Flow field visualization observation method and device based on infrared spectral absorption characteristics

Abstract

The present application relates to a method and device for visualizing and observing a flow field based on infrared spectral absorption characteristics, wherein the method includes: collecting temperature data of a high-temperature background solid wall based on the infrared spectral absorption characteristics of Freon; statistically analyzing the temperature distribution of the high-temperature background solid wall based on the temperature data, and analyzing the distribution of Freon based on the temperature distribution; obtaining the mixing state of Freon and air based on the distribution of Freon, and obtaining a visualized flow field of the Freon and air mixing process based on the mixing state, and performing a visualized display based on the visualized flow field. Thus, the problem that the addition of tracer particles in the related technology may affect the original flow state of the flow field, causing system errors, and the complexity of the experimental device and high experimental costs are solved.

Description

Technical Field

[0001] The present application relates to the technical field of fluid flow field observation and analysis, and particularly relates to a flow field visualization observation method and device based on infrared spectral absorption characteristics. Background Art

[0002] In the future, the turbine inlet temperature of aero-engines will be further increased. Improving the active thermal protection ability of materials and optimizing the active cooling design are of great significance for increasing the turbine inlet temperature and improving the engine performance. The main active cooling solutions are film cooling or transpiration cooling. Understanding the influence law of the geometric structure of hot-end components and the flow field parameters of the mainstream and secondary flows on the mixing heat transfer process of cold and hot airflows on the material surface is the necessary way to guide the active cooling thermal design. Understanding the law of the mixing process mainly relies on the flow field visualization method. It can be said that the flow field visualization observation is of great significance for understanding the airflow mixing process and the evolution law of the vortex system, and then guiding the design of film holes or transpiration pores and improving the cooling characteristics of hot-end components and the overall performance of the engine.

[0003] In the related art, the existing flow field visualization technology is mainly the particle image velocimetry (PIV). This technology injects tiny particles into the fluid. Since the geometric size and mass of the particles are too small, they move along with the fluid motion. Then, researchers can infer the change process of the flow field by observing the particle flow. The PIV technology has the significant advantages of high flow field display accuracy and obvious visualization effect.

[0004] However, the related art has the following several disadvantages: 1. The selection of tracer particles is very important. After all, the volume and weight of the tracer particles cannot be ignored. Adding tracer particles may affect the original flow state of the flow field and cause systematic errors; 2. The cost of this technology is too high. Generally, it is very difficult for scientific research institutions to configure PIV-related equipment and bear the high costs during the experiment. Summary of the Invention

[0005] The present application provides a flow field visualization observation method and device based on infrared spectral absorption characteristics to solve the problems in the related art that adding tracer particles may affect the original flow state of the flow field, cause systematic errors, the complexity of the experimental device and the experimental cost are relatively high, etc.

[0006] The first aspect of the embodiments of the present application provides a method for visualizing the flow field based on the infrared spectral absorption characteristics, including the following steps: collecting the temperature data of the high-temperature background solid wall based on the infrared spectral absorption characteristics of Freon; statistically analyzing the temperature distribution of the high-temperature background solid wall according to the temperature data, and analyzing the distribution of Freon according to the temperature distribution; obtaining the mixing state of Freon and air according to the distribution of Freon, obtaining the visualized flow field of the mixing process of Freon and air according to the mixing state, and performing visual display according to the visualized flow field.

[0007] Optionally, in an embodiment of the present application, the performing visual display according to the visualized flow field includes: controlling the high-temperature background solid wall to meet the preset temperature condition to obtain an infrared thermal imaging photo that meets the preset brightness and contrast conditions; adjusting the infrared light transmission band of the infrared thermal imager by using the filter light-transmitting film of the infrared thermal imager to obtain the adjusted detection band of the thermal imager; making the adjusted detection light-transmitting band of the thermal imager reach the target contrast of the visualized flow field, and performing visual display on the visualized flow field according to the infrared thermal imaging photo that meets the preset brightness and contrast conditions under the target contrast.

[0008] Optionally, in an embodiment of the present application, the calculation formula for the infrared spectral radiant power on the high-temperature background solid wall is:

[0009]

[0010] where c 1 and c 2 are related constants, λ is the infrared emission energy band of the high-temperature background solid wall, and T is the temperature of the high-temperature background solid wall;

[0011] The calculation formula for the energy of the high-temperature background solid wall in the infrared light transmission band is:

[0012]

[0013] where c 1 and c 2 are the related constants, λ is the infrared emission energy band of the high-temperature background solid wall, T is the temperature of the high-temperature background solid wall, and dλ is the differential of the wavelength;

[0014] The calculation formula for the infrared spectral radiant power in the adjusted detection band of the thermal imager is:

[0015]

[0016] where c 1 and c2 where \(C\) is the relevant constant, \(\lambda\) is the infrared emission energy band of the high-temperature background solid wall, \(T\) is the temperature of the high-temperature background solid wall, and \(d\lambda\) is the differential of the wavelength.

