A dynamic thermal camouflage system applicable to complex uncontrolled environments

Abstract

A dynamic thermal camouflage system suitable for use in a complex uncontrolled environment belongs to the field of dynamic thermal camouflage technology. In order to solve the problem of real-time control of the temperature field of a dynamic target in a complex uncontrolled environment and realize dynamic thermal camouflage under complex and changeable uncontrolled meteorological conditions, the present invention provides a dynamic thermal camouflage system suitable for use in a complex uncontrolled environment. The film uses liquid temperature change technology and fluid control to automatically control the surface temperature of the film, change the thermal radiation energy of equipment and personnel, and realize cross-regional adaptive thermal stealth or false display effects in a dynamic environment. The system includes a film, a thermal camouflage response system, and a thermal infrared characteristic analysis system. The present invention is applied to the influence of solar radiation, wind, rain, and fog on the surface temperature field of the camouflaged object to perform stealth or false display in the thermal infrared band. It can form a thermal camouflage film that can accurately control the thermal radiation energy of the camouflaged object in real time in a complex uncontrolled environment, and comprehensively improve the dynamic camouflage performance.

Description

Technical Field

[0001] The present invention belongs to the technical field of dynamic thermal camouflage, and particularly relates to a dynamic thermal camouflage system applicable to complex uncontrolled environments. Background Art

[0002] Dynamic thermal camouflage technology combines various technical means such as metamaterials, image processing, and dynamic control, dynamically adjusts the infrared radiation energy of the camouflaged object, adapts to the changes in environmental conditions, and ensures that the infrared radiation characteristics of the camouflaged object are always consistent or similar to those of the background, without being detected by reconnaissance. The variable temperature camouflage technology can not only hide the thermal characteristics of the camouflaged object through dynamic temperature change, but also distort the thermal characteristics of the camouflaged object to achieve the infrared decoy effect. Currently, the variable temperature technologies that have been studied more include phase change thermal control, electrochromic temperature change, and liquid temperature change. However, in the face of complex and changeable uncontrolled meteorological conditions, such as wind, rain, fog, and solar irradiation, the phase change thermal control and electrochromic temperature change technologies have limitations in dynamic camouflage, such as poor controllability of dynamic temperature regulation, insufficient sensitivity, and small temperature regulation range under the rapid change conditions of cross-regional, multi-season, and all-weather background environments. The liquid temperature change technology and fluid control have the characteristics of sensitive temperature response, strong controllability, and high energy efficiency, and the liquid has a wide adjustable temperature range and fast heat transfer speed. By changing the temperature, flow direction, and flow rate of the liquid, the rapid temperature change of the camouflaged object and the adaptation to various temperature distributions of the background can be achieved to meet the development needs of the new dynamic thermal camouflage technology.

[0003] The particularity of the complex uncontrolled environment directly affects the heat and mass transfer process on the surface of the camouflaged object, making the thermal infrared characteristics of the camouflaged object show more complex dynamic changes in complex environments such as rain and wind, fog, and direct sunlight. To seek a solution to the problem of real-time control of the temperature field of dynamic targets in complex uncontrolled environments, there is a lack of a thermal infrared characteristic analysis and response system applicable to complex meteorology, multi-factor interaction, and non-linear characteristic environments for accurate prediction and real-time response of the temperature field on the surface of the thermal camouflage flexible film, which is the key to accurately regulating the infrared radiation energy of the camouflaged object. Summary of the Invention

[0004] To solve the problem of real-time control of the temperature field of dynamic targets in complex uncontrolled environments and achieve dynamic thermal camouflage under complex and changeable uncontrolled meteorological conditions, the present invention provides a dynamic thermal camouflage system applicable to complex uncontrolled environments. This film uses liquid temperature change technology and fluid control to automatically regulate the temperature on the film surface, change the thermal radiation energy of equipment and personnel, and achieve cross-regional adaptive thermal stealth or decoy effect in a dynamic environment.

[0005] The technical solution adopted by the present invention is:

[0006] A dynamic thermal camouflage system applicable to complex uncontrolled environments includes

[0007] A thin film, covering a camouflaged object, has a liquid temperature-changing layer, which automatically regulates the temperature of the liquid inside it by liquid temperature-changing technology and fluid control, so as to control the surface temperature of the thin film;

[0008] A thermal camouflage response system, connected to the thin film through a liquid-conducting conduit, is used to control the temperature and flow direction of the fluid in the thin film, so that the camouflaged object attached with the thin film achieves a gradient temperature distribution in the infrared spectrum;

[0009] A thermal infrared characteristic analysis system, through multi-physical field coupling modeling of the camouflage thin film in a complex uncontrolled environment, obtains a multi-physical field coupling solver, and controls the thermal camouflage response system through signals.

