JP2010024395A - Pressure-sensitive coating material, object, and method for measuring surface pressure of object - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure-sensitive coating material which can be easily uniformly applied on the surfaces of various objects and has excellent adherability and high time response, and to provide the object, and a method for measuring the surface pressure of the object. <P>SOLUTION: The pressure sensitive coating material is slurry containing at least one kind of pressure-sensitive material selected from porphyrin-based compounds, ruthenium complexes and aromatic hydrocarbons and solid particles of at least one kind selected from silica, alumina, titanium oxide, ceria, magnesia, zinc oxide and calcium carbonate. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a pressure-sensitive paint and a method for measuring the surface pressure of an object.

  In order to investigate the pressure distribution exerted on aircraft and rocket aircraft, a technology has been developed to apply pressure sensitive paint (PSP) to the surface of aircraft and rocket aircraft models and measure the pressure distribution on the surface in a wind tunnel. (Japanese Unexamined Patent Application Publication No. 2005-29767).

  In pressure distribution measurement using a pressure-sensitive paint, a chemical substance such as porphyrin (PtTFPP, PtOEP, PdTFPP, etc.) having platinum or palladium as a central metal is used as a pressure-sensitive material. The chemical substance emits luminescence (fluorescence / phosphorescence) in the presence of oxygen, and has a property that the emission intensity changes depending on the surrounding oxygen concentration. Therefore, in the pressure distribution measurement using the pressure sensitive paint, the pressure corresponding to the luminescence is detected by measuring the intensity of the luminescence generated by the pressure sensitive material on the model surface. Thereby, a precise pressure distribution can be obtained over the entire surface of the model.

  The pressure measurement using pressure-sensitive paint has the advantage that the pressure distribution on the surface of a three-dimensional object can be obtained easily and can be measured in a non-contact manner, compared with the pressure measurement by a commonly used semiconductor pressure sensor. .

Japanese Patent Application Laid-Open No. 2005-29767 discloses measurement of surface pressure using a pressure-sensitive paint containing a polymer as a binder. However, when a film is formed on the object surface using this pressure-sensitive paint, the pressure-sensitive material on the object surface may be covered with the polymer, and the response speed of the pressure-sensitive material may be low.
JP 2005-29767 A

  The present invention provides a high-speed responsive pressure-sensitive paint that can easily and uniformly coat various object surfaces, has excellent adhesion, and has high pressure sensitivity, and a method for measuring the surface pressure of objects and objects. .

  The pressure-sensitive paint of one embodiment of the present invention is a slurry containing a pressure-sensitive material and solid particles.

  In the pressure-sensitive paint, the solid particles may have an average particle size of 10 nm to 1 μm.

  In the pressure-sensitive paint, the solid particles may be at least one selected from silica, alumina, titanium oxide, ceria, magnesia, zinc oxide, and calcium carbonate.

  In the pressure-sensitive paint, the pressure-sensitive material may be at least one selected from a porphyrin compound, a ruthenium complex, and an aromatic hydrocarbon.

  The method for measuring the surface pressure of an object according to another aspect of the present invention includes a step of forming a film on the surface of the object using the pressure-sensitive paint, a step of measuring the surface pressure of the object including the film, including.

  In the method for measuring the surface pressure of the object, the thickness of the coating film may be 1 μm to 20 μm.

  The object of another embodiment of the present invention has a coating film including a pressure-sensitive material and solid particles having an average particle diameter of 10 nm to 1 μm.

  In the object, the thickness of the coating film may be 1 μm to 20 μm.

  In the above object, the solid particles may be at least one selected from silica, alumina, titanium oxide, ceria, magnesia, zinc oxide, and calcium carbonate.

  In the above object, the pressure sensitive material may be at least one selected from a porphyrin compound, a ruthenium complex, and an aromatic hydrocarbon.

