. The phosphorescent signal is split into two paths by another beam splitter, and after passing through the filter group to filter out stray light, they enter the two lenses of the dual-frame camera to capture images of different emission bands. The computer processes the image data to calculate the intensity ratio and phosphorescent lifetime, realizing the synchronous decoupled measurement of the temperature field and pressure field.

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