[0010] The present invention has the following beneficial effects compared with the prior art:

[0011] The present invention is applied under the influence of solar radiation, wind, rain and fog on the surface temperature field of the camouflaged object, and performs stealth or false indication in the thermal infrared band, and can form a thermal camouflage thin film that can accurately regulate the thermal radiation energy of the camouflaged object in real time in a complex uncontrolled environment, comprehensively improving the dynamic camouflage performance. Description of the Drawings

[0012] Figure 1 is a schematic structural diagram of the present invention;

[0013] Figure 2 is a schematic diagram of the principle of the thermal infrared characteristic analysis system and the thermal camouflage response system of the present invention;

[0014] Figure 3 is a schematic diagram of the structure principle of the thin film of the present invention;

[0015] Figure 4 is an effect diagram of the temperature response of the thin film under the dynamic infrared background of the present invention;

[0016] Among them: 1. Thin film; 2. Thermal infrared characteristic analysis system; 3. Thermal camouflage response system; 101. Aerogel heat insulation layer; 102. Liquid temperature-changing layer; 103. PET anti-volatilization layer; 104. ITO low-emissivity deposition layer; 201. Computer; 202. Infrared camera; 203. Photovoltaic meteorological station; 301. Temperature sensor; 302. Heating device; 303. Liquid storage box A; 304. Refrigeration device; 305. Water pump B; 306. Liquid storage box B; 307. Overflow valve; 308. Water pump A; 309. Check valve; 310. Electromagnetic switch valve; 311. Flow sensor; 312. Proportional valve; 313. Controller. Detailed Embodiments

[0017] In order to better understand the purpose, structure and function of the present invention, the following further detailed description of the present invention is made in conjunction with the drawings.

[0018] As shown Figure 1 in the figure, the present invention provides a dynamic thermal camouflage system applicable to complex uncontrolled environments, comprising: a thin film 1, covering a camouflaged object, having a liquid temperature-changing layer 102, automatically regulating the temperature of the liquid inside it by liquid temperature-changing technology and fluid control, so as to control the surface temperature of the thin film 1;

[0019] a thermal camouflage response system 3, connected to the thin film 1 through a liquid-conducting catheter, for controlling the temperature and flow direction of the fluid in the thin film 1, so that the camouflaged object attached to the thin film 1 achieves a gradient temperature distribution in the infrared spectrum;

[0020] a thermal infrared characteristic analysis system 2, obtaining a multi-physical field coupling solver through multi-physical field coupling modeling of the camouflage thin film in a complex uncontrolled environment, and controlling the thermal camouflage response system 3 through signals.

[0021] In order to develop a multifunctional composite film with heat insulation, temperature regulation, anti-volatilization performance and low emissivity, researchers have extensively explored material and structure designs. Traditional heat insulation materials usually cannot simultaneously possess multiple functions such as temperature regulation, anti-volatilization and low emissivity, which limits their effectiveness in high-demand applications. For this reason, aerogels have been widely used due to their excellent heat insulation performance, while liquid temperature-changing materials can adjust their thermal properties according to environmental temperature changes to achieve active temperature regulation.

[0022] In the field of thermal camouflage flexible films, silicone rubber has become an ideal substrate due to its biocompatibility, high optical transparency and excellent tensile properties. However, silicone rubber materials generally have the disadvantage of large water vapor transmission rate, resulting in easy outward volatilization of the liquid inside the film when the contact area between the film and air is large, which in turn affects the continuity of the liquid circulation inside the film. To solve this problem, PET (polyethylene terephthalate) film is selected to prevent liquid volatilization with its excellent anti-volatilization performance to ensure the long-term stability of the film. At the same time, the ITO (indium tin oxide) layer, with its low emissivity characteristics, significantly reduces the infrared radiation of the target object surface after being coated with the ITO layer, reducing the possibility of being detected. Especially in thermal camouflage applications, the ITO layer can make the thermal signal of the camouflaged object close to the background environment and difficult to be distinguished by detectors, thus achieving a stealth effect. The ITO layer can be combined with other materials (such as PET, silicone rubber, etc.) to form a composite film. By combining these functional layers, an integrated composite film structure is formed, enabling this material to exhibit excellent comprehensive performance in thermal camouflage applications.