  Since the pressure-sensitive paint is a slurry containing a pressure-sensitive material and solid particles, it can easily and uniformly coat various object surfaces, and can form a film with excellent adhesion and high sensitivity. Therefore, when measuring the surface pressure of the object, it is possible to perform pressure measurement with high accuracy and excellent high-speed response.

  In addition, the pressure-sensitive paint has a porous coating that includes a pressure-sensitive material and solid particles having an average particle diameter of 10 nm to 1 μm, so that the surface pressure can be measured with high accuracy and excellent high-speed response. It is.

  Furthermore, according to the method for measuring the surface pressure of the object, the process of forming a film on the surface of the object using the pressure-sensitive paint makes it possible to easily and easily form a film having excellent adhesion and high sensitivity on various object surfaces. The pressure sensitivity on various object surfaces can be measured with high accuracy and high-speed response by the step of measuring the surface pressure of the object including the coating film, which can be formed uniformly.

  Hereinafter, a pressure-sensitive paint according to an embodiment of the present invention and a method for measuring an object and the surface pressure of the object will be described in detail.

1. Pressure sensitive paint and method for measuring objects and surface pressure of objects 1.1. Pressure-sensitive paint The pressure-sensitive paint of one embodiment of the present invention is a slurry containing a pressure-sensitive material and solid particles.

1.1.1. Pressure-sensitive material The pressure-sensitive material is a compound that emits luminescence (fluorescence / phosphorescence) in accordance with the oxygen partial pressure. Since the oxygen concentration is proportional to the partial pressure in the atmospheric gas, when measuring the pressure on the surface of an object using a pressure sensitive material, the pressure in that region is obtained by measuring the emission intensity in the region where the pressure sensitive material is present. Can do.

  The pressure-sensitive material is preferably at least one selected from, for example, a porphyrin-based compound, a ruthenium complex, and an aromatic hydrocarbon, from the viewpoints of good luminous efficiency and light stability and easy availability. .

Examples of porphyrin compounds include platinum-porphyrin complexes such as PtTFPP and PtOEPP, and palladium-porphyrin complexes such as PdTFPP. Examples of the ruthenium complex include a ruthenium-diphenylphosphine complex such as Ru (dpp) ₃ . Examples of the aromatic hydrocarbon include polycyclic aromatic hydrocarbons such as pyrene.

  The amount of the pressure-sensitive material used in the pressure-sensitive paint of this embodiment is preferably 0.1 to 10% by mass and more preferably 0.3 to 3% by mass with respect to the solid particles. If the amount of the pressure sensitive material used exceeds 10% by mass, the light emission intensity may be saturated and the pressure sensitivity may decrease. On the other hand, if it is less than 0.1% by mass, sufficient light emission intensity may not be obtained. There is. Moreover, it is preferable that a pressure sensitive material exists in the state melt | dissolved in the slurry. If the pressure-sensitive material is not dissolved in the slurry, when the coating is formed on the object surface using the slurry, the pressure-sensitive material is unevenly present on the object surface. It may not be possible.

1.1.2. Solid particles Since the solid particles have a large specific surface area, the surface area (per unit volume) in contact with oxygen is large, and the pressure sensitive material is evenly placed on the surface of the object to which the pressure sensitive paint of this embodiment is applied. The average particle diameter is preferably 10 nm to 1 μm, and more preferably 10 nm to 100 nm, in that it can be performed. When the average particle size exceeds 1 μm, solid particles are likely to be precipitated in the slurry, and the dispersibility of the slurry may be reduced. Further, the adhesion on the object surface is reduced, and the film is easily peeled off. There is.

  The solid particles may be at least one selected from inorganic particles, organic particles, and inorganic-organic composite particles. For example, the solid particles are preferably at least one selected from silica, alumina, ceria, magnesia, titanium oxide (preferably rutile crystals), zinc oxide, and calcium carbonate, and more preferably silica or alumina. preferable.