[0017] Optionally, in an embodiment of the present application, the visual display according to the visualized flow field further includes: processing the image data collected by the infrared thermal imager according to the shooting parameters of the infrared thermal imager, and reconstructing the image data to obtain a visualized flow field image that meets the preset clarity condition and preset resolution condition, and visually displaying the visualized flow field according to the visualized flow field image.

[0018] Optionally, in an embodiment of the present application, the step of statistically analyzing the temperature distribution of the high-temperature background solid wall according to the temperature data and analyzing the distribution of the refrigerant according to the temperature distribution includes: determining whether there is the air between the infrared thermal imager and the high-temperature background solid wall; if there is the air between the infrared thermal imager and the high-temperature background solid wall, obtaining the temperature distribution of the high-temperature background solid wall according to the infrared emissivity of the solid wall; if there is the refrigerant in the air, statistically analyzing the temperature distribution of the high-temperature background solid wall according to the temperature data, and analyzing the distribution of the refrigerant according to the temperature distribution.

[0019] An embodiment of the second aspect of the present application provides a flow field visualization observation device based on the infrared spectral absorption characteristics, including: a collection module, configured to collect temperature data of a high-temperature background solid wall based on the infrared spectral absorption characteristics of the refrigerant; an analysis module, configured to statistically analyze the temperature distribution of the high-temperature background solid wall according to the temperature data, and analyze the distribution of the refrigerant according to the temperature distribution; a visualization module, configured to obtain the mixing state of the refrigerant and the air according to the distribution of the refrigerant, obtain a visualized flow field of the mixing process of the refrigerant and the air according to the mixing state, and visually display the visualized flow field.

[0020] Optionally, in an embodiment of the present application, the visualization module includes: a control unit, configured to control the high-temperature background solid wall to meet a preset temperature condition to obtain an infrared thermal imaging photo that meets the preset brightness and contrast conditions; an adjustment unit, configured to adjust the infrared transmission band of the infrared thermal imager by using a filter light-transmitting film of the infrared thermal imager to obtain an adjusted detection band of the thermal imager; a first visualization unit, configured to make the adjusted detection light-transmitting band of the thermal imager reach the target contrast of the visualized flow field, and visually display the visualized flow field according to the infrared thermal imaging photo that meets the preset brightness and contrast conditions at the target contrast.

[0021] Optionally, in an embodiment of the present application, the calculation formula for the infrared spectral radiant power on the high-temperature background solid wall is as follows:

[0022]

[0023] Wherein, c 1 and c 2 are related constants, λ is the infrared emission energy band of the high-temperature background solid wall, and T is the temperature of the high-temperature background solid wall;

[0024] The calculation formula for the energy of the high-temperature background solid wall in the infrared transparent band is as follows:

[0025]

[0026] Wherein, c 1 and c 2 are the related constants, λ is the infrared emission energy band of the high-temperature background solid wall, T is the temperature of the high-temperature background solid wall, and dλ is the differential of the wavelength;

[0027] The calculation formula for the infrared spectral radiant power on the adjusted detection band of the thermal imager is as follows:

[0028]

[0029] Wherein, c 1 and c 2 are the related constants, λ is the infrared emission energy band of the high-temperature background solid wall, T is the temperature of the high-temperature background solid wall, and dλ is the differential of the wavelength.

[0030] Optionally, in an embodiment of the present application, the visualization module further includes: a second visualization unit, configured to process the image data collected by the infrared thermal imager according to the shooting parameters of the infrared thermal imager, reconstruct the image data, obtain a visualized flow field image that meets the preset clarity condition and preset resolution condition, and perform visual display on the visualized flow field according to the visualized flow field image.

[0031] Optionally, in an embodiment of the present application, the analysis module includes: a judgment unit configured to judge whether there is the air between the infrared thermal imager and the high-temperature background solid wall; an acquisition unit configured to obtain the temperature distribution of the high-temperature background solid wall according to the infrared emissivity of the solid wall when there is the air between the infrared thermal imager and the high-temperature background solid wall; and an analysis unit configured to, when there is the Freon in the air, count the temperature distribution of the high-temperature background solid wall according to the temperature data and analyze the distribution of the Freon according to the temperature distribution.

[0032] The third aspect embodiment of the present application provides an electronic device, including: a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor executes the program to implement the flow field visualization observation method based on the infrared spectral absorption characteristics as described in the above embodiment.

[0033] The fourth aspect embodiment of the present application provides a computer-readable storage medium storing a computer program, and when the program is executed by a processor, it implements the flow field visualization observation method based on the infrared spectral absorption characteristics as above.

[0034] The fifth aspect embodiment of the present application provides a computer program product storing a computer program, and when the program is executed by a processor, it implements the flow field visualization observation method based on the infrared spectral absorption characteristics as above.

