Airborne supercooled water and ice crystal phase state distinguishing and content measuring system
By using laser depolarization effect to distinguish and measure the content of supercooled water and ice crystals through light emission and reception components, the problem of not being able to detect icing in advance in existing technologies is solved, and safe flight warning and lightweight equipment design are achieved.
Patent Information
- Application Number
- CN202511992320.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-26
- Publication Date
- 2026-03-27
AI Technical Summary
Existing aircraft icing detectors cannot detect supercooled large water droplets and ice crystals in advance, which may cause the aircraft to issue a warning only after severe icing has occurred, posing a safety hazard.
Using optical emission and reception components, and leveraging the reflection principle of linearly polarized lasers and polarizing prisms, the phase state and content of supercooled water and ice crystals are distinguished and measured through the laser depolarization effect. Combined with signal processing components, their proportion or content is calculated.
It can remind pilots to fly cautiously before the aircraft enters an icing environment, thus avoiding safety accidents caused by icing. The device is small in size, light in weight, and has low power consumption, making it suitable for installation on aircraft.
Smart Images
Figure CN121740764A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of meteorological monitoring, and in particular to an airborne system for distinguishing the phases and measuring the content of supercooled water and ice crystals. Background Technology
[0002] In the aviation field, large civilian aircraft currently rely primarily on resonant icing detectors for icing detection and warning. The main principle is to detect icing by utilizing the decrease in vibration frequency of the detector's sensing element after icing. In addition to resonant icing detectors, large military aircraft also use fiber optic and flat-film icing detectors. Although their specific measurement principles differ, they all rely on changes in certain characteristics caused by icing to detect icing. This detection method has the following drawbacks: (1) The alarm is only issued after the detector's sensitive parts are iced. At this time, the aircraft wings and other parts may already be severely iced. If the pilot is not careful, it may lead to a crash and loss of life.
[0003] (2) It cannot detect the freezing of supercooled large water droplets and ice crystals. Currently, the resonant icing detectors of companies such as Rosemount can only detect the freezing of supercooled water droplets below 50um, and cannot detect the freezing of supercooled large water droplets and ice crystals. Summary of the Invention
[0004] In view of this, this application provides an airborne system for distinguishing the phases of supercooled water and ice crystals and measuring their content, which solves the problems in the prior art and enables early warning of flight icing environments in the aviation field. The airborne subcooled water and ice crystal phase differentiation and content measurement system provided in this application adopts the following technical solution: An airborne system for distinguishing the phase states and measuring the content of supercooled water and ice crystals includes a light emitting component, a light receiving component, and a signal processing component; The light emitting component is used to emit linearly polarized laser light that illuminates the detection area of the aircraft's external environment. The light receiving component includes a polarizing prism, a first converging lens, and a second converging lens. The polarizing prism has a polarizer, and the angle between the polarizer and the light-receiving surface of the polarizing prism is 45 degrees. The first converging lens is located on the path of the reflected light from the polarizer, and the second converging lens is located on the side of the polarizer facing away from the light-receiving surface of the polarizing prism. A first photodetector is located on the side of the first converging lens facing away from the polarizing prism, and a second photodetector is located on the side of the second converging lens facing away from the polarizing prism. The first photodetector is used to receive the light emitted from the first converging lens, and the second photodetector is used to receive the light emitted from the second converging lens. After being reflected by supercooled water or ice crystals, the linearly polarized laser enters the light receiving component. The polarized light entering the polarizing prism is reflected by the polarizer to the first converging lens, and the depolarized light entering the polarizing prism passes through the polarizer to reach the second converging lens. The signal processing component is used to calculate the ratio or content of cold water and ice crystals based on the light energy received by the first photodetector and the second photodetector.
[0005] Optionally, the light emitting assembly includes a laser emitter, a first negative lens, and a positive lens. The polarizer emitted by the laser emitter is diverged by the negative lens and then converted into parallel light by the positive lens.