  The amount of solid particles used in the pressure-sensitive paint of this embodiment is preferably 1 to 30% by mass, more preferably 5 to 20% by mass, and 10 to 15% by mass with respect to the slurry. Is more preferable. If the amount of the solid particles used exceeds 30% by mass, the dispersibility of the solid particles in the paint may be deteriorated. On the other hand, if the amount used is less than 1% by mass, the number of coatings required to form a coating is very high. May increase.

1.1.3. Dispersion medium The pressure-sensitive paint of the present embodiment further includes a dispersion medium for dispersing solid particles. The dispersion medium preferably has a property of dissolving the pressure sensitive material.

  The dispersion medium can be removed from the coating by applying the pressure-sensitive paint of the present embodiment to the object surface and then evaporating the dispersion to dry the coating. Therefore, the dispersion medium preferably has a low boiling point (for example, 150 ° C. or lower).

  Examples of the dispersion medium include at least one selected from the group of alcohol solvents, ketone solvents, amide solvents, ester solvents, and aprotic solvents. For example, the pressure-sensitive material has high solubility. Toluene is preferred because it has a low boiling point and is difficult to cause smears. A dispersion medium can be used 1 type or in combination of 2 or more types.

1.1.4. Other components Although the pressure sensitive paint of this embodiment may contain the polymer, it is preferable that a polymer content rate is small. By forming a paint layer with voids due to the small polymer content of the pressure-sensitive paint of this embodiment, high time responsiveness can be obtained. Here, “the polymer content is small” means that the polymer content in the pressure-sensitive paint is less than 20% by mass. Since the pressure-sensitive paint of this embodiment is a slurry containing a pressure-sensitive material and solid particles, a sufficient amount of pressure-sensitive material can be attached to the object surface via the solid particles even if the polymer content is small. .

1.1.5. Application The pressure-sensitive paint of this embodiment is used for measuring the pressure on the surface of a coating obtained by applying it to the surface of an object. More specifically, the pressure-sensitive paint of this embodiment can easily form a film by spray coating using, for example, an air brush.

  Since the pressure-sensitive paint of the present embodiment does not select the material of the object surface to be applied, for example, a film can be formed on the surface of metal, plastic, wood, or the like. Therefore, it is possible to measure pressure on the surface of an object made of various materials.

  Note that the pressure-sensitive paint of this embodiment may be produced as a slurry containing a pressure-sensitive material and solid particles, or the pressure-sensitive material and solid particles are made into separate units, which are mixed immediately before use. By doing so, the pressure-sensitive paint of this embodiment may be prepared.

1.2. Method for Measuring Surface Pressure of Object The method for measuring the surface pressure of an object according to an embodiment of the present invention includes a step of forming a film on the surface of the object using the pressure-sensitive paint, and a surface pressure of the object including the film. Measuring.

  The surface pressure of the object can be measured by attaching an object (subject, for example, a model) having a film formed using the pressure-sensitive paint of the present embodiment to an ultrasonic wind tunnel and conducting a wind tunnel experiment. In addition, the specific method of a wind tunnel experiment is disclosed by Unexamined-Japanese-Patent No. 2005-29767 and Unexamined-Japanese-Patent No. 2006-10517, for example.

  In the wind tunnel experiment, first, color imaging is performed on the surface of an object having a film with an imaging device (CCD camera) to obtain image information, and surface temperature distribution information is obtained from the intensity distribution of the emission wavelength of the pressure sensitive material in this image information. Next, the entire object surface having a coating is highly accurate by correcting the light emission information of the pressure-sensitive material based on the surface temperature distribution information, if necessary, by correcting the change due to the temperature based on the temperature-sensitive material. Pressure distribution information is obtained.

  In order to measure the pressure on the surface of the object with higher accuracy, the thickness of the formed film is preferably 1 μm to 20 μm, more preferably 2 μm to 15 μm, and further preferably 5 μm to 10 μm. preferable. When the film thickness is less than 1 μm, the amount of light emitted from the paint may be low. On the other hand, when the film thickness exceeds 20 μm, the time responsiveness deteriorates and the film tends to peel off.

