Super-cooled large droplet detector

Abstract

A super-cooled large droplet detector, which can accurately and reliably identify and distinguish super-cooled large droplet freezing weather. The super-cooled large droplet detector comprises a detector base and a detection structure, wherein the detection structure is used for detecting super-cooled droplets in airflow and for identifying freezing weather and distinguishing super-cooled large droplet freezing weather from the freezing weather; an outer layer of the detection structure is a temperature sensor layer, an intermediate layer thereof is an electric heating film layer, and an inner layer thereof is a structure substrate; the electric heating film layer provides heating energy by means of a plurality of electric heating loops, such that the surface of the detection structure maintains at a uniform temperature; the temperature sensor layer is provided with a plurality of temperature sensors; and a controller is provided in the structure substrate, and the controller infers an impact range of the super-cooled droplets by means of temperature changes, which are caused by the super-cooled large droplets impacting the detection structure, at a plurality of different positions, and determines, by means of determining whether the impact range exceeds a critical impact range obtained when the super-cooled droplets exceeding a critical size impact the detection structure, whether the previous impacting super-cooled droplets are super-cooled large droplets.

Description

Supercooled large water droplet detector Technical Field

[0001] The present invention relates to a supercooled large water droplet detector, in particular to a supercooled large water droplet detector having a (for example, spherical) detection structure, which is used to identify and distinguish supercooled large water droplet freezing weather and belongs to the field of ice detection. Background Art

[0002] The aviation industry has strict requirements on icing weather because icing weather can endanger the safety of aircraft and may pose serious flight risks to aircraft.

[0003] Icing weather includes icing with supercooled water droplets smaller than 50 microns (Appendix C to Part 25 of the Civil Aviation Regulations of China) and icing with supercooled large water droplets larger than 50 microns (Appendix 0 to the Civil Aircraft Airworthiness Management Regulations of the People's Republic of China). Traditional ice detectors can identify icing weather, but they cannot further distinguish between supercooled water droplets and supercooled large droplets.

[0004] Conventional aircraft anti-icing systems are designed based on icing weather conditions with a particle size of less than 50 microns. Therefore, when an aircraft enters an icing weather condition with supercooled large droplets exceeding 50 microns, the anti-icing capability is insufficient to cover this icing weather condition, and the aircraft may freeze rapidly and then stall and crash.

[0005] Currently, a feasible solution for supercooled large droplet icing weather is to immediately execute an escape maneuver once a detector detects the entry of supercooled large droplet icing weather. To this end, it is crucial to develop a detector that can accurately and reliably identify and distinguish supercooled large droplet icing weather.

[0006] Summary of the Invention

[0007] The present invention is made to solve the above-mentioned technical problems, and its purpose is to provide a supercooled large water droplet detector, more specifically a supercooled large water droplet detector with a (for example, spherical) detection structure, which can accurately and reliably identify and distinguish supercooled large water droplet freezing weather.

[0008] In order to achieve the above-mentioned purpose, the present invention provides a supercooled large water droplet detector, comprising a detector base and a detection structure, characterized in that the detection structure is used to detect supercooled water droplets in the airflow and to identify and distinguish from icing weather the icing weather in which the supercooled water droplets exceed a critical size of supercooled large water droplets. The detection structure comprises a three-layer structure, the outer layer is a uniformly arranged temperature sensor layer, the middle layer is an electric heating film layer, and the inner layer is a structural base. The electric heating film layer uniformly arranged in the middle layer of the detection structure provides heating energy through multiple electric heating circuits located at multiple different positions, so that the surface of the detection structure is free from external The temperature is kept uniform when affected by airflow and water droplets. The temperature sensor layer uniformly arranged on the outer layer of the electric heating film layer has multiple temperature sensors for real-time detection of surface temperature changes at the multiple different positions of the detection structure. A controller is provided in the base of the structure. The controller infers the impact range of the supercooled water droplets through the temperature changes at the multiple different positions caused by the supercooled water droplets impacting the detection structure, and determines whether the previously impacted supercooled water droplets are the supercooled large water droplets by judging whether the impact range exceeds the critical impact range when the supercooled water droplets of the critical size impact the detection structure.

