Method for obtaining wave water surface sliding splash expression atlas of water surface aircraft

Abstract

The application provides a method for obtaining a wave surface sliding splash expression atlas of a water surface aircraft, comprising: obtaining splash expression atlas parameters; obtaining model test parameters; performing a model splash test according to the model test parameters to obtain a splash video; determining a splash intensity according to the splash video; and drawing a splash expression atlas according to the splash intensity; a set of water surface aircraft weight, wave significant wave height and splash action position value combinations corresponds to one splash expression atlas, the horizontal axis of the splash expression atlas is divided into multiple sections according to the flight speed of the water surface aircraft, the vertical axis is divided into multiple sections according to the wavelength of the wave, forming a rectangular block diagram, and the color of each rectangular block is determined according to the corresponding splash intensity. The splash expression atlas provided by the application is complete and intuitive.

Description

Technical Field

[0001] This invention belongs to the field of hydrodynamic performance technology of water surface aircraft, specifically relating to a method for obtaining wave surface gliding and splash expression maps of water surface aircraft. Background Technology

[0002] Spray is the stream or spray of water ejected from the point of contact between the fuselage and the water surface of a water-based aircraft during gliding on the water surface. Figure 1 As shown, after being ejected from the hull, the water jets generally move in three-dimensional space relative to the aircraft along the sides and rear. During this movement, the water jets may impact aircraft structural components such as wings, engines, and flaps, thus adversely affecting the safe operation of the aircraft. The greater the volume of water jets and the higher the speed of movement, the more severe the impact. Timely detection or prediction of the impact of water jets on aircraft is crucial for safe flight.

[0003] Currently, the main methods for testing and analyzing the splash characteristics of surface aircraft include invention patents such as "A Test Method for Splash of a Single-Hull Model of a Surface Aircraft in a Water Tank" (ZL201310575739.0) and "A Test Method for Splash of a Full-Screen Dynamic Model of a Surface Aircraft in a Water Tank" (ZL201410289978.4), academic papers such as "Research on the Analysis Method of Splash Peak Points of Amphibious Aircraft Models" (Aeronautical Computing Technology, 2015, Vol45, No.6) and "Comparative Experimental Study on the Influence of Suppression Groove Width on the Splash Performance of Amphibious Aircraft" (Aeronautical Science and Technology, 2015, Vol26, No.1), which propose splash model testing methods and splash expression methods (such as...). Figure 2 and Figure 3 (As shown). Among them, Figure 2 The splash envelope in the image is drawn based on the highest and farthest splash positions captured by the test video, which can reflect the range of splash action under all working conditions; Figure 3 The splash V-shaped diagram can express the impact area of ​​splashes under different weights and speeds on still water and wave surfaces.

[0004] Existing methods of representing splash still suffer from incomplete information and lack of intuitiveness. Summary of the Invention

[0005] This invention provides a method for obtaining a splash representation map of a water surface vehicle gliding on a wave surface, and the generated splash representation map information is complete and intuitive.

[0006] This invention provides a method for obtaining wave surface gliding and splash representation maps of a water surface vehicle, comprising:

[0007] Obtain the set of possible flight speeds for the water surface vehicle and the set of possible wavelengths for the waves;

[0008] Based on the weight of the watercraft and the meaningful wave height H of the preset water area, 1 / 3 The parameters for the splash model test are obtained by taking the set of values ​​for flight speed and the set of values ​​for wavelength. The splash model test parameters include: model test weight, model test wave height, and the set of values ​​for flight speed and wavelength corresponding to the set of values ​​for model test wavelength.

[0009] Based on the splash model test parameters, a splash test was conducted to obtain splash videos;

[0010] Based on the splash video, determine the splash intensity at each splash location under different combinations of splash model test parameters;

[0011] Based on the splash intensity at each splash location under different combinations of splash model test parameters, a splash representation map is drawn at the splash location.