1.3. Object An object according to an embodiment of the present invention has a film including the pressure-sensitive material and the solid particles having an average particle diameter of 10 nm to 1 μm. This film can be formed using the pressure-sensitive paint. In order to perform highly accurate pressure measurement, it is preferable that the pressure sensitive material is present on the surface of the solid particles in the coating of the object.

  Here, the object is not particularly limited as long as the measurement of the surface pressure is required, and examples thereof include transportation devices such as vehicles (automobiles, two-wheeled vehicles, trains, etc.), airplanes, and ships. Generally, these transport equipment models are used to measure surface pressure.

2. EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. The present invention is not limited to the following examples.

2.1. Preparation Example 2.1.1. Preparation of Pressure-Sensitive Paint In this example, two types of pressure-sensitive materials (basofen ruthenium (Ru (dpp) ₃ , platinum porphyrin (PtTFPP)) were employed, and three types ((1) SiO _{2 were used} as solid particles. (Average particle size 25 nm), (2) Al ₂ O ₃ (average particle size 31 nm), and (3) Al ₂ O ₃ (average particle size 700 nm)) were employed.

A pressure-sensitive material and solid particles were mixed with an organic solvent (toluene) to prepare a slurry (pressure-sensitive paint). That is, each of the prepared slurries contains (1) a slurry containing 10% by mass of SiO ₂ (average particle size 25 nm) and toluene, and (2) 15% by mass of Al ₂ O ₃ (average particle size 31 nm) and toluene. (3) A slurry containing 15% by mass of Al ₂ O ₃ (average particle size 700 nm) and toluene. Next, the slurry was applied to the substrate using a spray to form a film.

2.1.2. Production of Substrate (Sample) In this example, an aluminum plate (A5052) 10 mm square and 1 mm thick was used as the substrate.

  Before applying the slurry, first, the substrate was degreased. First, the surface of the substrate was wiped with ethanol, and the substrate was immersed in a sodium hydroxide solution (2 wt%) for 5 minutes. Then, it was washed with distilled water and simply dried for 15 minutes in a vacuum oven (about 10 kPa, 60 ° C.). After performing this procedure three times, the substrate was wiped with ethanol.

  An air brush (model name: HP-83C, nozzle diameter: 0.3 mm, manufactured by OLYMPOS) was used for applying the slurry. At that time, the needle adjuster for adjusting the coating amount was set to about 1 rotation, the air pressure was set to 0.8 atm when stationary, and 0.5 atm when coating. As a guide for the amount of ejection, the adjuster should be set so that the ejection trace is a line with a width of about 5 mm. The slurry was applied from a position about 50 mm away from the substrate.

  Unless otherwise specified, the sample obtained by coating is stored in a vacuum oven (model name: AVO-250N, manufactured by ASONE, 60 ° C.) to evaporate the solvent and dry to obtain a substrate having a coating on the surface. It was. This substrate was used as a sample for the following test.

2.2. Test method 2.2.1. Static Evaluation Test In order to evaluate the light emission characteristics, pressure characteristics, and temperature characteristics, the calibration test apparatus 20 shown in FIG. 1 was used. As shown in FIG. 1, the calibration test apparatus 20 is installed in a dark room 10, and is a cooled CCD camera 11 (model name: C4880-5024W, manufactured by Hamamatsu Photonics), which is an imaging apparatus, a light source 12, and pressure and temperature. Including a controllable chamber 13. The light source 12 includes a xenon lamp with a band pass (for Ru (dpp) ₃ , transmission wavelength: 460 ± 50 nm) and a laser diode (for PtTFPP, wavelength: 400 nm, model name: RV) according to the excitation wavelength of the pressure-sensitive material. -1000, manufactured by Ricoh Optical Co., Ltd.). In addition, a band pass filter 19 (620 ± 50 nm) was installed in front of the CCD camera 11 to block light other than near the emission wavelength band of the pressure sensitive material. The temperature and pressure were changed between 10 to 40 ° C. and 10 to 100 kPa, respectively, and the emission intensity under each condition was measured.