[0023] As shown Figure 3As shown in the figure, the film 1 of the present invention is a composite film with heat insulation performance, temperature regulation, anti-volatilization performance and low emissivity. The structure of the film 1 from bottom to top is an aerogel heat insulation layer 101, a liquid temperature-changing layer 102, a PET anti-volatilization layer 103, and an ITO low emissivity deposition layer 104. The PET anti-volatilization layer 103 and the ITO low emissivity deposition layer 104 are compounded on the Ecoflex surface to form a PET-ITO / Ecoflex composite layer. The aerogel heat insulation layer 101 and the liquid temperature-changing layer 102 are sealed by an Ecoflex base film, and the lower surface of the aerogel heat insulation layer 101 is sealed by an Ecoflex base film.

[0024] The structure of the aerogel heat insulation layer 101 of the film 1 is as follows: a plurality of downwardly concave grooves are formed on the surface of the Ecoflex film, and aerogel particles are filled in the grooves. The cross-section of each groove is circular, effectively preventing the aerogel from falling off.

[0025] The liquid temperature-changing layer 102 of the film 1 automatically regulates the liquid temperature inside by liquid temperature-changing technology and fluid control, thereby controlling the surface temperature of the film 1;

[0026] The structure of the liquid temperature-changing layer 102 is: serpentine-distributed downwardly concave flow channels are formed on the surface of the Ecoflex film.

[0027] The manufacturing method of the film 1 is as follows:

[0028] S1. Form the aerogel heat insulation layer 101;

[0029] Topologically distributed grooves are formed on the surface of the Ecoflex film, and aerogel particles are filled in the grooves; the aerogel can be evenly filled in the topologically distributed groove structure, effectively preventing the aerogel from falling off, and forming the aerogel heat insulation layer 101 of the film 1. The filling of the aerogel improves the heat transfer mechanism of the heat insulation interlayer, so that the heat insulation interlayer has a lower thermal conductivity.

[0030] S2. Form the liquid temperature-changing layer 102;

[0031] Serpentine-distributed downwardly concave flow channels are formed on the surface of the Ecoflex film. A coating rod with a gap of 100 μm is used to scrape the prepolymer of EcoflexTM FAST on another pretreated Ecoflex base film at a scraping speed of 10 mm / s. The film 1 with serpentine-distributed downwardly concave flow channels is gently placed vertically on the Ecoflex base film with the prepolymer, and placed in an incubator at 75 °C for 5 min. After curing, the liquid temperature-changing layer 102 of the film 1 is formed;

[0032] S3. Seal the liquid temperature-changing layer 102 and the aerogel heat insulation layer 101 of the film 1;

[0033] To seal the liquid temperature-changing layer 102 and the aerogel thermal insulation layer 101 of the film 1, the coating methods on both sides of the film 1 are the same. A coating rod with a gap of 100 μm is used to scrape and coat the prepolymer of EcoflexTM FAST on the other side of the Ecoflex base film with the liquid temperature-changing layer 102, and the scraping speed is 10 mm / s. After the prepolymer on the Ecoflex base film presents a non-flowing semi-solid state, the Ecoflex base film with the prepolymer is gently placed vertically on the interlayer with aerogel particles and placed in an incubator at 75 °C for 5 min. After curing, the sealed film 1, the liquid temperature-changing layer 102 and the aerogel thermal insulation layer 101 are formed.

[0034] As a silicone rubber material, the Ecoflex film generally has the disadvantage of a large water vapor transmission rate. When the contact area between the film 1 and the air is large, the liquid inside the film is likely to volatilize outward, which in turn affects the continuity of the liquid circulation inside the film. To solve this problem, the PET (polyethylene terephthalate) film 1 is selected for preventing liquid volatilization with its excellent anti-volatilization performance to ensure the long-term stability of the film. At the same time, due to the low emissivity characteristics of the ITO (indium tin oxide) layer, after the ITO layer is coated on the surface of the target object, its infrared radiation is significantly reduced, reducing the possibility of being detected. Especially in thermal camouflage applications, the ITO layer can make the thermal signal of the camouflaged object close to the background environment and difficult to be distinguished by the detector, thus achieving the stealth effect. The ITO layer can be combined with other materials (such as PET, silicone rubber, etc.) to form a composite film. By combining these functional layers, an integrated composite film structure is formed, enabling this material to exhibit excellent comprehensive performance in thermal camouflage applications.