[0009] According to the structure as described above, when supercooled water droplets of different sizes in the airflow hit the detection structure of the supercooled large water droplet detector, the position range of the temperature change of the detection structure caused by the supercooled water droplets is used to quantify the size of the supercooled water droplets, thereby solving the technical problem that traditional icing detectors can only be used to identify icing weather but cannot further distinguish whether it is supercooled water droplet icing weather or supercooled large water droplet icing weather. By accurately and reliably identifying and distinguishing supercooled large water droplet icing weather, safety incidents such as rapid freezing of the aircraft and subsequent stall and crash due to insufficient anti-icing capability can be prevented, thereby improving the safety and airworthiness of the aircraft.

[0010] In the present invention, the detection structure is preferably spherical. This is because when a sphere collides with the airflow in any direction and angle, the relative position of the airflow relative to the first stagnation point (critical impact range of supercooled water droplets of critical size) and the maximum stagnation point (maximum impact range of supercooled water droplets) of the detection structure (i.e., the maximum arc length of the impact area between the first and second areas) does not change. In addition, when supercooled water droplets impact the detection structure, supercooled water droplets below the critical size only impact the first area between the first stagnation points of the airflow, while supercooled water droplets exceeding the critical size impact the second area between the maximum stagnation points of the airflow at the same time as impacting the first area. In addition, considering that aircraft, especially civil aircraft, have maximum lift and pitch angles, it is impossible for the aircraft to rise vertically with its nose pointed 90 degrees upward, nor is it possible for the aircraft to fall vertically with its nose pointed 90 degrees downward. Therefore, as long as the relative position of the airflow relative to the first and maximum stagnation points of the detection structure does not change within the flight range between the aircraft's maximum lift and pitch angles, the detection structure is not limited to a strict spherical shape and can also be a substantially spherical shape with a spherical airflow impact area. At this time, it is desirable to form the portion connected to the duct (airflow non-impact region) into a streamlined shape suitable for allowing air to flow with low resistance.

[0011] Preferably, the supercooled large water droplet detector is installed at the nose position of the aircraft, and the supercooled large water droplet detector also has a curved pipe connecting the detector base with the detection structure. The detector base connected to one end of the pipe is installed inside the aircraft skin (not shown) and fixed to the fuselage structure. The pipe is bent so that the detection structure connected to the other end of the pipe is parallel to the airflow direction of the aircraft and faces the airflow.

[0012] According to the above-described structure, the curved pipe can minimize the influence of the pipe on the air flow field of the detection structure, thereby ensuring that supercooled water droplets in the air flow collide with the detection structure.

[0013] In addition, preferably, the multiple temperature sensors transmit the temperature detection values ​​or temperature change values ​​at the corresponding positions to the controller through temperature sensor cables respectively, and the multiple electric heating circuits are connected to the controller using energized cables. The controller is responsible for providing current to the multiple electric heating circuits of the electric heating film layer and collecting signals from the multiple temperature sensors of the temperature sensor layer and performing data processing.

[0014] Further preferably, the pipe is a hollow pipe, and the temperature sensor cable and the power cable are arranged inside the pipe.

[0015] According to the above-mentioned structure, by adopting a hollow structure, the temperature sensor connected between the detection structure and the detector base (controller installed inside) and the cables of the electric heating circuit (sensor cable, power cable) can be arranged inside the pipe, preventing the cables from being exposed to the outside and aging, thereby improving the service life and safety of the detector.

[0016] Preferably, each of the electric heating circuits corresponding to different positions in the electric heating film layer is arranged in a spiral shape or a U-shape, and the measurement position of the temperature sensor is uniformly arranged at the center of the U-shape or spiral of each of the electric heating circuits in the electric heating film layer.

[0017] According to the above configuration, the electric heating circuit using a spiral or U-shaped arrangement can provide uniform heating power at every position, improving temperature stability during use. In addition, by uniformly arranging the measurement position of the temperature sensor at the exact center of the U-shaped or spiral shape of the electric heating circuit, the measurement consistency of the outer temperature sensors can be ensured.

[0018] In addition, it is preferred that the structural base is made of a poor thermal conductor material.