2.2.2. Time Response Test In order to evaluate the time response to a step pressure change, the shock tube 30 shown in FIG. 2 was used. As shown in FIG. 2, the shock tube 30 is mainly composed of a high pressure chamber 24 (1 m, Φ38 mm), a low pressure chamber 25 (2 m, Φ38 mm), and a test section 29 (0.2 m, flow path 34 mm × 34 mm). The In the shock wave tube 30, the diaphragm 21 (Lumilla membrane (12 μm × 2), manufactured by Toray Industries, Inc.) installed between the high-pressure chamber 24 and the low-pressure chamber 25 is broken by energization heating of nichrome wire sandwiched between the membranes. Thus, a shock wave is generated in the low pressure chamber 25. The test section 29 is made of acrylic, and a sample (substrate having a coating) 14 and a semiconductor pressure sensor 28 (model name: XTL-140, manufactured by Kulite) are installed at the end of the pipe. A light source 22 for exciting the pressure sensitive material and a light receiving element 26 (PMT (photomultiplier tube), model name: C6780, manufactured by Hamamatsu Photonics Co., Ltd.) are installed outside the test section 29. ing. Here, the response time is defined as the time required to reach 90% of the emission intensity based on the emission intensity after the step pressure change.

2.3. Test example 1 (characteristic evaluation test)
2.3.1. Pressure Sensitive Material and Solid Particle Dependence In Test Example 1, the above-described slurries (1) to (3) were used as the slurry. That is, the solid particles used were (1) SiO ₂ (average particle size 21 nm, 10% by mass), (2) Al ₂ O ₃ (average particle size 31 nm, 15% by mass), and (3) Al ₂ O _{3, respectively.} (Average particle diameter 700 nm, 15 mass%) (the same applies to FIGS. 4 and 5 described later).

FIG. 3 is a graph showing the relationship between the reciprocal of the relative light emission intensity (I / Iref) and the pressure when the light emission intensity (20 ° C.) of the pressure-sensitive material at atmospheric pressure is the reference value Iref (Stern-Volmer plot). It is. The pressure sensitivity of PSP can be evaluated based on the slope of this graph. In FIG. 3, solid lines ○, Δ, and □ indicate the case where a slurry using PtTFPP is used as a pressure-sensitive material, and shaded lines ○ and Δ indicate a slurry that uses Ru (dpp) ₃ as a pressure-sensitive material. The case where it is used is shown (the same applies to FIGS. 4 and 5 described later).

According to FIG. 3, it was found that the pressure sensitivity differs depending on the pressure sensitive material and the solid particles. It was also found that when PtTFPP was used as the pressure sensitive material, the pressure sensitivity was higher than when Ru (dpp) ₃ was used as the pressure sensitive material.

  FIG. 4 is a graph showing the relationship between light emission intensity and pressure of a pressure sensitive material at a predetermined temperature (20 ° C.). In FIG. 4, in order to eliminate the influence of the film thickness, the vertical axis is a value obtained by dividing the emission intensity by each measured film thickness value.

According to FIG. 4, when the pressure sensitive material is either PtTFPP or Ru (dpp) ₃ , when Al ₂ O ₃ is used as the solid particles, it is about twice as much as when SiO ₂ is used as the solid particles. It can be seen that the emission intensity of

  FIG. 5 is a graph (Arrhenius plot) showing the relationship between the relative light emission intensity of the pressure-sensitive material and the temperature at a predetermined pressure (100 kPa). FIG. 5 is a plot of relative light emission intensity (I / Iref) at each temperature, with the light emission intensity at 10 ° C. being a reference value Iref. The pressure was constant at 100 kPa.