[0006] Optionally, the laser emitter emits polarized light with a wavelength of 1550 nm.
[0007] Optionally, the light receiving component further includes a converging objective, a second negative lens, and a filter. The converging objective is used to receive reflected light from the detection area and converge it to the second negative lens. The second negative lens converts the light emitted from the converging objective into parallel light. The filter is located between the second negative lens and the polarizing prism. The filter filters out light with a wavelength other than 1550nm and allows light with a wavelength of 1550nm to pass through.
[0008] Optionally, the first converging lens and the second converging lens are aspherical lenses, the first photodetector is located at the real focal point of the first converging lens, and the second photodetector is located at the real focal point of the second converging lens.
[0009] Optionally, the first photodetector and the second photodetector are indium gallium arsenide avalanche photodiodes.
[0010] Optionally, the receiving end of the light receiving component is provided with light-transmitting glass, and the light-transmitting glass is provided with a transparent heating mold, which is used to heat the light-transmitting glass.
[0011] Optionally, the airborne supercooled water and ice crystal phase differentiation and content measurement system also includes a power supply component, which supplies power to the light emitting component, the light receiving component, and the signal processing component. The signal processing component is used to drive the semiconductor cooling chip of the laser to heat or cool according to the laser temperature sensor of the light emitting component, so that the laser is maintained at a preset operating temperature.
[0012] In summary, this application includes the following beneficial technical effects: This application utilizes laser depolarization technology to directly measure the content of supercooled water and ice crystals in clouds. Compared to resonant icing detectors, it can issue icing warnings as soon as a large aircraft enters an icing environment, reminding pilots to fly with caution. Compared to cloud precipitation particle imagers, it is smaller, lighter, has lower aerodynamic drag, and lower power consumption, making it suitable for close mounting on aircraft skin. Attached Figure Description
[0013] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0014] Figure 1 A schematic diagram of the principle of an airborne subcooled water and ice crystal phase differentiation and content measurement system; Figure 2 This is a schematic diagram of the structure of the light emitting component; Figure 3 This is a schematic diagram of the optical receiving component.
[0015] Explanation of reference numerals in the attached figures: 1. Laser emitter; 11. First negative lens; 12. Positive lens; 2. Polarizing prism; 21. Polarizer; 22. First converging lens; 23. Second converging lens; 24. First photodetector; 25. Second photodetector; 26. Converging objective lens; 27. Second negative lens; 28. Filter. Detailed Implementation
[0016] The embodiments of this application will now be described in detail with reference to the accompanying drawings.
[0017] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0018] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this application, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.
[0019] It should also be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this application. The illustrations only show the components related to this application and are not drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.
[0020] Furthermore, specific details are provided in the following description to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that the described aspects can be practiced without these specific details.
[0021] This application provides an airborne system for distinguishing the phases of supercooled water and ice crystals and measuring their content.
[0022] like Figures 1 to 3 As shown, an airborne system for distinguishing the phases and measuring the content of supercooled water and ice crystals includes a light emitting component, a light receiving component, and a signal processing component.
[0023] The light emitting component is used to emit linearly polarized laser light that illuminates the detection area of the aircraft's external environment. The light receiving component includes a polarizing prism 2, a first converging lens 22, and a second converging lens 23. The polarizing prism 2 has a polarizer 21, and the angle between the polarizer 21 and the light-receiving surface of the polarizing prism 2 is 45 degrees. The first converging lens 22 is located on the path of the reflected light from the polarizer 21. The second converging lens 23 is located on the side of the polarizer 21 that is away from the light-receiving surface of the polarizing prism 2. A first photodetector 24 is provided on the side of the first converging lens 22 that is away from the polarizing prism 2, and a second photodetector 25 is provided on the side of the second converging lens 23 that is away from the polarizing prism 2. The first photodetector 24 is used to receive the emitted light from the first converging lens 22, and the second photodetector 25 is used to receive the emitted light from the second converging lens 23.