[0019] According to the above configuration, the heat generated by the electric heating film layer in the middle layer can be mainly conducted toward the outer layer side of the detection structure.

[0020] Due to current technological limitations, in icing conditions, supercooled water droplets below a certain critical size (50 microns) can be prevented from freezing by the aircraft's anti-icing system, while supercooled large water droplets exceeding this critical size can only be immediately evaded. However, with future technological advancements, it is possible that in icing conditions where only an immediate evasion action can be performed, other actions, rather than just an immediate evasion action, can be employed for icing conditions with supercooled water droplets below another critical size. In this case, the other critical size can be considered as the critical size of the present invention to identify and distinguish areas where only an evasion action can be performed. Alternatively, both the 50 micron critical size and the other critical size can be considered as the critical sizes of the present invention to identify and distinguish a first area where a first action can be performed, a second area where a second action can be performed, and a third area where a third action (evasion action) can be performed. Thus, the icing conditions may include icing conditions with supercooled water droplets of multiple different critical sizes, and the supercooled large water droplet detector can detect the size range of supercooled water droplets impacting the detection structure to determine the current icing condition.

[0021] The size of the detection structure is 30 to 300 mm, and the size of the detection structure, the cross-sectional size of the temperature sensor, and the layout size of the electric heating circuit preferably include the following combinations: Combination 1, that is, the size of the detection structure is 50 mm, the cross-sectional size of the temperature sensor is 1 mm, and the layout size of the electric heating circuit is 3 mm; Combination 2, that is, the size of the detection structure is 100 mm, the cross-sectional size of the temperature sensor is 2 mm, and the layout size of the electric heating circuit is 4 mm; Combination 3, that is, the size of the detection structure is 150 mm, the cross-sectional size of the temperature sensor is 3 mm, and the layout size of the electric heating circuit is 5 mm; Combination 4, that is, the size of the detection structure is 200 mm, the cross-sectional size of the temperature sensor is 3 mm, and the layout size of the electric heating circuit is 6 mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG1 is a schematic structural diagram of a supercooled large water droplet detector for detecting (identifying and distinguishing) supercooled large water droplet icing weather according to an embodiment of the present invention.

[0023] FIG. 2 is a cross-sectional view of, for example, a spherical detection structure of the supercooled large water droplet detector shown in FIG. 1 .

[0024] FIG3 is a layout diagram of the electric heating circuit and the temperature sensor in a first form (spiral shape) in the spherical detection structure of the supercooled large water droplet detector of the present invention.

[0025] FIG4 is a layout diagram of the electric heating circuit and the temperature sensor in the second form (U-shaped) layout in the spherical detection structure of the supercooled large water droplet detector of the present invention.

[0026] (Explanation of Symbols)

[0027]

[0028] 100 Supercooled large water droplet detector;

[0029] 200 detector base;

[0030] 300 spherical detection structure;

[0031] 300A First Area

[0032] 300B Second Area

[0033] 310 temperature sensor layer;

[0034] 311 temperature sensor;

[0035] 312 temperature sensor cable;

[0036] 320 electric heating film layer;

[0037] 321 electric heating circuit;

[0038] 322 powered cables;

[0039] 330 spherical structure base;

[0040] 400 pipelines;

[0041] 500 controller. DETAILED DESCRIPTION

[0042] The structure of the supercooled large water droplet detector 100 of the present invention is described in detail below with reference to Figures 1 to 4 . Figure 1 is a schematic structural diagram of a supercooled large water droplet detector 100 for detecting (identifying and distinguishing) supercooled large water droplet icing weather according to one embodiment of the present invention, and Figure 2 is a cross-sectional view of the (e.g., spherical) detection structure 300 of the supercooled large water droplet detector 100 shown in Figure 1 . Furthermore, Figures 3 and 4 are layout diagrams of the electric heating circuit 321 and temperature sensor 311 in the detection structure 300 of the supercooled large water droplet detector of the present invention in two configurations: Figure 3 shows a spiral layout as a first configuration, and Figure 4 shows a U-shaped layout as a second configuration.

[0043] As shown in FIG1 , the supercooled large water droplet detector 100 of the present invention includes a detector base 200 , a detection structure 300 , and a pipe 400 connecting the detector base 200 and the detection structure 300 .