[0035] S4. Form a PET-ITO / Ecoflex composite layer;

[0036] Magnetron sputtering is usually used to deposit ITO on the PET substrate. First, the PET substrate is cleaned and dried, and then deposited in a vacuum chamber. By introducing argon gas (sometimes a small amount of oxygen is added), a plasma is formed between the target and the substrate. Argon ions hit the ITO target, sputtering ITO atoms or molecules onto the PET substrate. During this process, the substrate temperature needs to be kept low to prevent PET from deforming. After deposition, annealing treatment can be carried out to improve the crystal structure and electrical properties of the ITO film 1, forming the PET anti-volatilization layer 103 and the ITO low emissivity deposition layer 104. Then, the above coating method is used to compound PET and ITO on the surface of Ecoflex with the liquid temperature-changing layer 102 and the aerogel thermal insulation layer 101 of the film 1 to form a PET-ITO / Ecoflex composite layer.

[0037] Such as Figure 1As shown in the figure, the thermal infrared characteristic analysis system 2 includes a computer 201, an infrared camera 202 that transmits information with the computer 201, an image acquisition module, an image processing module, a programmable logic controller, a temperature sensor, a photovoltaic meteorological station 203, a meteorological station software platform, a signal generator, and a temperature adaptive compensation module.

[0038] The thermal infrared characteristic analysis system 2 obtains a multi-physical field coupling solver through multi-physical field coupling modeling of the camouflage film 1 in a complex uncontrolled environment, modularizes the thermal boundary conditions of the complex environment, provides a visual interactive operation interface, realizes the surface temperature calculation function of the thermal camouflage film 1 under different conditions, and generates the surface temperature of the film 1 under different conditions; generates temperature compensation between the liquid temperature and the set temperature of the film 1 area; generates a variable temperature signal and a fluid control signal.

[0039] The multi-physical field coupling solver modularizes the thermal boundary conditions of the complex environment, provides a visual interactive operation interface, realizes the surface temperature calculation function of the thermal camouflage film 1 under different conditions, and generates the surface temperature of the film 1 under different conditions; generates temperature compensation between the liquid temperature and the set temperature of the film 1 area; generates a variable temperature signal and a fluid control signal.

[0040] The multi-physical field coupling solver is composed of an environmental material parameter input module, a thermal boundary condition calculation model module, and a multi-physical field coupling solution module; among them:

[0041] The input parameters of the environmental material parameter input module include environmental parameters, meteorological conditions, geographical location, start and end times, material properties, and simulation configurations. The simulation configuration includes mesh division parameters, time step settings, initial and boundary conditions, numerical solution settings, physical field configurations, data output settings, heat source and fluid settings, as well as iteration and precision control, and is used to define and control the process and precision of the multi-physical field coupling simulation. The above parameters are obtained by the infrared camera 202, the image acquisition module, the image processing module, the programmable logic controller, the temperature sensor, the photovoltaic meteorological station 203, and the meteorological station software platform;

[0042] The thermal boundary condition calculation model module includes an environmental model, a heat conduction model, a heat convection model, a heat radiation model, an evaporation and cooling model. Each model in the above thermal boundary condition calculation model module is mainly implemented through multi-physical field simulation software, and combines numerical calculation and analytical methods to accurately describe the thermal boundary conditions in a complex environment.

[0043] Among them: The environmental model is used to simulate external meteorological conditions (such as temperature, humidity, wind speed, and solar radiation intensity), and provides basic data input for the thermal analysis of the entire system. Through this model, the thermal influence degree of the environment on the system can be obtained, and dynamic boundary conditions can be provided for subsequent heat conduction, convection, radiation, etc. calculations;

[0044] The heat conduction model is used to simulate the heat transfer inside and between materials, and calculate the temperature gradient and heat flux distribution;

[0045] The heat convection model is used to simulate the heat exchange between the solid surface and fluids (such as air, water, etc.), especially the enhancement of heat transfer in the presence of a flowing medium. This model is used to evaluate the influence of wind speed, air flow, etc. on the surface temperature of the thin film, especially the heat transfer efficiency in a high-convection environment;

[0046] The heat radiation model is used to describe the thermal radiation exchange between the object surface and the surrounding environment, and calculate the absorption and emission of the object's radiation energy. This model is crucial for the evaluation of camouflage effects under high or low temperature conditions, especially the influence of solar radiation and the object's spontaneous radiation;

[0047] Evaporation and cooling model: Simulate the evaporation of the liquid surface and the influence of the cooling process on the temperature distribution, and evaluate the regulating effect of factors such as fog and raindrops on the thermal characteristics of the system. This model can accurately describe how evaporation cooling affects the surface temperature of the thin film, especially in the thermal camouflage application in humid or rainy environments. These models work together to accurately predict the surface temperature of the thin film in a complex uncontrolled environment.”