[0035] The embodiment of the present application may use Freon as the blending fluid, obtain the visualization flow field of the Freon and air blending process according to the blending state, and by increasing the temperature of the high-temperature background solid wall and installing a filtering and light-transmitting film to improve the contrast of the visualization flow field, while ensuring the accuracy and resolution of the flow field visualization, the cost is low and the operation is simple, without adding other light sources or tracer particles. Thereby, the problems in the related art that adding tracer particles may affect the original flow state of the flow field, causing systematic errors, and the complexity of the experimental device and the experimental cost are relatively high are solved.

[0036] The additional aspects and advantages of the present application will be partly given in the following description, partly will become obvious from the following description, or will be understood through the practice of the present application. Description of the Drawings

[0037] The above and / or additional aspects and advantages of the present application will become obvious and easy to understand from the following description of the embodiments in conjunction with the drawings, where:

[0038] Figure 1 It is a flowchart of a flow field visualization observation method based on the infrared spectral absorption characteristics according to an embodiment of the present application;

[0039] Figure 2 Schematic diagram of the principle of the flow field visualization observation method based on infrared spectral absorption characteristics according to an embodiment of the present application;

[0040] Figure 3 Graph showing the relationship between the infrared spectral emissive power and wavelength of the flow field visualization observation method based on infrared spectral absorption characteristics according to an embodiment of the present application;

[0041] Figure 4 Graph showing the relationship between the absorption proportionality coefficient and temperature at different temperatures of the flow field visualization observation method based on infrared spectral absorption characteristics according to an embodiment of the present application;

[0042] Figure 5 Schematic diagram of the structure of a flow field visualization observation device based on infrared spectral absorption characteristics provided according to an embodiment of the present application;

[0043] Figure 6 Schematic diagram of the structure of an electronic device provided according to an embodiment of the present application. Detailed implementation manners

[0044] The embodiments of the present application will be described in detail below. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present application, and should not be construed as limiting the present application.

[0045] The flow field visualization observation method and device based on infrared spectral absorption characteristics according to an embodiment of the present application will be described below with reference to the accompanying drawings. In view of the problems in the related art mentioned in the above background technology that adding tracer particles may affect the original flow state of the flow field, causing systematic errors, and the complexity and experimental cost of the experimental device are relatively high, the present application provides a flow field visualization observation method based on infrared spectral absorption characteristics. In this method, Freon can be used as the mixing fluid, and the visualization flow field of the mixing process of Freon and air can be obtained according to the mixing state. By increasing the temperature of the high-temperature background solid wall and installing a filtering light-transmitting film, the contrast of the visualization flow field is improved, and the cost is low and the operation is simple without adding other light sources or tracer particles while ensuring the visualization accuracy and resolution of the flow field. Thus, the problems in the related art that adding tracer particles may affect the original flow state of the flow field, causing systematic errors, and the complexity and experimental cost of the experimental device are relatively high are solved.

[0046] Specifically, Figure 1 Schematic flow chart of a flow field visualization observation method based on infrared spectral absorption characteristics provided according to an embodiment of the present application.

[0047] As shown in Figure 1 the following steps are included in the flow field visualization observation method based on the infrared spectral absorption characteristics:

[0048] In step S101, based on the infrared spectral absorption characteristics of Freon, the temperature data of the high-temperature background solid wall is collected.

[0049] It can be understood that in the embodiments of the present application, gaseous Freon (such as R134a, etc.) is used as the secondary flow cooling medium, and the mainstream hot fluid is hot air.

[0050] In the actual implementation process, the gaseous Freon R134a in the embodiments of the present application has a strong absorption peak in the infrared band of 8 - 8.5 microns. During the process of infrared light passing through the Freon gas, a large amount of its infrared energy will be absorbed, while in this band, air is in a state of complete transmission for the energy of infrared light, and the infrared light energy can completely pass through the air. In the embodiments of the present application, based on the infrared spectral absorption characteristics of Freon, an infrared thermal imager can be used to photograph and collect the temperature of the high-temperature background solid wall, and the temperature data of the high-temperature background solid wall can be obtained.

[0051] In the embodiments of the present application, Freon can be used as the mixing fluid (or mixing tracer fluid), combined with an infrared thermal imager for flow field observation, and the infrared absorption characteristics of Freon can be utilized for flow field visualization observation, so as to reduce the complexity of the experimental device and the experimental cost while ensuring the visualization accuracy and resolution of the flow field.

[0052] In step S102, according to the temperature data, the temperature distribution of the high-temperature background solid wall is statistically analyzed, and the distribution of Freon is analyzed according to the temperature distribution.

[0053] As a possible implementation manner, in the embodiments of the present application, the temperature distribution of the high-temperature background solid wall can be statistically analyzed according to the temperature data of the high-temperature background solid wall, and the distribution of Freon can be reflected according to the temperature distribution. Among them, the distribution of Freon is reflected as the projection of the position where the Freon gas is located on the photographed wall.

[0054] In the embodiments of the present application, the temperature distribution of the high-temperature background solid wall can be statistically analyzed to reflect the distribution of Freon, providing support for obtaining the visualized flow field of the mixing process of Freon and air subsequently.