According to FIG. 5, even when any slurry is used, a relatively large temperature sensitivity (1% / ° C.) is exhibited. In addition, the film formed from the slurry containing SiO ₂ as the solid particles has a substantially constant temperature sensitivity when either PtTFPP or Ru (dpp) ₃ is used as the pressure sensitive material, but the solid particles are made of Al. _The film formed from the slurry containing ₂ O ₃ had a difference in temperature sensitivity depending on the type of pressure sensitive material.

FIG. 6 shows the response characteristics of the pressure sensitive material to the step pressure increase. The film thickness of the sample used in FIG. 6 was unified to about 5 μm. According to FIG. 6, it can be seen that the difference in the solid particles has a great influence on the time response. That is, when (2) Al ₂ O ₃ (average particle size 31 nm) was used as the solid particles, the pressure did not become a constant value even after the pressure step, and the response time was 1 ms or more. On the other hand, when (1) SiO ₂ (average particle size 25 nm) is used as the solid particles, the response time when the pressure sensitive material is Ru (dpp) ₃ is 80 μs, and the pressure sensitive material is PtTFPP. In some cases, the response time was 40 μs, and it was confirmed to have high-speed response.

2.3.2. FIG. 7 is a graph showing changes in light emission intensity (under a constant temperature condition) with respect to changes in pressure when the film thickness is 2.5 μm, 5.1 μm, 11.5 μm, and 21.0 μm. It is. FIG. 8 is a graph showing the change in the reciprocal of the relative emission intensity with respect to the change in pressure when the film thickness is 2.5 μm, 5.1 μm, 11.5 μm, and 21.0 μm.

FIG. 7 shows the results of evaluation of a coating formed using a slurry containing PtTFPP (pressure sensitive material) and (1) SiO ₂ (average particle size 25 nm) (solid particles).

  According to FIG. 7, it can be seen that the emission intensity increases as the film thickness increases. As the cause, it is considered that the amount of the pressure sensitive material existing on the substrate increases as the film thickness of the coating increases.

  According to FIG. 7, the film thickness increases to 2.0 times, 4.6 times, and 8.4 times, whereas the emission intensity changes only 2 times, 3.6 times, and 5 times. Absent. That is, the emission intensity tends to increase as the film thickness increases, but no linear proportional relationship was found between the film thickness and the emission intensity. On the other hand, according to FIG. 8, the change in the reciprocal of the relative light emission intensity with respect to the change in pressure is constant irrespective of the film thickness of the coating.

From the above results, it is presumed that the pressure sensitivity does not depend on the film thickness and affects only the emission intensity. Although not shown, it was confirmed that the same tendency was observed when Ru (dpp) ₃ was used.

2.3.3. Discussion In Test Example 1, the difference in the crystal structure of the solid particles can be considered as one of the factors that caused the difference in emission intensity, pressure sensitivity, and time response depending on the type of solid particles. For example, SiO ₂ is typically because it has a sparse crystalline structure than _Al 2 _{O 3,} than if more of the case of using SiO ₂ as the solid particles used _Al 2 _{O 3,} the adsorption amount of the photosensitive material per unit volume Many are considered to have high oxygen permeability. Therefore, when using SiO ₂ as solid particles, believed to have excellent pressure sensitivity and time response than with Al ₂ O _3.

2.4. Test example 2 (demonstration test)
2.4.1. Experimental apparatus and method In this test example, in order to confirm whether the coating formed using the slurry of the present invention is adapted to unsteady pressure flow, the Japan Aerospace Exploration Agency, Japan Aerospace Exploration Agency (JAXA) / ISAS) A demonstration test was conducted in a 60 cm × 60 cm transonic wind tunnel owned by the company.

  FIG. 9 is a diagram schematically showing the configuration of the wind tunnel measuring apparatus used in the example of the present invention, and FIG. 10 is a diagram schematically showing a model 50 that is a target of wind tunnel measurement ((a)). Is a plan view, and (b) is a side view).