[0012] In this model, a set of values ​​for the weight of a water surface vehicle, the meaningful wave height of a wave, and the location of the splash action corresponds to a splash representation map. The horizontal axis of the splash representation map is divided into multiple segments according to the flight speed of the water surface vehicle, and the vertical axis is divided into multiple segments according to the wavelength of the wave, forming a rectangular block map. The color of each rectangular block is determined according to the corresponding splash intensity.

[0013] Optionally, obtain the set of possible values ​​for the flight speed of the water surface vehicle, including:

[0014] Within 20% to 90% of the take-off speed Vto of the water-based aircraft, a series of speed values ​​are taken at preset speed intervals as elements in the set of flight speed values;

[0015] Among them, the smallest element in the set of flight speed parameter values ​​is the nearest ten number to 20%Vto, and is not less than 20km / h, and the number of elements in the set of flight speed values ​​is not less than 5.

[0016] Optionally, obtain the set of possible wavelength values ​​for the wave, including:

[0017] The meaningful wave height H of the preset water area for a surface-to-water aircraft is K1 times that of the target area. 1 / 3 The value is the lower limit, and a series of wavelength values ​​are taken at preset wavelength intervals as elements in the set of wavelength values ​​for the wave;

[0018] Among them, the minimum wavelength in the set of wave wavelength values ​​is less than the length of the aircraft fuselage, the maximum wavelength is greater than K2 times the length of the aircraft fuselage, and the number of elements in the set of wave wavelength values ​​is no less than 5; K1 and K2 are positive numbers.

[0019] Optionally, based on the weight of the surface aircraft and the wave height H of the preset water area, the specific wave height H can be determined. 1 / 3 The set of flight speed values ​​and the set of wavelength values ​​are used to obtain the parameters for the splash model test, including:

[0020] Based on the set of values ​​for the weight and speed of the surface aircraft, the set of values ​​for the model test weight and speed is determined according to the Froude number similarity principle.

[0021] Optionally, based on the weight of the surface aircraft and the wave height H of the preset water area, the specific wave height H can be determined. 1 / 3 The set of flight speed values ​​and the set of wavelength values ​​are used to obtain the parameters for the splash model test, including:

[0022] According to the preset water wave height H of the water surface aircraft, 1 / 3 Using formula Determine the wave height H in the model test m ;

[0023] Where λ is the scale.

[0024] Optionally, based on the weight of the surface aircraft and the wave height H of the preset water area, the specific wave height H can be determined. 1 / 3 The set of flight speed values ​​and the set of wavelength values ​​are used to obtain the parameters for the splash model test, including:

[0025] Based on the set of wavelength values, formula L is used. m =λL, to obtain the set of wavelength values ​​for the model experiment; where L is the wavelength, L m λ is the wavelength of the model test, and λ is the scale.

[0026] Optionally, the splashing locations include the propeller and flap locations.

[0027] Optionally, splash intensity includes: no splash, slight splash, strong splash, and severe splash;

[0028] No splash means that there is no visible spray or drop of water entering the propeller disk or impacting the flaps;

[0029] Slight splashing indicates that water droplets or sprays have entered the propeller disk or impacted the flaps;

[0030] Stronger splashing indicates that there is a jet of water or a column of water entering the propeller disk or impacting the flaps;

[0031] Severe splashing indicates that a large amount of splashed water or water jets have entered the propeller disk or impacted the flaps.

[0032] Optionally, in the splash representation map, the rectangles corresponding to severe splashes are represented in red, the rectangles corresponding to moderate splashes are represented in yellow, the rectangles corresponding to slight splashes are represented in gray, and the rectangles corresponding to no splashes are represented in green.