[0055] Optionally, in an embodiment of the present application, the temperature distribution of the high-temperature background solid wall is statistically analyzed based on the temperature data, and the distribution of Freon is analyzed based on the temperature distribution, including: determining whether there is air between the infrared thermal imager and the high-temperature background solid wall; if there is air between the infrared thermal imager and the high-temperature background solid wall, the temperature distribution of the high-temperature background solid wall is obtained based on the infrared emissivity of the solid wall; if there is Freon in the air, the temperature distribution of the high-temperature background solid wall is statistically analyzed based on the temperature data, and the distribution of Freon is analyzed based on the temperature distribution.

[0056] It can be understood that the infrared thermal imager in the embodiment of the present application calculates the temperature by sensing the radiation energy. If the radiation energy decreases due to the absorption of Freon, the radiation energy sensed by the thermal imager will decrease, resulting in a lower temperature measurement.

[0057] In the actual execution process, the embodiment of the present application can determine whether there is completely air between the infrared thermal imager and the high-temperature background solid wall. If there is only air between the infrared thermal imager and the high-temperature background solid wall, after correctly setting the infrared emissivity of the solid wall, the temperature field distribution of the wall can be accurately obtained. If there is also Freon fluid in the air, when photographing the same high-temperature background plate at the same temperature, the temperature distribution will change. The infrared absorption characteristics of Freon will cause the temperature of the photographed wall to decrease. The temperature distribution of the high-temperature background solid wall can be statistically analyzed based on the temperature data, and the distribution of Freon can be analyzed based on the temperature distribution.

[0058] In step S103, the mixing state of Freon and air is obtained based on the distribution of Freon, the visualized flow field of the mixing process of Freon and air is obtained based on the mixing state, and the visualized flow field is visually displayed.

[0059] In the actual execution process, the embodiment of the present application can obtain the mixing state of Freon and air based on the distribution of Freon, and finally obtain the visualized flow field of the mixing process of Freon and air based on the mixing state, and visually display the visualized flow field to improve and enhance the visualization effect. Among them, the parameters for improving the visualization observation effect include the flow field observation contrast, clarity, and resolution.

[0060] The embodiment of the present application can be used for the research on the visualization problem of the mixing flow field of the mainstream and secondary flows in the film cooling and transpiration active cooling processes of the hot-end components of aeroengines. While ensuring the visualization accuracy and resolution of the flow field, the complexity of the experimental device and the experimental cost are greatly reduced.

[0061] Optionally, in an embodiment of the present application, visual display is performed according to the visualized flow field, including: controlling the high-temperature background solid wall to meet the preset temperature condition to obtain an infrared thermal imaging photo that meets the preset brightness and contrast conditions; using the filtering light-transmitting film of the infrared thermal imager to adjust the infrared light-transmitting band of the infrared thermal imager to obtain the adjusted detection band of the thermal imager; making the adjusted detection light-transmitting band of the thermal imager reach the target contrast of the visualized flow field, and at the target contrast, visualizing the visualized flow field according to the infrared thermal imaging photo that meets the preset brightness and contrast conditions.

[0062] Among them, the preset temperature condition in the embodiment of the present application can be the condition of raising the temperature of the high-temperature background solid wall to meet the requirements; the preset brightness and contrast conditions can be the conditions of raising the brightness and contrast of the infrared thermal imaging photo to meet the requirements.

[0063] It can be understood that the embodiment of the present application relies on the temperature change of the solid background to obtain the distribution of the Freon fluid, and then obtains the flow field visualization result. Therefore, maximizing the solid background temperature is the key to improving the brightness and contrast of the infrared photo, because the infrared photo is brighter where there is only air and darker where there is Freon, and the greater the Freon concentration, the darker the photo.

[0064] However, unrestricted increase in the background temperature will also cause negative effects. For example, if the background comes into contact with the mainstream hot air, the temperature of the mainstream flowing gas will rise due to the high temperature of the background solid, which will seriously affect the flow field, and the effect of unrestricted increase in temperature on improving the contrast is limited. Therefore, in the actual implementation process, in order to achieve the purpose of increasing the background temperature while ensuring that the background solid wall does not affect the flow field temperature distribution of the mainstream hot air, the embodiment of the present application can be based on the infrared glass window provided between the high-temperature background solid wall and the hot fluid pipeline, and photograph the background solid through the high-transmission infrared glass to prevent the wall temperature from affecting the temperature of the mainstream hot air, as Figure 2 shown. The embodiment of the present application can control the high-temperature background solid wall to meet certain temperature conditions through schemes such as electric heating to improve the brightness and contrast of the infrared photo, and obtain an infrared thermal imaging photo that meets the contrast requirements of the visualized flow field.