  A delta wing model 50 (see FIG. 10) was installed during the transonic speed to generate an unsteady aerodynamic phenomenon called a buffet. As shown in FIG. 10, PSP (pressure-sensitive paint) is applied to half of the model 50, TSP (temperature-sensitive paint) is applied to the other half, and PSP and TSP are measured simultaneously. The temperature sensitivity was corrected. Further, by providing the static pressure hole of the model 50 of FIG. 10, providing semiconductor pressure sensors 51 to 54 (model name: XCQ-062, manufactured by Kulite), and performing static pressure measurement with the sensors 51 to 54, The sensitivity of PSP was confirmed. In addition, the sensors 51-54 were each installed in the position shown by (1)-(4) of FIG.

  The ventilation test conditions were a Mach number of 0.9, a total pressure of 150 kPa, and an angle of attack of 20 °, the high-speed video camera 38 had a sampling frequency of 1 kHz and an exposure time of 998 μs, and data of the semiconductor pressure sensors 51 to 54 was acquired at 10 kHz. .

In this test example, a slurry containing a pressure-sensitive material (Ru (dpp) ₃ ), solid particles (SiO ₂ , average particle size: 25 nm, 10% by mass), an organic solvent (toluene), and a fatty acid (C18). Was used to form a coating on the model 50.

2.4.2. Experimental results When processing data obtained in a wind tunnel experiment, errors may occur due to the movement of the model due to aerodynamics and the temperature dependence of the PSP. To eliminate this error, the image processing program owned by Tokyo University of Agriculture and Technology Kameda Laboratory (Taro Magoshi, Hitoshi Seki, Masaharu Kameda, Kazuyuki Nakakita, “PSP measurement of transonic delta wing surface unsteady pressure”, No. 40 Proceedings of the annual hydrodynamics lecture (2008), pp. 369-372)).

  FIG. 11 is a diagram showing pressure field fluctuations on the blade surface of the model 50 measured in the wind tunnel in this test example at intervals of 2 ms (milliseconds) (FIG. 11 shows that the PSP of the model 50 was applied). Only the side wing surface is shown.) FIG. 11 shows how the separation vortex generated from the leading edge fluctuates due to a shock wave. Note that FIG. 11 is originally a color image and an image with a clearer data distribution state. However, since a color image cannot be shown in the patent specification, it is shown as a grayscale lightness gradation image. It is.

  FIG. 12 is a comparison between the semiconductor pressure sensors 51 to 54 and the time fluctuation values of the PSP data around the sensors. In FIG. 12, sensor (1) and sensor (4) indicate data measured by the pressure sensor 51 and sensor 54, respectively, and PSP (1) and PSP (4) indicate the pressure sensor 51 and pressure sensor 54, respectively. The data obtained by the surface pressure measurement by PSP in the vicinity are shown.

  In FIG. 12, it can be seen that a large amplitude of about 30 kPa of the sensor (1) is due to the influence of shock wave vibration. From this, it can be seen that the PSP captures the same fluctuation as the pressure sensors 51 to 54.

2.5. Conclusion As described above, according to the present invention, a slurry containing a pressure-sensitive material and solid particles is applied to the surface of an object to form a coating, and the surface pressure of the object is measured, thereby measuring the surface of the object. The pressure could be measured with high sensitivity by a simple method. In particular, it was found that a coating containing SiO ₂ as solid particles and PtTFPP as a pressure sensitive material has high pressure sensitivity and time response.

  This completes the description of the present embodiment. The present invention is not limited to the above-described embodiment, and various modifications can be made. Further, the invention includes substantially the same configuration (for example, a configuration having the same function, method, and result, or a configuration having the same purpose and result) as the configuration described in the embodiment. In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that exhibits the same operational effects as the configuration described in the embodiment or a configuration that can achieve the same object. Further, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

  The present invention can be used in a wide range of fields including measurement of surface pressure of transportation equipment (vehicles (automobiles, motorcycles, trains, etc.), aircrafts, ships, etc.).