[0044] The detector base 200 is installed inside the aircraft skin (not shown) and connected to the aircraft body structure to provide support for the supercooled large water droplet detector 100 of the present invention. In addition, in the present invention, the controller 500 is arranged in the base 200.

[0045] The detection structure 300 is used to detect supercooled water droplets in the airflow and to identify and distinguish large supercooled water droplets exceeding 50 microns from icing weather. As shown in FIG2 , the detection structure 300 is, for example, spherical and comprises a three-layer structure: an outer layer comprising a uniformly arranged temperature sensor layer 310, a middle layer comprising a uniformly arranged electric heating film layer 320, and an inner layer comprising a (e.g., spherical) structural base 330. The supercooled water droplet detection function is achieved by uniformly arranging the middle layer's electric heating film structure 320 and the outer layer's temperature sensor 310 on the inner layer's structural base 330.

[0046] The temperature sensor layer 310 uniformly arranged on the outer layer of the electric heating film layer 320 has multiple temperature sensors 311 for real-time detection of surface temperature changes at multiple positions (different positions) of the detection structure 300, and transmits the temperature detection value or temperature change value to the controller 500 for analysis through the temperature sensor cable 312.

[0047] The electric heating film layer 320 uniformly arranged on the middle layer of the structural base 330 provides heating energy through multiple electric heating circuits 321 connected by energized cables 322, so that the surface of the detection structure 300 is maintained at a uniform temperature when there is no external airflow and water droplets. Here, it should be noted that the electric heating film layer 320 should maintain temperature stability during use and should have a certain adjustable temperature range, for example, 100 to 130 ° C. In order to provide uniform heating power, the layout of each electric heating circuit 321 corresponding to different positions in the electric heating film layer 320 can adopt a spiral layout as the first form shown in Figure 3 (i.e., each electric heating circuit 321 is arranged in a spiral shape) or a chevron layout as the second form shown in Figure 4 (i.e., each electric heating circuit 321 is arranged in a chevron shape). In addition, in order to ensure the measurement consistency of the temperature sensor 311 of the outer layer, the measurement position of the temperature sensor 311 is uniformly arranged at the center of the chevron or spiral shape of each electric heating circuit 321 of the electric heating film layer 320.

[0048] The inner structural base 330 is made of a poor thermal conductor material such as non-metal, so that the heat generated by the electric heating film layer 320 in the middle layer is mainly conducted to the outer layer side of the detection structure 300.

[0049] One end of the pipe 400 is connected to the detector base 200, and the other end is connected to the detection structure 300, and the pipe 400 is a hollow and curved pipe. By adopting a hollow structure, the temperature sensor 311 connected between the detection structure 300 and the detector base 200 (the controller 500 arranged therein) and the cables (sensor cable 312, power cable 322) of the electric heating circuit 321 can be arranged inside the pipe 400. In addition, through this curved design of the pipe, the detection structure 300 connected to the other end of the pipe 400 is basically parallel to the airflow direction of the aircraft and faces the airflow, minimizing the impact of the pipe 400 on the air flow field of the detection structure 300 to ensure that the supercooled water droplets in the airflow collide with the detection structure 300.

[0050] The controller 500 is responsible for providing current to the electric heating circuit 321 of the electric heating film layer 320 and collecting and processing signals from the temperature sensor 311 of the temperature sensor layer 310. The temperature sensor 311 used in this process should have high accuracy to accurately determine the temperature changes at multiple locations (different locations) caused by the impact of the supercooled water droplets, thereby inferring the impact range of the supercooled water droplets.

[0051] The supercooled large water droplet detector 100 of the present invention is installed at the nose position of the aircraft. When the aircraft is powered on, the supercooled large water droplet detector 100 starts to work, and the electric heating film layer 320 of the middle layer of the detection structure 300 is energized through the controller 500. Each electric heating circuit 321 is provided with the same voltage and current, so that the detection structure 300 is evenly heated and the temperature is maintained between 100 and 130°C.