[0024] Linearly polarized laser light enters the light receiving component after being reflected by supercooled water or ice crystals. The polarized light entering the polarizing prism 2 is reflected by the polarizer 21 to the first converging lens 22. The depolarized light entering the polarizing prism 2 passes through the polarizer 21 to reach the second converging lens 23. The signal processing component is used to calculate the ratio or content of cold water and ice crystals based on the light energy received by the first photodetector 24 and the second photodetector 25.
[0025] This application is based on the laser depolarization effect. According to the scattering theory of spherical particles, assuming that the scattering particles are spherical and isotropic, when the irradiating light is linearly polarized, the scattered light is also linearly polarized with the same direction of vibration as the incident photoelectric vector. The scattered light from non-spherical particles will no longer be completely polarized, i.e., a depolarization effect occurs. Utilizing the depolarization information and echo capability of the scattered electromagnetic radiation, the proportion and content of spherical and non-spherical particles can be detected and distinguished. In practical engineering, we consider small water droplets as spherical particles and small ice crystals as non-spherical particles. Polarized light irradiating ice crystals undergoes depolarization; therefore, the higher the proportion of polarized light energy received by the second photodetector 25, the more ice crystals are present in the environment.
[0026] The light emitting assembly includes a laser emitter 1, a first negative lens 11, and a positive lens 12. The polarizer emitted by the laser emitter 1 is diverged by the negative lens and then converted into parallel light by the positive lens 12.
[0027] The laser emitter 1 emits polarized light with a wavelength of 1550 nm.
[0028] The light receiving assembly also includes a converging objective lens 26, a second negative lens 27, and a filter 28. The converging objective lens 26 is used to receive reflected light from the detection area and converge it to the second negative lens 27. The second negative lens 27 converts the light emitted from the converging objective lens 26 into parallel light. The filter 28 is located between the second negative lens 27 and the polarizing prism 2. The filter 28 filters out light with a wavelength other than 1550nm and allows light with a wavelength of 1550nm to pass through.
[0029] The first converging lens 22 and the second converging lens 23 are aspherical lenses. The first photodetector 24 is located at the real focal point of the first converging lens 22, and the second photodetector 25 is located at the real focal point of the second converging lens 23.
[0030] The first photodetector 24 and the second photodetector 25 are indium gallium arsenide avalanche photodiodes (InGaAs APDs). The InGaAs APD converts the optical signal into a current signal, which is then output to the signal processing component for signal acquisition and processing. The signal processing component converts the current signal into a voltage signal for AD acquisition, calculating the polarization energy corresponding to the water droplet and the depolarization energy corresponding to the ice crystal. Calibration is then used to determine the liquid water content and ice crystal content.
[0031] The light receiving component has a light-transmitting glass at its receiving end, and a transparent heating mold is provided on the light-transmitting glass. The transparent heating mold is used to heat the light-transmitting glass to ensure that the inside of the light receiving component will not freeze due to water vapor condensation.
[0032] The airborne supercooled water and ice crystal phase differentiation and content measurement system also includes a power supply component, which supplies power to the light emitting component, the light receiving component, the signal processing component and the transparent heating film. The signal processing component is used to drive the semiconductor cooling chip of the laser to heat or cool according to the laser temperature sensor of the light emitting component, so that the laser is maintained at a preset operating temperature.
[0033] Specifically, the power supply component converts the 28V power supplied from the machine into 15VDC after passing through surge protection circuits, voltage spike suppression circuits, reverse connection protection circuits, filtering circuits, and DC / DC power conversion circuits to drive the laser. It also has laser temperature control and transparent heating film temperature control functions. The signal processing component outputs a laser temperature control signal to the power supply component to control the laser to output a certain frequency of laser light; it collects the temperature of the laser's NTC sensor to drive the power supply component to control the heating / cooling of the laser's semiconductor cooling chip, ensuring the laser operates within a certain temperature range; the signal processing component collects the window glass temperature to control internal heating.