It is a figure which shows typically the structure of the calibration test apparatus used in the Example of this invention. It is a figure which shows typically the structure of the shock tube used in the Example of this invention. It is a graph which shows the result (relationship of the reciprocal number of relative luminescence intensity, and a pressure) obtained by the pressure responsiveness test using the pressure-sensitive paint of one Example of this invention. It is a graph which shows the result (pressure dependence with respect to emitted light intensity) obtained by the pressure responsiveness test using the pressure-sensitive paint of one Example of this invention. It is a graph which shows the result (relationship between temperature and emitted light intensity) obtained by the temperature responsiveness test using the pressure-sensitive paint of one Example of this invention. It is a graph which shows the result (change with time of pressure) obtained by the time responsiveness test using the pressure sensitive paint of one example of the present invention. It is a graph which shows the result (relationship between a film thickness and light emission intensity) obtained by the pressure responsiveness test using the pressure-sensitive paint of one Example of this invention. It is a graph which shows the result (relationship between a film thickness and the reciprocal of a relative luminescence intensity) obtained by the pressure responsiveness test using the pressure sensitive paint of one Example of this invention. It is a figure which shows typically the structure of the wind tunnel measuring apparatus used in the Example of this invention. It is a figure which shows typically the model which is the object of the wind tunnel measurement of one Example of this invention ((a) shows a top view, (b) shows a side view). It is the figure which showed the pressure field fluctuation | variation on the wing | blade surface of the model which is the object of the wind tunnel measurement of one Example of this invention by 2 ms space | interval. It is a graph which shows a time-dependent change of the pressure measured by the semiconductor pressure sensor installed in the model shown in FIG. 10, and the pressure obtained by the pressure sensitive test in the said sensor vicinity.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10,40 ... Dark room, 11 ... Imaging device (CCD camera), 12, 22 ... Light source, 13 ... Chamber, 14 ... Sample, 15 ... Pressure control device, 16 ... Temperature control device, 17, 27 ... Computer (PC), DESCRIPTION OF SYMBOLS 19,39 ... Band pass filter, 20 ... Calibration test apparatus, 21 ... Diaphragm, 23 ... Valve, 24 ... High pressure chamber, 25 ... Low pressure chamber, 26 ... PMT, 28 ... Semiconductor pressure sensor, 29 ... Test section, 30 ... Shock wave Tube ... 31 ... flow, 33,50 ... model, 34 ... transmitted signal, 35 ... memory, 36 ... delay generator, 38 ... high speed video camera, 39 ... needle, 41 ... beam expander, 42 ... argon ion laser, 43 ... Plenum room, 51-54 ... Pressure sensor

Claims (10)

  A pressure-sensitive paint, which is a slurry containing a pressure-sensitive material and solid particles.   The pressure-sensitive paint according to claim 1, wherein the average particle diameter of the solid particles is 10 nm to 1 μm.   The pressure-sensitive paint according to claim 1 or 2, wherein the solid particles are at least one selected from silica, alumina, titanium oxide, ceria, magnesia, zinc oxide, and calcium carbonate.   The pressure-sensitive paint according to any one of claims 1 to 3, wherein the pressure-sensitive material is at least one selected from a porphyrin-based compound, a ruthenium complex, and an aromatic hydrocarbon. Forming a film on the surface of the object using the pressure-sensitive paint according to claim 1;
Measuring the surface pressure of the object including the coating;
A method for measuring the surface pressure of an object.   The method for measuring the surface pressure of an object according to claim 5, wherein the film has a thickness of 1 μm to 20 μm.   An object having a coating film including a pressure-sensitive material and solid particles having an average particle diameter of 10 nm to 1 μm.   The object according to claim 7, wherein the film has a thickness of 1 μm to 20 μm.   The object according to claim 7 or 8, wherein the solid particles are at least one selected from silica, alumina, titanium oxide, ceria, magnesia, zinc oxide, and calcium carbonate.   The object according to any one of claims 7 to 9, wherein the pressure-sensitive material is at least one selected from a porphyrin-based compound, a ruthenium complex, and an aromatic hydrocarbon.