[0048] The multi-physics coupling solution module includes a boundary parameter setting unit, a solution method unit, a solution control unit, a monitoring parameter unit, and an initialization unit.

[0049] Among them: The boundary parameter setting unit is used to define and configure the boundary conditions of the multi-physics problem;

[0050] The solution method unit selects a suitable numerical solution algorithm to handle the coupling problem;

[0051] The solution control unit is responsible for managing the iteration strategy, convergence criterion, and error control of the solution process;

[0052] The monitoring parameter unit monitors the changes of key physical parameters in real time to ensure the solution accuracy;

[0053] The initialization unit sets the initial conditions, speeds up the solution convergence speed, reduces the calculation time, and ensures the rationality of the multi-physics coupling solution.

[0054] In the process of multi-physical field coupling modeling of the camouflage film 1 in a complex uncontrolled environment in the thermal infrared characteristic analysis system 2, first, a simplified model of the heat and mass transfer process from the heat source to the film 1 is established to determine the thermal boundary conditions of the wind, rain, fog, and solar radiation on the camouflage object in the complex uncontrolled environment; determine the factors of its own heat conduction, convective heat transfer of the external heat source and thermal radiation, and the interaction between the internal fluid and the wall surface of the film 1; input the complex meteorological boundary conditions into the environment model, heat conduction model, heat convection model, thermal radiation model, evaporation and cooling model, and construct a multi-physical field coupling model through the coupling equation and joint solution to obtain a multi-physical field coupling solver; simulate the external thermal boundary conditions on the surface of the film 1 to realize the prediction of the temperature response of the film 1 under different meteorological conditions.

[0055] In the present invention, after the variable temperature signal is generated by the thermal infrared characteristic analysis system 2, the camouflage film 1 is connected to the thermal camouflage response system 3, and the temperature and flow direction of the fluid in the film 1 are controlled by the refrigeration device 304, heating device 302, temperature sensor 301, flow sensor 311, water pump A308, overflow valve 307, one-way valve 309, electromagnetic solenoid valve 310, proportional valve 312, etc., so that the camouflage object attached to the film 1 realizes a gradient temperature distribution in the infrared spectrum.

[0056] As Figure 2 shown, the usage method of the thermal infrared characteristic analysis system 2 is as follows:

[0057] Calculate the surface temperature of the film 1 through the multi-physical field coupling solver to generate the set temperature value T FN and the flow rate set value q N ; after that, the signal generator generates a temperature control signal based on the set temperature value of the film 1, and the controller 313 controls the liquid temperature; after the liquid temperature reaches the set value T FN , the signal generator generates a flow control signal based on the flow rate set value of the film 1, controls the inlet flow rate, and adjusts the flow rate to synchronously realize the temperature response in different regions on the film 1.

[0058] Collect the surface temperature T' FN of the film 1 through the infrared camera 202, and transmit the collected temperature information to the signal generator. If T' FN = T FN , then keep the liquid circulating; if T' FN ≠ T FN , then enter the temperature adaptive compensation module; generate the liquid temperature compensation T LN by the temperature adaptive compensation module; the signal generator generates a temperature signal based on the liquid temperature compensation value, and the controller 313 calculates and outputs a current drive signal according to the collected temperature signal in combination with the liquid temperature output by the liquid storage box A303 to automatically change the compensation amount.

[0059] Transfer the variable temperature signal and the fluid control signal to the thermal camouflage response system 3, and the thermal camouflage response system 3 controls the temperature and flow direction of the fluid in the thin film 1. The thermal camouflage response system 3 controls the temperature and flow direction of the fluid in the thin film 1 through the generated variable temperature signal and fluid control signal, so that the target attached to the thin film 1 is stealthy in the infrared spectrum;