[0033] This invention provides a method for obtaining a splash representation map of a surface-to-water vehicle (STOVL) during wave gliding. The method includes: acquiring splash representation map parameters; acquiring model test parameters; conducting a model splash test based on the model test parameters to obtain a splash video; determining the splash intensity based on the splash video; and drawing a splash representation map based on the splash intensity. A set of combinations of STOVL weight, wave height, and splash location values ​​corresponds to a splash representation map. The horizontal axis of the splash representation map is divided into multiple segments based on the STOVL flight speed, and the vertical axis is divided into multiple segments based on the wave wavelength, forming a rectangular block diagram. The color of each rectangular block is determined according to the corresponding splash intensity. The splash representation map obtained using the method provided by this invention provides complete information (including the vehicle's weight, speed, wave height, and wavelength) and is intuitive. In practical use, pilots can quickly determine the extent of the splash's impact on the vehicle based on the vehicle's state (weight, speed) and wave conditions (wave height, wavelength), improving the practicality of the splash representation map. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of a splashing water stream.

[0036] Figure 2 A schematic diagram of the splash envelope;

[0037] Figure 3 This is a schematic diagram of the V-shaped pattern of the splash.

[0038] Figure 4 A flowchart illustrating the method for obtaining wave surface gliding and splash representation maps of a water surface vehicle provided by the present invention;

[0039] Figure 5 This is a diagram illustrating a minor splash.

[0040] Figure 6 This is a schematic diagram of a strong splash.

[0041] Figure 7 This is a diagram illustrating severe splashing.

[0042] Figure 8 This is a schematic diagram of the sputtering pattern. Detailed Implementation

[0043] The method for obtaining wave surface gliding and splash representation maps of water surface vehicles provided by the present invention will be explained below with reference to the accompanying drawings.

[0044] This invention considers that the severity of splashing is affected by various factors such as aircraft weight, speed, and water surface conditions. Generally, in calm water, heavier aircraft have a greater draft, making splashing more likely to affect components such as wings, engines, and flaps. Speed ​​primarily affects the location and energy of splashing. At lower speeds, the fuselage waterline is positioned further forward, primarily affecting the engines and wings. At higher speeds, the waterline shifts aft, also shifting the splashing location, primarily affecting components like flaps. At even higher speeds, the splashing location is further aft, acting entirely behind the flaps and thus not affecting the aircraft's structural components. In wavy water, the patterns of splash location and severity are more complex than in calm water, related to the aircraft's weight, constant speed, and attitude response. Therefore, existing splash diagrams do not accurately reflect the specific conditions of wavy water, resulting in incomplete and unintuitive information.

[0045] This invention addresses the problem that splash envelopes and splash V-shaped diagrams do not express specific information about water surface wave conditions (such as wave height and wavelength), and that pilots cannot intuitively and conveniently determine the impact area and degree of splashing under current conditions based on the aircraft's speed and water surface conditions during takeoff and landing on water. It proposes a new wave-water surface splash representation map and a method for obtaining this splash representation map. This splash representation map expresses complete information (including aircraft weight, speed, wave height, and wavelength) and is intuitive. In practical use, pilots can quickly determine the extent of the splashing's impact on the aircraft based on the aircraft's status (weight, speed) and wave conditions (wave height, wavelength), thus improving the practicality of the splash representation map. The specific method for obtaining this splash representation map is as follows: Figure 4 As shown, it can specifically include:

[0046] (1) Determine the parameters of the sputtering expression map

[0047] Specifically, obtain the set of values ​​for the flight speed of the water surface vehicle and the set of values ​​for the wavelength of the waves.

[0048] The method for determining the speed parameters is as follows: within the range of 20% to 90% of the aircraft's takeoff speed Vto, a series of speed values ​​are taken at intervals of 10 km / h (preset speed intervals). The first speed value V1 is a multiple of ten near 20% of Vto, and is generally not less than 20 km / h. Then the speed parameters (not less than 5) can be expressed as: V1, V1+10 km / h, V1+20 km / h, etc.

[0049] For example, when the aircraft's takeoff speed Vto is 100 km / h, V1 is 20 km / h. The set of flight speed values ​​can include 20 km / h, 30 km / h, 40 km / h, 50 km / h, and 60 km / h; it can also be understood that it can include 20 km / h, 30 km / h, 50 km / h, 60 km / h, 80 km / h, 90 km / h, etc.