[0052] When supercooled water droplets are present in the airflow, the supercooled water droplets will impact the surface of the detection structure 300. The impact limit range of supercooled water droplets larger than 50 microns (supercooled large water droplets) on the surface of the detection structure 300 is greater than the impact range of supercooled water droplets (ordinary water droplets) smaller than 50 microns. At the same time, the heat of the impacted area will be taken away by the impacted water droplets, resulting in a significant temperature difference between this area (impacted area) and the non-impacted area. The controller 500 analyzes the surface temperature data of the detection structure 300 to determine the impact range (impacted area) of the supercooled water droplets on the surface of the detection structure 300, and then compares the impact range (impacted area) with the impact range of supercooled large water droplets of 50 microns to determine whether the water droplets that previously impacted were supercooled water droplets larger than 50 microns (supercooled large water droplets), thereby identifying and distinguishing whether the air is in (or has entered) supercooled large water droplet freezing weather.

[0053] In Figure 1, supercooled water droplets (ordinary water droplets) below 50 microns will only collide with the first area 300A, while supercooled water droplets larger than 50 microns will collide with the second area 300B at the same time as collide with the first area 300A. That is, the critical line between the first area 300A and the second area 300B (that is, the maximum arc length of the first area 300A) is the first stagnation point when the supercooled water droplet of 50 microns collides with the detection structure 300 (or the critical collision range of the supercooled water droplet of critical size), and the maximum arc length of the second area 300B is the maximum stagnation point when the supercooled water droplet collides with the detection structure 300 (or the maximum collision range of the supercooled water droplet). At this time, no matter how large the supercooled water droplet is, it is impossible for it to collide with other areas of the detection structure 300 other than the first area 300A and the second area 300B. When the flight angle changes, the actual positions of the first area 300A and the second area 300B in the detection structure 300 will change, but the relative positions of the airflow relative to the first stagnation point (critical impact range of supercooled water droplets of critical size) and the maximum stagnation point (maximum impact range of supercooled water droplets) of the detection structure 300 (i.e., the maximum arc length of the impact area of ​​the first area 300A and the second area 300B) will not change. When passing through clouds, if the impact area of ​​the supercooled water droplets in flight increases and exceeds the first area 300A (i.e., the arc length of the impact area is greater than the maximum arc length of the first area 300A), it can be determined that the previously impacted water droplets are supercooled water droplets larger than 50 microns (supercooled large water droplets), and the current situation is (or has entered) supercooled large water droplet freezing weather. On the contrary, if the impact area of ​​the supercooled water droplets in flight does not exceed the first area 300A (i.e., the arc length of the impact area is less than the maximum arc length of the first area 300A), it is determined that the previously impacted water droplets are not supercooled large water droplets, and are not in (or have entered) supercooled large water droplet freezing weather.

[0054] Furthermore, the present invention utilizes, for example, a spherical detection structure 300 with a heating function, and based on aerodynamic principles, converts the detection of supercooled water droplet diameter (i.e., the determination of supercooled large water droplets) into the detection of temperature distribution. As the diameter of the spherical detection structure 300 increases, the area (i.e., the second area) where supercooled water droplets exceeding 50 microns (supercooled large water droplets) impact the spherical detection structure 300 becomes larger, as distinguished from supercooled water droplets below 50 microns (ordinary water droplets). Consequently, under the same detection requirements, there is no need for expensive, highly sensitive, small-sized temperature sensors. However, since the supercooled large water droplet detector 100 is used on aircraft, a compact structure and easy installation remain top priorities.

[0055] In the present invention, the size of the (spherical) detection structure 300 is not a fixed value, but the following two factors are mainly considered when determining the appropriate size:

[0056] (1) On the one hand, the larger the diameter of the detection structure 300, the more accurate and sensitive the temperature field distribution on the surface of the detection structure 300 will be when the temperature sensor 311 of the same size is measured. However, the larger the detection structure 300 (and the more accurate measurement of the temperature field distribution) will bring about the disadvantage of increased power consumption of the device.

[0057] (2) On the other hand, the smaller the diameter of the detection structure 300, the lower the measurement accuracy and sensitivity of the temperature field distribution on the surface of the detection structure 300 by the temperature sensor 311 of the same size. At the same time, the smaller the diameter of the detection structure 300, the smaller, more expensive and more sensitive temperature sensor 311 is required, and the layout of the electric heating circuit 321 is required to be more sophisticated.