[0060] As Figure 1 shown, the thermal camouflage response system 3 includes a temperature sensor 301, a heating device 302, a liquid storage box A 303, a refrigeration device 304, a water pump B 305, a liquid storage box B 306, an overflow valve 307, a water pump A 308, a check valve 309, an electromagnetic switching valve 310, a flow sensor 311, a proportional valve 312 and a controller 313; a refrigeration device 304 and a heating device 302 are installed on the liquid storage box A 303, a temperature sensor 301 is installed in the liquid storage box A 303, the inlet end of the water pump A 308 is communicated with the liquid storage box A 303, the outlet end of the water pump A 308 is communicated with the flow path inlet of the liquid temperature change layer 102 of the thin film 1 through a pipeline, and a proportional valve 312, a flow sensor 311, an electromagnetic switching valve 310 and a check valve 309 are installed on the pipeline, an overflow pipe is communicated between the liquid storage box A 303 and the pipeline, an overflow valve 307 is installed on the overflow pipe, a liquid storage box B 306 is installed between the flow path outlet of the liquid temperature change layer 102 of the thin film 1 and the inlet end of the water pump B 305, the outlet end of the water pump B 305 is communicated with the liquid storage box A 303, and the refrigeration device 304, the heating device 302, the temperature sensor 301, the proportional valve 312, the flow sensor 311, the electromagnetic switching valve 310, the check valve 309, the overflow valve 307, the water pump A 308 and the water pump B 305 are all controlled by the controller 313.

[0061] The thermal camouflage response system 3 includes two closed-loop feedback control loops, which are respectively used for liquid temperature control and flow control. Each component of the refrigeration device 304 is driven by a programmable power supply, and functions such as liquid temperature regulation and flow regulation in the thermal camouflage response system 3 are all realized through the control system of the controller 313. The microcontroller of the controller 313 obtains the temperature set value T N, the liquid temperature data is collected into the single-chip microcomputer through the analog-to-digital conversion module A / D. The single-chip microcomputer receives the set temperature given by the algorithm and detects the liquid temperature in the liquid storage box A303 through the temperature sensor 301 in the liquid storage box A303. According to the difference between the temperature in the liquid storage box A303 and the temperature of the camouflage object, a temperature control signal is output to adjust the power of the heating device 302 and the refrigeration device 304. When the liquid temperature reaches the set value, a switch control signal is sent to control the opening of the water pump A308, and the temperature response of different temperature regions of the film 1 is controlled by the measured temperature data of the current film 1 of the measurement system of the controller 313, achieving the effect of adaptive gradient temperature distribution. As the thermal boundary conditions change, the film 1 undergoes a temperature response, making the temperature gradient distribution on the surface of the camouflage object consistent with that of the background, realizing the adaptive adjustment of the camouflage film 1.

[0062] When the film 1 covers the surface of the heat source target, temperature adaptive compensation is used to compensate for the difference between the liquid temperature output by the liquid storage box A303 and the actual temperature of the film 1. By collecting the surface temperature of the film 1, the collected temperature information is transmitted to the main controller module of the controller 313; according to the collected temperature signal and combined with the liquid temperature output by the liquid storage box A303, the temperature compensation amount is calculated by the temperature calculation integrated software of the controller 313, and the main controller 313 module calculates and outputs a current drive signal to automatically change the compensation amount; the temperature compensation module receives the drive signal output by the main controller 313 module, changes the power of the heating device 302 and the refrigeration device 304 to change the liquid temperature, achieving the purpose of temperature adaptive compensation.

[0063] According to the key parameters such as solar radiation intensity, ambient temperature, and wind speed under sunny, rainy, and foggy weather conditions in the present invention, the thermal boundary conditions of the complex environment are modularized, and its own heat conduction, boundary conditions, convective heat transfer and thermal radiation of external heat sources, and the interaction factors between the internal fluid and the wall surface of the film 1 are determined. The complex meteorological boundary conditions are input into the environmental model, heat conduction model, heat convection model, thermal radiation model, evaporation and cooling model, and a multi-physical field coupling model is constructed through coupled equations and joint solutions to obtain a multi-physical field coupling solver; the location of heat transfer in the complex uncontrolled environment with complex calculations is selected, and combined with the actual situation of the annual climate conditions in the selected area, the influence of meteorological parameters on the thermal infrared characteristics of the film 1 under sunny, rainy, and foggy weather conditions is calculated and analyzed; under the environmental conditions in summer and winter, the temperature difference between the surface temperature of the film 1 and the camouflage target is analyzed to determine the optimal volume flow rate in each season and the temperature distribution characteristics when the temperature difference is the largest.