[0065] Furthermore, the embodiment of the present application can use the filtering light-transmitting film of the infrared thermal imager to adjust the light-transmitting band of the infrared thermal imager, change the lens light-transmitting band of the thermal imager from 7-14 microns to 7.5-9 microns (slightly larger than the Freon absorption peak), obtain the adjusted light-transmitting band, improve the target contrast of the visualized flow field according to the adjusted light-transmitting band, and at the target contrast, visualize the visualized flow field according to the infrared thermal imaging photo with improved brightness and contrast, ensuring a better flow field visualization result through the improved contrast effect.

[0066] Specifically, the light transmission band of the infrared thermal imager lens is 7-14 microns, while the absorption peak band of Freon is 8-8.5 microns. The light transmission band of the thermal imager lens must completely cover the absorption band of Freon. However, if the thermal imager band is much larger than the Freon absorption band, the total proportion of the energy absorbed by Freon in the energy received by the thermal imager will decrease (i.e., the proportion of the infrared energy absorbed due to the presence of Freon in the total infrared emission energy decreases), resulting in a reduction in the contrast of the imaging result. Therefore, the best way to improve the contrast is to change the light transmission band of the thermal imager lens from 7-14 microns to 7.5-9 microns (slightly larger than the Freon absorption peak), which can significantly improve the imaging contrast (in the 7.5-9 micron band, the infrared emission energy of the high-temperature wall surface due to the presence of Freon is basically absorbed, and the observed temperature will be very low). The purpose of changing the thermal imager receiving band can be achieved by installing a filtering light-transmitting film with a specific band of 7.5-9 microns in front of the lens.

[0067] The embodiment of the present application can increase the background wall surface temperature to enhance the shooting contrast, and use a 7.5-9 micron filtering light-transmitting film coating to enhance the flow field shooting contrast, with low cost, simple operation, and no need to add other light sources or tracer particles.

[0068] It should be noted that the preset temperature conditions, preset brightness and contrast conditions can be set by those skilled in the art according to the actual situation, and no specific limitations are made here.

[0069] Optionally, in an embodiment of the present application, the calculation formula for the infrared spectral radiant power of the high-temperature background solid wall surface is:

[0070]

[0071] Where c 1 and c 2 are related constants, λ is the infrared emission energy band of the high-temperature background solid wall surface, and T is the temperature of the high-temperature background solid wall surface;

[0072] The calculation formula for the energy of the high-temperature background solid wall surface in the infrared light transmission band is:

[0073]

[0074] Where c 1 and c 2 are related constants, λ is the infrared emission energy band of the high-temperature background solid wall surface, T is the temperature of the high-temperature background solid wall surface, and dλ is the differential of the wavelength;

[0075] The calculation formula for the infrared spectral radiant power in the adjusted thermal imager detection band is:

[0076]

[0077] Among them, c 1 and c 2 are related constants, λ is the infrared emission energy band of the high-temperature background solid wall, T is the temperature of the high-temperature background solid wall, and dλ is the differential of the wavelength.

[0078] It can be understood that the infrared spectral radiant intensity E bλ (unit: W / m2μm) is defined as the radiant energy per unit wavelength under given temperature conditions. The integral of the spectral radiant intensity with respect to the wavelength is the total energy of the object's infrared emission.

[0079] Specifically, the calculation formula for the infrared spectral radiant intensity is:

[0080]

[0081] c 1 = 3.7419×10 8 Wμm 4 / m 2 ,

[0082] c 2 = 1.439×10 4 μmK,

[0083] Generally, the detection band of uncooled long-wave infrared thermal imagers is between 7 - 14 microns. Therefore, the energy (E b1 ) of the detected object in this band can be calculated by the following formula, and its energy is the area enclosed by the radiation force curve and the x-axis. As Figure 3 shown, appropriately increasing the background wall temperature T helps to increase the spectral emissivity and thus increase the brightness of the visual imaging. However, the final imaging effect is also related to the contrast.

[0084]

[0085] The absorption band of Freon R134a is located at 8 - 8.5μm. In this band, if the gas between the detected wall and the thermal imager is 100% Freon R134a, then the infrared energy radiated by the wall in the 8 - 8.5μm band is almost completely absorbed by Freon, and the thermal imager cannot detect it. This part of the energy is defined as E b2 :

[0086]

[0087] Because the presence of Freon R134a causes energy absorption, the absorption ratio α can be defined as: α = E b2 / E b1 , and the larger this proportional coefficient, the more obvious the contrast of the infrared visual imaging and the better the imaging effect.Figure 4 It is the relationship between the coefficient α and the temperature under different wall temperature conditions without adding a filtering light-transmitting film. Among them, the higher the temperature, the greater the absorption coefficient, but the cost of increasing the temperature is also higher. Generally, after 600K, the increasing trend of the absorption coefficient with the increase of temperature weakens. Therefore, considering the background brightness, the absorption coefficient, and the cost of increasing the temperature comprehensively, 600K can be adopted as a reasonable background wall temperature.

[0088] In addition, after treatment with a filtering light-transmitting film (installing a filtering light-transmitting film with a wavelength range of 8 - 8.5 μm, which is exactly the same as the absorption band of R134a, on the infrared lens), the absorption coefficient can be further increased to nearly 100%.