[0058] In summary, taking various factors into consideration, the size of the preferred detection structure 300 of the present invention can be between 30 and 300 mm, and the combination of the size of the detection structure 300 and the cross-sectional size of the heating circuit and the temperature sensor can be exemplarily taken as shown in Table 1 below. However, those skilled in the art should know that the various dimensions of the present invention should not be limited to the size combinations shown in Table 1.

[0059] Table 1:

[0060] Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the present invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Therefore, modifications may be made without departing from the spirit or scope of the overall inventive concept as defined by the appended claims and their equivalents.

[0061] For example, in the present invention, the detection structure 300 is spherical for illustration. This is because the sphere collides with the airflow in any direction and angle. The relative position of the airflow relative to the first stagnation point (critical impact range of supercooled water droplets of critical size) and the maximum stagnation point (maximum impact range of supercooled water droplets) of the detection structure 300 (i.e., the maximum arc length of the impact area of ​​the first area 300A and the second area 300B) will not change. However, considering that aircraft, especially civil aircraft, have maximum lift and pitch angles, as long as the maximum lift and pitch angles of the aircraft are guaranteed, the maximum lift and pitch angles of the aircraft will not change. Within the flight range between the depression angles, the relative positions of the airflow relative to the first stagnation point (critical impact range of supercooled water droplets of critical size) and the maximum stagnation point (maximum impact range of supercooled water droplets) of the detection structure 300 (i.e., the maximum arc length of the impact area of ​​the first area and the second area) do not change. The detection structure 300 is not limited to a sphere in a strict sense, but can also be a substantially spherical shape in which the airflow impact area is spherical. In this case, it is preferred that the portion connected to the pipe 400 (the airflow non-impact area) is formed into a streamlined shape suitable for allowing air to flow through with low resistance.

[0062] In addition, in the present invention, 50 microns is used as the critical size of the supercooled water droplets to distinguish them from the supercooled large water droplets, but the present invention is not limited to this. It does not rule out that the critical size will be further divided from the perspective of airworthiness in the future, that is, it can also be any suitable value other than 50 microns.

[0063] Furthermore, under current technology, supercooled water droplets smaller than 50 microns can be prevented from freezing by the aircraft's anti-icing system, while supercooled large water droplets larger than 50 microns require an immediate escape maneuver. However, with future technological advancements, it is possible that in icing conditions smaller than a first size (e.g., 50 microns), the aircraft will employ a first maneuver (e.g., preventing icing through the aircraft's anti-icing system); in icing conditions larger than the first size but smaller than a second size, the aircraft will employ a second maneuver; and in icing conditions larger than the second size, the aircraft will employ a third maneuver (e.g., immediately executing an escape maneuver). In this case, a second size, different from the first size, can be used as the same critical point as in the aforementioned embodiment to identify and distinguish between first region 300A for anti-icing and second region 300B for escape. Alternatively, both the first and second sizes can be used as the same critical points as in the aforementioned embodiment to identify and distinguish between a first region for the first maneuver, a second region for the second maneuver, and a third region for the third maneuver.

Claims

1. A supercooled large water droplet detector, comprising a detector base and a detection structure, It is characterized in that The detection structure is used to detect supercooled water droplets in the airflow and to identify and distinguish icing weather in which the supercooled water droplets exceed a critical size from icing weather. The detection structure includes a three-layer structure, the outer layer is a uniformly arranged temperature sensor layer, the middle layer is an electric heating film layer, and the inner layer is a structural base. The electric heating film layer uniformly arranged on the middle layer of the detection structure provides heating energy through multiple electric heating circuits located at multiple different positions, so that the surface of the detection structure is kept at a uniform temperature when there is no influence of external airflow and water droplets. The temperature sensor layer uniformly arranged on the outer layer of the electric heating film layer has a plurality of temperature sensors for real-time detection of surface temperature changes at the plurality of different positions of the detection structure. A controller is provided in the structural base, and the controller infers the impact range of the supercooled water droplet through the temperature changes at the multiple different positions caused by the supercooled water droplet impacting the detection structure, and determines whether the supercooled water droplet that previously impacted is the supercooled large water droplet by judging whether the impact range exceeds the critical impact range when the supercooled water droplet of the critical size impacts the detection structure.