[0064] As Figure 4 shown. In the present invention, the change process of the infrared characteristics of the film 1 attached to the 60 °C heat source target in the dynamic infrared background is as Figure 4(a) As shown. The thermal infrared characteristic analysis system 2 collects the film 1 in the closed state (left image), turns on the thermal camouflage response system 3, and the infrared characteristics of the film 1 blend into the background (middle image); when moving forward, the infrared camera 202 captures the background images at three temperatures, and the liquid temperature set value is obtained through the thermal infrared characteristic analysis system 2; through temperature control and flow control feedback, the liquid pumps at three temperatures are driven into the film 1 to achieve adaptive temperature change during the moving process (right image). In order to evaluate the temperature change effect of the film 1, a pixel-temperature distribution map is introduced to evaluate the effectiveness of the film 1 for zonal temperature control. The infrared image has the characteristics of intuitive visualization and can well reflect the thermal infrared difference characteristics between the target and the background. According to the gradient characteristics of the infrared image, the more obvious the transition between the target and the background, the more obvious the target is. Figure 4 (b) shows the pixel-temperature distribution of the heat source target in the infrared background before and after the thermal camouflage response system 3 is turned on. It can be seen from the figure that there is a large temperature gradient between the background and the heat source target before the temperature response, making the target easy to be detected. After the temperature response, the target and the background have a continuous and flat temperature gradient, and there is no significant bulge on the three-dimensional distribution surface. The infrared image shows that the temperature-changing film 1 can generate a gradient temperature distribution similar to the background, fusing the thermal infrared characteristics of the target and the background together. When the film 1 does not cover the heat source, by changing the temperature of the background board, the change of the infrared characteristics of the film 1 is as Figure 4 (c) As shown, the thermal infrared characteristic analysis system 2 collects the film 1 in the closed state (left image); turns on the thermal camouflage response system 3, and with the change of the temperature of the pumped liquid, the infrared characteristics of the front area of the film 1 blend into the background again (middle image); when the temperature of the middle area of the background board rises, the thermal camouflage response system 3 automatically generates a temperature response, heats the liquid in the corresponding area of the liquid storage box, and the liquid heats up and fills into the film 1, making the film 1 blend more naturally with the background in the infrared spectrum (right image).

[0065] It can be understood that the present invention is described through some embodiments. Those skilled in the art know that without departing from the spirit and scope of the present invention, various changes or equivalent replacements can be made to these features and embodiments. In addition, under the teaching of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application belong to the scope protected by the present invention.

Claims

1. A dynamic thermal camouflage system suitable for use in complex uncontrolled environments, characterized by: include: The film (1) is covered on the camouflaged object and has a liquid temperature-changing layer (102) which automatically adjusts the temperature of the liquid inside the film (1) by using liquid temperature-changing technology and fluid control, thereby controlling the surface temperature of the film (1); The thermal camouflage response system (3) is connected to the film (1) through a fluid conduit and is used to control the temperature and flow direction of the fluid in the film (1) so that the camouflaged object attached to the film (1) can achieve a gradient temperature distribution in the infrared spectrum; Thermal infrared characteristic analysis system (2), through multi-physics coupling modeling of camouflage film in complex uncontrolled environment, obtain multi-physics coupling solver, and control thermal camouflage response system (3) through signal, The film (1) has a structure from bottom to top of an aerogel insulation layer (101), a liquid temperature-variable layer (102), a PET anti-volatile layer (103), and an ITO low-emissivity deposition layer (104); the PET anti-volatile layer (103) and the ITO low-emissivity deposition layer (104) are composited on the surface of Ecoflex to form a PET-ITO / Ecoflex composite layer; the aerogel insulation layer (101) and the liquid temperature-variable layer (102) are sealed by an Ecoflex base film; the lower surface of the aerogel insulation layer (101) is sealed by an Ecoflex base film; The structure of the aerogel heat insulation layer (101) of the film (1) is as follows: a plurality of downwardly sunken grooves are provided on the surface of the Ecoflex film, the grooves are filled with aerogel particles, and the cross section of each groove is circular.

2. According to claim 1, a dynamic thermal camouflage system suitable for use in complex uncontrolled environments is characterized by: The structure of the liquid temperature-changing layer (102) is as follows: a downwardly concave flow channel distributed in a serpentine shape is provided on the surface of the Ecoflex membrane.