[0089] Optionally, in an embodiment of the present application, for visual display according to the visualized flow field, it further includes: processing the image data collected by the infrared thermal imager according to the shooting parameters of the infrared thermal imager, and reconstructing the image data to obtain a visualized flow field image that meets the preset clarity condition and preset resolution condition, and performing visual display on the visualized flow field according to the visualized flow field image.

[0090] It can be understood that the visualized flow field image that meets the preset clarity condition and preset resolution condition in the embodiment of the present application can be a flow field photo with higher clarity and resolution.

[0091] In the actual execution process, the most direct means to improve the clarity in the embodiment of the present application is to use an infrared thermal imager with a higher pixel. Currently, the physical actual resolution of the infrared thermal imager can reach 1024*768. It can be considered to take multiple groups of photos of the same flow field at various angles along the same flow field during shooting, that is, to take photos of the same flow field at different positions and angles, so as to process the image data collected by the infrared thermal imager according to the shooting parameters of the infrared thermal imager, and use methods such as artificial intelligence to reconstruct the obtained large number of photos at different angles and positions to obtain a flow field photo that meets higher clarity and resolution. In addition, a scheme of increasing the concentration of Freon can also be adopted to make the fluid mixing boundary in the diffusion process clearer.

[0092] The embodiment of the present application can perform visual display on the visualized flow field, improve the visualization effect of the visualized flow field, and improve the clarity and resolution of the visualized flow field.

[0093] It should be noted that the preset clarity condition and preset resolution condition can be set by those skilled in the art according to the actual situation, and no specific limitation is made here.

[0094] According to the flow field visualization observation method based on the infrared spectral absorption characteristics proposed in the embodiments of the present application, Freon can be used as the mixing fluid, and the visualized flow field of the mixing process of Freon and air can be obtained according to the mixing state. By raising the temperature of the high-temperature background solid wall and installing a filter transparent film to improve the contrast of the visualized flow field, while ensuring the visualization accuracy and resolution of the flow field, the cost is low and the operation is simple, without adding other light sources or tracer particles. Thus, the problems in the related art that adding tracer particles may affect the original flow state of the flow field, causing systematic errors, and the complexity of the experimental device and the experimental cost are relatively high are solved.

[0095] Next, a flow field visualization observation device based on the infrared spectral absorption characteristics proposed in the embodiments of the present application will be described with reference to the accompanying drawings.

[0096] Figure 5 FIG. is a schematic structural diagram of a flow field visualization observation device based on the infrared spectral absorption characteristics according to an embodiment of the present application.

[0097] As Figure 5 shown, the flow field visualization observation device 10 based on the infrared spectral absorption characteristics includes: a collection module 100, an analysis module 200, and a visualization module 300.

[0098] Specifically, the collection module 100 is used to collect the temperature data of the high-temperature background solid wall based on the infrared spectral absorption characteristics of Freon.

[0099] The analysis module 200 is used to statistically analyze the temperature distribution of the high-temperature background solid wall according to the temperature data, and analyze the distribution of Freon according to the temperature distribution.

[0100] The visualization module 300 is used to obtain the mixing state of Freon and air according to the distribution of Freon, obtain the visualized flow field of the mixing process of Freon and air according to the mixing state, and perform visual display according to the visualized flow field.

[0101] Optionally, in an embodiment of the present application, the visualization module 300 includes: a control unit, an adjustment unit, and a first visualization unit.

[0102] Among them, the control unit is used to control the high-temperature background solid wall to meet the preset temperature conditions, and obtain an infrared thermal imaging photo that meets the preset brightness and contrast conditions.

[0103] The adjustment unit is used to adjust the infrared light transmission band of the infrared thermal imager by using the filter transparent film of the infrared thermal imager to obtain the adjusted light transmission band detected by the thermal imager.

[0104] The first visualization unit is configured to make the detection light transmission band of the adjusted thermal imager reach the target contrast of the visual flow field, and visualize the visual flow field according to the infrared thermal imaging photo that meets the preset brightness and contrast conditions at the target contrast.

[0105] Optionally, in an embodiment of the present application, the calculation formula for the infrared spectral radiant power on the high-temperature background solid wall surface is:

[0106]

[0107] where c 1 and c 2 are related constants, λ is the infrared emission energy band of the high-temperature background solid wall surface, and T is the temperature of the high-temperature background solid wall surface;

[0108] The calculation formula for the energy of the high-temperature background solid wall surface in the infrared light transmission band is:

[0109]

[0110] where c 1 and c 2 are related constants, λ is the infrared emission energy band of the high-temperature background solid wall surface, T is the temperature of the high-temperature background solid wall surface, and dλ is the differential of the wavelength;

[0111] The calculation formula for the infrared spectral radiant power in the detection band of the adjusted thermal imager is:

[0112]

[0113] where c 1 and c 2 are related constants, λ is the infrared emission energy band of the high-temperature background solid wall surface, T is the temperature of the high-temperature background solid wall surface, and dλ is the differential of the wavelength.