[0050] The method for determining the wavelength parameter is as follows: K1 times the significant wave height H. 1 / 3 The value is the lower limit. A series of wavelength values ​​are taken at intervals of 10m (preset wavelength). The minimum wavelength L1 must be less than 1 times the length of the aircraft fuselage, and the maximum wavelength must be greater than K2 times the length of the aircraft fuselage. The wavelength parameters (not less than 5) can be represented as L1, L1+10m, L1+20m, etc.

[0051] For example, K1 can be 7 and K2 can be 4.

[0052] (2) Determine the parameters of the model test

[0053] For the aircraft weight W and velocity V in the spectrum parameters, the corresponding weights Wm and Vm for the model test are determined according to the Froude number similarity principle.

[0054] Regarding the spectral parameter wave height H 1 / 3 The wavelength L and the wave height H corresponding to the model test are determined according to the following relationship. m Wavelength L corresponding to the model experiment m .

[0055] The method for converting wave height in the model experiment is as follows:

[0056]

[0057] The wavelength conversion method for model experiments is as follows:

[0058] L m =λL;

[0059] In the formula, λ is the scaling factor, which is the linear ratio between the experimental model and the full-size aircraft.

[0060] (3) Conduct scaled-down model splash tests

[0061] For example, a scaled-down model test can be conducted according to the test apparatus and method in "A Test Method for a Full-Scale Dynamic Model of a Water Surface Aircraft Spraying" (ZL201410289978.4). The video recorders on the side, front, and rear of the test model are high-definition cameras, which focus on the propeller and flap positions, respectively, to record the spray from the propeller and flap positions during the test model's uniform motion at a speed of Vm.

[0062] (4) Judgment of the degree of splashing effect

[0063] Using the video obtained from the high-definition camera, the degree of splashing in each state was judged according to the following criteria, and the judgment results were recorded in Table 1 below.

[0064] a) No splashing: No visible water jets or splashes enter the propeller disk or impact the flaps;

[0065] b) Minor splashing: Water droplets or sprays enter the propeller disk or impact the flaps. See typical examples. Figure 5 As shown;

[0066] c) Stronger splash: There is a spray of water or a jet of water entering the propeller disk surface, or impacting the flaps.

[0067] See typical examples Figure 6 As shown;

[0068] d) Severe splashing: A large amount of splash water or jets enters the propeller disk surface or impacts the flaps. See typical examples. Figure 7 As shown.

[0069] Table 1 Record of the degree of splashing effect

[0070]

[0071] (5) Draw a splash representation map

[0072] Based on the splash intensity records obtained from model tests, a splash pattern of the aircraft was plotted. The table was created with the aircraft velocity Vm on the horizontal axis and wavelength Lm on the vertical axis, using different colors to represent different splash intensities: severe splashing was represented by red, strong splashing by yellow, slight splashing by gray, and no splashing by green. A schematic diagram of the splash pattern under typical conditions is shown below. Figure 8 As shown.

[0073] For example, the present invention takes into account that the weight of the aircraft remains basically constant during actual flight and that the wave height changes slowly. It provides a splash expression map corresponding to different combinations of values ​​for the weight of the water surface aircraft, the wave height, and the splash action location. This allows the pilot to have sufficient time to switch splash expression maps during flight, thereby improving the practicality of the splash expression map.

[0074] The method provided by this invention yields, for example, Figure 8 The sputtering expression spectrum, and Figure 3 Compared to the V-shaped splash diagram shown, this one provides more comprehensive information, using different colors to represent different degrees of splash effect, making it more intuitive and eye-catching. In actual use, pilots can obtain information about the wave height and wavelength of the sea surface through visual observation (or other measurement methods), and combine this with the current speed displayed by the aircraft to quickly determine the degree of splash effect on the propeller and flaps under the current conditions, making more advantageous decisions.