3. According to claim 2, a dynamic thermal camouflage system suitable for use in complex uncontrolled environments is characterized by: The method for preparing the film (1) is as follows: S1. Forming an aerogel insulation layer (101); A downwardly concave groove is provided on the surface of the Ecoflex membrane, and aerogel particles are filled in the groove; S2. Forming a liquid temperature variable layer (102); A serpentine-shaped downwardly concave flow channel is opened on the surface of the Ecoflex film, and the EcoflexTM FAST prepolymer is scraped onto another pre-treated Ecoflex base film using a coating rod, and the film (1) with the serpentine-shaped downwardly concave flow channel is vertically and gently placed on the Ecoflex base film with the prepolymer, and placed in a constant temperature box for curing; S3. The liquid temperature-changing layer (102) and the aerogel insulation layer (101) of the sealing film (1); Using a coating rod, the prepolymer of EcoflexTM FAST is scraped onto the other side of the Ecoflex base film with the liquid temperature-variable layer (102), and the Ecoflex base film with the prepolymer is vertically and gently placed on the interlayer with the aerogel particles, and placed in a constant temperature box for curing; S4. forming a PET-ITO / Ecoflex composite layer; First, the PET substrate is cleaned and dried, and then deposited in a vacuum chamber. By introducing argon gas, plasma is formed between the target material and the substrate. Argon ions collide with the ITO target material, and ITO atoms or molecules are sputtered onto the PET substrate. After the deposition is completed, annealing is performed to form a PET anti-volatile layer (103) and an ITO low-emissivity deposition layer (104). Then, the PET and ITO are composited on the Ecoflex surface having a thin film (1), a liquid temperature-variable layer (102) and an aerogel insulation layer (101) using the above coating method to form a PET-ITO / Ecoflex composite layer.

4. According to claim 1, a dynamic thermal camouflage system suitable for use in complex uncontrolled environments is characterized by: The thermal infrared characteristic analysis system (2) comprises a computer (201), an infrared camera (202) for transmitting information to the computer (201), an image acquisition module, an image processing module, a programmable logic controller, a temperature sensor, a photovoltaic weather station (203), a weather station software platform, a signal generator, and a temperature adaptive compensation module.

5. According to claim 4, a dynamic thermal camouflage system suitable for use in complex uncontrolled environments is characterized by: The thermal infrared characteristic analysis system (2) obtains a multi-physical field coupling solver by multi-physical field coupling modeling of the camouflage film (1) under a complex uncontrolled environment. The multi-physics coupling solver consists of an environmental material parameter input module, a thermal boundary condition calculation model module, and a multi-physics coupling solving module; The input parameters of the environmental material parameter input module include environmental parameters, meteorological conditions, geographical location, start and end time, material properties and simulation configuration; The thermal boundary condition calculation model module includes an environment model, a heat conduction model, a heat convection model, a heat radiation model, and an evaporation and cooling model; The multi-physics field coupling solution module includes a boundary parameter setting unit, a solution method unit, a solution control unit, a monitoring parameter unit and an initialization unit.

6. According to claim 5, a dynamic thermal camouflage system suitable for use in complex uncontrolled environments is characterized by: The method for using the thermal infrared characteristic analysis system (2) is as follows: The surface temperature of the film (1) is calculated by a multi-physics coupling solver to generate the set temperature T of each area of ​​the film (1). N After that, the liquid compensation temperature T L , generating a temperature change signal and a fluid control signal, and transmitting the temperature change signal and the fluid control signal to a thermal camouflage response system (3), and the thermal camouflage response system (3) controls the temperature and flow direction of the fluid in the film (1).

7. According to claim 1, a dynamic thermal camouflage system suitable for use in complex uncontrolled environments is characterized by: The thermal camouflage response system (3) comprises a temperature sensor (301), a heating device (302), a liquid storage box A (303), a refrigeration device (304), a water pump B (305), a liquid storage box B (306), an overflow valve (307), a water pump A (308), a one-way valve (309), an electromagnetic switch valve (310), a flow sensor (311), a proportional valve (312) and a controller (313); the liquid storage box A (303) is installed with a refrigeration device (304) and a heating device (302); the liquid storage box A (303) is installed with a temperature sensor (301); the inlet end of the water pump A (308) is connected to the liquid storage box A (303); the outlet end of the water pump A (308) is connected to the flow channel inlet of the liquid temperature variable layer (102) of the film (1) through a pipeline, and the pipeline is A proportional valve (312), a flow sensor (311), an electromagnetic switch valve (310) and a one-way valve (309) are installed; an overflow pipe is connected between the liquid storage box A (303) and the pipeline, and an overflow valve (307) is installed on the overflow pipe; a liquid storage box B (306) is installed between the flow channel outlet of the liquid temperature-changing layer (102) of the film (1) and the inlet end of the water pump B (305); the outlet end of the water pump B (305) is connected to the liquid storage box A (303); the refrigeration device (304), the heating device (302), the temperature sensor (301), the proportional valve (312), the flow sensor (311), the electromagnetic switch valve (310), the one-way valve (309), the overflow valve (307), the water pump A (308) and the water pump B (305) are all controlled by a controller (313).

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