[0114] Optionally, in an embodiment of the present application, the visualization module 300 further includes: a second visualization unit.

[0115] where the second visualization unit is configured to process the image data collected by the infrared thermal imager according to the shooting parameters of the infrared thermal imager, reconstruct the image data to obtain a visual flow field image that meets the preset clarity condition and preset resolution condition, and visualize the visual flow field according to the visual flow field image.

[0116] Optionally, in an embodiment of the present application, the analysis module 200 includes: a judgment unit, an acquisition unit, and an analysis unit.

[0117] Among them, a judgment unit is configured to judge whether there is air between the infrared thermal imager and the high-temperature background solid wall surface.

[0118] An acquisition unit is configured to, when there is air between the infrared thermal imager and the high-temperature background solid wall surface, obtain the temperature distribution of the high-temperature background solid wall surface according to the infrared emissivity of the solid wall surface.

[0119] An analysis unit is configured to, when there is Freon in the air, statistically analyze the temperature distribution of the high-temperature background solid wall surface according to the temperature data, and analyze the distribution of Freon according to the temperature distribution.

[0120] It should be noted that the foregoing explanation of the embodiment of the flow field visualization observation method based on the infrared spectral absorption characteristics also applies to the flow field visualization observation device based on the infrared spectral absorption characteristics of this embodiment, and will not be elaborated here.

[0121] According to the flow field visualization observation device based on the infrared spectral absorption characteristics provided by the embodiments of the present application, Freon can be used as the mixing fluid, and the visual flow field of the mixing process of Freon and air can be obtained according to the mixing state. By increasing the temperature of the high-temperature background solid wall surface and installing a filter light-transmitting film, the contrast of the visual flow field can be improved, and the cost is low and the operation is simple without adding other light sources or tracer particles while ensuring the flow field visualization accuracy and resolution. Thus, the problems in the related art that adding tracer particles may affect the original flow state of the flow field, causing systematic errors, and the complexity of the experimental device and the experimental cost are relatively high are solved.

[0122] Figure 6 The following is a schematic structural diagram of an electronic device provided by an embodiment of the present application. The electronic device may include:

[0123] A memory 601, a processor 602, and a computer program stored on the memory 601 and executable on the processor 602.

[0124] When the processor 602 executes the program, it implements the flow field visualization observation method based on the infrared spectral absorption characteristics provided in the foregoing embodiment.

[0125] Further, the electronic device further includes:

[0126] A communication interface 603 for communication between the memory 601 and the processor 602.

[0127] The memory 601 is used to store a computer program executable on the processor 602.

[0128] The memory 601 may include a high-speed RAM memory, and may also include non-volatile memory, such as at least one disk memory.

[0129] If the memory 601, the processor 602, and the communication interface 603 are implemented independently, the communication interface 603, the memory 601, and the processor 602 can be interconnected through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of simplicity in representation, Figure 6 only a thick line is used in the figure, but it does not mean that there is only one bus or one type of bus.

[0130] Optionally, in a specific implementation, if the memory 601, the processor 602, and the communication interface 603 are integrated on a single chip, the memory 601, the processor 602, and the communication interface 603 can communicate with each other through an internal interface.

[0131] The processor 602 may be a Central Processing Unit (CPU), or an Application Specific Integrated Circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0132] This embodiment also provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, the above method for visual observation of a flow field based on infrared spectral absorption characteristics is implemented.

[0133] The embodiments of the present application also provide a computer program product, on which a computer program is stored. When the program is executed by a processor, the above method for visual observation of a flow field based on infrared spectral absorption characteristics is implemented.

[0134] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc., mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0135] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of this application, the meaning of "N" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0136] Any process or method description shown in a flowchart or described in other ways herein can be understood to represent a module, segment, or portion of code including one or N executable instructions for implementing a customized logical function or process, and the scope of the preferred embodiments of this application includes additional implementations, where the functions can be executed in a manner that is not in the order shown or discussed, including in a substantially simultaneous manner according to the functions involved or in a reverse order, which should be understood by those skilled in the art to which the embodiments of this application pertain.

[0137] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definable sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch instructions from the instruction execution system, apparatus, or device and execute the instructions), or used in combination with these instruction execution systems, apparatus, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transmit a program for use by or in combination with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection portion (electronic device) having one or N wirings, a portable computer disk cartridge (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically by optically scanning the paper or other media, followed by editing, interpretation, or otherwise processing as appropriate, and then storing it in a computer memory.