[0034] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. An airborne supercooled water and ice crystal phase discrimination and content measurement system characterized by, The light emitting component, the light receiving component and the signal processing component are included. The light emitting component is used for emitting linearly polarized laser irradiated on the detection area of the external environment of the airplane, the light receiving component includes a polarizing prism (2), a first converging lens (22) and a second converging lens (23), the polarizing prism (2) is provided with a polarizer (21), the included angle between the polarizer (21) and the light receiving surface of the polarizing prism (2) is 45 degrees, the first converging lens (22) is located on the path of the reflected light of the polarizer (21), the second converging lens (23) is located on the side of the polarizer (21) away from the light receiving surface of the polarizing prism (2), the first converging lens (22) is provided with a first photodetector (24) on the side away from the polarizing prism (2), the second converging lens (23) is provided with a second photodetector (25) on the side away from the polarizing prism (2), the first photodetector (24) is used for receiving the emergent light of the first converging lens (22), and the second photodetector (25) is used for receiving the emergent light of the second converging lens (23). The linearly polarized laser enters the light receiving component after being reflected by supercooled water or ice crystals, and the polarized light entering the polarizing prism (2) is reflected to the first converging lens (22) through the polarizer (21), and the depolarized light entering the polarizing prism (2) passes through the polarizer (21) to reach the second converging lens (23). The signal processing component is used for calculating the proportion or content of the supercooled water and the ice crystals according to the light energy received by the first photodetector (24) and the second photodetector (25).
2. The airborne supercooled water and ice crystal phase discrimination and content measurement system of claim 1, wherein, The light emitting component includes a laser emitter (1), a first negative lens (11) and a positive lens (12), and the polarized tube emitted by the laser emitter (1) is converted into parallel light by the positive lens (12) after being diverged by the negative lens.
3. The airborne supercooled water and ice crystal phase discrimination and content measurement system of claim 2, wherein, The wavelength of the polarized light emitted by the laser emitter (1) is 1550nm.
4. The airborne supercooled water and ice crystal phase discrimination and content measurement system of claim 3, wherein, The light receiving component further includes a converging objective lens (26), a second negative lens (27) and a filter (28), the converging objective lens (26) is used for receiving the reflected light of the detection area and converging to the second negative lens (27), the second negative lens (27) converts the emergent light of the converging objective lens (26) into parallel light, and the filter (28) is located between the second negative lens (27) and the polarizing prism (2), the filter (28) filters out light rays other than 1550nm wavelength and allows 1550nm wavelength light rays to pass through.
5. The airborne supercooled water and ice crystal phase discrimination and content measurement system of claim 1, wherein, The first converging lens (22) and the second converging lens (23) are aspherical lenses, the first photodetector (24) is located on the real focus of the first converging lens (22), and the second photodetector (25) is located on the real focus of the second converging lens (23).
6. The airborne supercooled water and ice crystal phase discrimination and content measurement system of claim 1, wherein, The first photodetector (24) and the second photodetector (25) are indium gallium arsenide avalanche photodiodes.
7. The airborne supercooled water and ice crystal phase discrimination and content measurement system of claim 1, wherein, A light-transmitting glass is arranged on the receiving end of the light receiving component, a transparent heating mold is arranged on the light-transmitting glass, and the transparent heating mold is used for heating the light-transmitting glass.
8. The airborne supercooled water and ice crystal phase discrimination and content measurement system of claim 1, wherein, The airborne supercooled water and ice crystal phase state distinguishing and content measuring system further comprises a power supply assembly for supplying power to the light emitting assembly, the light receiving assembly and a signal processing assembly, the signal processing assembly being configured to drive the semiconductor refrigerating sheet of the laser of the light emitting assembly to heat or refrigerate according to the temperature sensor of the laser, so as to maintain the laser at a preset working temperature.