2. The supercooled large water drop detector according to claim 1, characterized in that: The detection structure is spherical or substantially spherical.

3. The supercooled large water droplet detector according to claim 2, characterized in that: The critical impact range when the supercooled water droplet of the critical size impacts the detection structure is the first stagnation point of the airflow, The maximum impact range of the supercooled water droplet when it impacts the detection structure is the maximum stagnation point of the airflow. When the airflow collides with the detection structure in any direction and angle within the flight range between the maximum lift angle and the maximum pitch angle of the aircraft, the first stagnation point of the airflow and the maximum stagnation point of the airflow are The relative position of the dead points does not change.

4. The supercooled large water drop detector according to claim 3, characterized in that: When supercooled water droplets hit the detection structure, supercooled water droplets below the critical size only hit the first area between the first stagnation points of the airflow, while supercooled large water droplets exceeding the critical size hit the second area between the maximum stagnation points of the airflow while hitting the first area.

5. The supercooled large water droplet detector according to claim 3, characterized in that: The supercooled large water droplet detector is installed at the nose of the aircraft. The supercooled large water drop detector also has a curved pipe connecting the detector base with the detection structure. The detector base connected to one end of the pipe is installed inside the aircraft skin (not shown) and fixed to the fuselage structure. The duct is bent so that the detection structure connected to the other end of the duct faces the airflow in parallel with the airflow direction of the aircraft.

6. The supercooled large water droplet detector according to claim 5, characterized in that: The portion connected to the duct, ie, the airflow non-impacting area, is formed into a streamline shape suitable for allowing air to flow through with low resistance.

7. The supercooled large water droplet detector according to claim 5, characterized in that: The plurality of temperature sensors transmit the temperature detection values ​​or temperature change values ​​at corresponding positions to the controller through temperature sensor cables respectively. A plurality of electric heating circuits are connected to the controller using powered cables. The controller is responsible for providing current to the multiple electric heating circuits of the electric heating film layer and collecting signals from the multiple temperature sensors of the temperature sensor layer and performing data processing.

8. The supercooled large water droplet detector according to claim 7, characterized in that: The pipe is a hollow pipe. The temperature sensor cable and the power cable are arranged inside the pipe.

9. The supercooled large water drop detector according to any one of claims 1 to 8, characterized in that: Each of the electric heating loops corresponding to different positions in the electric heating film layer is arranged in a spiral shape or in a U-shaped shape. The measuring position of the temperature sensor is uniformly arranged at the exact center of the U-shaped or spiral-shaped electric heating loop of each electric heating film layer.

10. The supercooled large water drop detector according to any one of claims 1 to 8, characterized in that: The structural base is made of a poor thermal conductor material.

11. The supercooled large water drop detector according to any one of claims 1 to 8, characterized in that: The icing weather has a plurality of supercooled water droplets of different critical sizes. The supercooled large water droplet detector can detect the size range of the supercooled water droplets that hit the detection structure to determine the current icing weather.

12. The supercooled large water drop detector according to any one of claims 1 to 8, characterized in that: The size of the detection structure is 30 to 300 mm. The size of the detection structure, the cross-sectional size of the temperature sensor, and the layout size of the electric heating circuit include the following combinations: Combination 1, that is, the size of the detection structure is 50 mm, the cross-sectional size of the temperature sensor is 1 mm, and the layout size of the electric heating loop is 3 mm; Combination 2, that is, the size of the detection structure is 100 mm, and the cross-sectional size of the temperature sensor is The size of the electric heating circuit is 2 mm, and the layout size of the electric heating circuit is 4 mm; Combination 3, that is, the size of the detection structure is 150 mm, the cross-sectional size of the temperature sensor is 3 mm, and the layout size of the electric heating loop is 5 mm; Combination 4, that is, the size of the detection structure is 200 mm, the cross-sectional size of the temperature sensor is 3 mm, and the layout size of the electric heating loop is 6 mm.

Images