[0138] It should be understood that various parts of the present application can be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, the N steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application-specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0139] Those of ordinary skill in the art of the present technology can understand that all or part of the steps carried by the method of implementing the above embodiments can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0140] In addition, each functional unit in various embodiments of the present application may be integrated into one processing module, or each unit may exist physically alone, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0141] The above-mentioned storage medium may be a read-only memory, a magnetic disk, an optical disc, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A flow field visualization observation method based on infrared spectrum absorption characteristics, characterized in that: The following steps are involved: Based on the infrared spectrum absorption characteristics of Freon, the temperature data of the high-temperature background solid wall is collected; The temperature distribution of the high-temperature background solid wall is calculated based on the temperature data, and the distribution of the Freon is analyzed based on the temperature distribution, wherein the temperature distribution of the high-temperature background solid wall is calculated based on the temperature data, and the distribution of the Freon is analyzed based on the temperature distribution, including: judging whether there is air between the infrared thermal imager and the high-temperature background solid wall; if there is air between the infrared thermal imager and the high-temperature background solid wall, obtaining the temperature distribution of the high-temperature background solid wall based on the infrared emissivity of the high-temperature background solid wall; if there is Freon in the air, calculating the temperature distribution of the high-temperature background solid wall based on the temperature data, and analyzing the distribution of the Freon based on the temperature distribution; The mixing state of the Freon and the air is obtained according to the distribution of the Freon, and the visualized flow field of the mixing process of the Freon and the air is obtained according to the mixing state, and a visual display is performed according to the visualized flow field, wherein the visual display according to the visualized flow field includes: controlling the high-temperature background solid wall to meet the preset temperature condition, and obtaining an infrared thermal imaging photo that meets the preset brightness and contrast conditions; adjusting the infrared light transmission band of the infrared thermal imager by using the filter transparent film of the infrared thermal imager to obtain the infrared thermal imager detection light transmission band; making the infrared thermal imager detection light transmission band reach the target contrast of the visualized flow field, and under the target contrast, the visualized flow field is visualized according to the infrared thermal imaging photo that meets the preset brightness and contrast conditions.

2. The method according to claim 1, characterized in that: The calculation formula of the infrared spectrum radiation force on the high temperature background solid wall is: Wherein, c1 and c2 are related constants, λ is the infrared emission energy band of the high temperature background solid wall, and T is the temperature of the high temperature background solid wall; The energy calculation formula of the high temperature background solid wall in the 7-14 micron infrared transmission band is: Wherein, c1 and c2 are the related constants, λ is the infrared emission energy band of the high temperature background solid wall, T is the temperature of the high temperature background solid wall, and dλ is the differential of the wavelength; The calculation formula of the energy detected by the infrared thermal imager in the light transmission band is: Among them, c1 and c2 are the related constants, λ is the infrared emission energy band of the high-temperature background solid wall, T is the temperature of the high-temperature background solid wall, and dλ is the differential of the wavelength.

3. The method according to claim 1, characterized in that The visual display according to the visual flow field further includes: The image data collected by the infrared thermal imager is processed according to the shooting parameters of the infrared thermal imager, and the image data is reconstructed to obtain a visualized flow field image that meets preset clarity conditions and preset resolution conditions, and the visualized flow field is visualized based on the visualized flow field image.

4. A flow field visualization observation device based on infrared spectrum absorption characteristics, characterized in that: include: The acquisition module is used to collect temperature data of the high-temperature background solid wall based on the infrared spectrum absorption characteristics of Freon; An analysis module, used for counting the temperature distribution of the high-temperature background solid wall according to the temperature data, and analyzing the distribution of the Freon according to the temperature distribution, wherein the analysis module comprises: a judgment unit, used for judging whether there is air between the infrared thermal imager and the high-temperature background solid wall; an acquisition unit, used for obtaining the temperature distribution of the high-temperature background solid wall according to the infrared emissivity of the high-temperature background solid wall when the air exists between the infrared thermal imager and the high-temperature background solid wall; an analysis unit, used for counting the temperature distribution of the high-temperature background solid wall according to the temperature data when the Freon exists in the air, and analyzing the distribution of the Freon according to the temperature distribution; A visualization module is used to obtain the mixing state of the Freon and the air according to the distribution of the Freon, and to obtain a visualized flow field of the mixing process of the Freon and the air according to the mixing state, and to perform a visualization display according to the visualized flow field, wherein the visualization module includes: a control unit, used to control the high-temperature background solid wall to meet a preset temperature condition, and to obtain an infrared thermal imaging photo that meets preset brightness and contrast conditions; an adjustment unit, used to adjust the infrared light transmission band of the infrared thermal imager using a filter transparent film of the infrared thermal imager, and to obtain a detection light transmission band of the infrared thermal imager; a visualization unit, used to make the detection light transmission band of the infrared thermal imager reach a target contrast of the visualized flow field, and under the target contrast, the visualized flow field is visualized according to the infrared thermal imaging photo that meets the preset brightness and contrast conditions.

5. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the flow field visualization observation method based on infrared spectral absorption characteristics as described in any one of claims 1 to 3.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the flow field visualization observation method based on infrared spectrum absorption characteristics as described in any one of claims 1 to 3.

7. A computer program product, comprising a computer program, characterized in that The computer program is executed to implement the flow field visualization observation method based on infrared spectrum absorption characteristics as described in any one of claims 1 to 3.

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