Claims

1. A method for obtaining a wave surface gliding and splash representation map of a water surface vehicle, characterized in that, include: Obtain the set of possible flight speeds for the water surface vehicle and the set of possible wavelengths for the waves; According to the weight of the water surface aircraft, the significant wave height H of the preset water area of the water surface aircraft, a value set of flight speeds and a value set of wavelengths, a splash model test parameter is acquired 1 / 3 The splash model test parameter includes a model test weight, a model test wave height, a model test speed value set corresponding to the value set of flight speeds, and a model test wavelength value set corresponding to the value set of wavelengths. Based on the splash model test parameters, a splash test was conducted to obtain splash videos; Based on the splash video, determine the splash intensity at each splash location under different combinations of splash model test parameters; Based on the splash intensity at each splash location under different combinations of splash model test parameters, a splash representation map is drawn at the splash location. Among them, a set of values ​​for the weight of the water surface vehicle, the meaningful wave height of the wave, and the location of the splash action corresponds to a splash expression map. The horizontal axis of the splash expression map is divided into multiple segments according to the flight speed of the water surface vehicle, and the vertical axis is divided into multiple segments according to the wavelength of the wave, forming a rectangular block map. The color of each rectangular block is determined according to the corresponding splash intensity. Based on the weight of the watercraft and the meaningful wave height H of the preset water area, 1 / 3 The set of flight speed values ​​and the set of wavelength values ​​are used to obtain the parameters for the splash model test, including: According to the preset water wave height H of the water surface aircraft, 1 / 3 Using formula Determine the wave height of the model test H m ; Where λ is the scale.

2. The method according to claim 1, characterized in that, Obtain the set of possible flight speed values ​​for the water surface vehicle, including: Within 20% to 90% of the take-off speed Vto of the water-based aircraft, a series of speed values ​​are taken at preset speed intervals as elements in the set of flight speed values; Among them, the smallest element in the set of flight speed parameter values ​​is the nearest ten number to 20%Vto, and is not less than 20km / h, and the number of elements in the set of flight speed values ​​is not less than 5.

3. The method according to claim 1, characterized in that, Obtain the set of possible wavelength values ​​for the wave, including: The meaningful wave height H of the preset water area for a surface-to-water aircraft is K1 times that of the target area. 1 / 3 The value is the lower limit, and a series of wavelength values ​​are taken at preset wavelength intervals as elements in the set of wavelength values ​​for the wave; Among them, the minimum wavelength in the set of wave wavelength values ​​is less than the length of the aircraft fuselage, the maximum wavelength is greater than K2 times the length of the aircraft fuselage, and the number of elements in the set of wave wavelength values ​​is no less than 5; K1 and K2 are positive numbers.

4. The method according to claim 1, characterized in that, Based on the weight of the watercraft and the meaningful wave height H of the preset water area, 1 / 3 The set of flight speed values ​​and the set of wavelength values ​​are used to obtain the parameters for the splash model test, including: Based on the set of values ​​for the weight and speed of the surface aircraft, the set of values ​​for the model test weight and speed is determined according to the Froude number similarity principle.

5. The method according to claim 1, characterized in that, Based on the weight of the watercraft and the meaningful wave height H of the preset water area, 1 / 3 The set of flight speed values ​​and the set of wavelength values ​​are used to obtain the parameters for the splash model test, including: Based on the set of wavelength values, the formula is used. L m =λL, to obtain the set of wavelength values ​​for the model experiment; where L is the wavelength. L m λ is the wavelength of the model test, and λ is the scale.

6. The method according to claim 1, characterized in that, The splashing points include the propeller and flap locations.

7. The method according to claim 1, characterized in that, Splash intensity includes: no splash, slight splash, strong splash, and severe splash; No splash means that there is no visible spray or drop of water entering the propeller disk or impacting the flaps; Slight splashing indicates that water droplets or sprays have entered the propeller disk or impacted the flaps; Stronger splashing indicates that there is a jet of water or a column of water entering the propeller disk or impacting the flaps; Severe splashing indicates that a large amount of splashed water or water jets have entered the propeller disk or impacted the flaps.

8. The method according to claim 7, characterized in that, In the splash representation map, the rectangles corresponding to severe splashes are represented in red, those corresponding to moderate splashes are represented in yellow, those corresponding to slight splashes are represented in gray, and those corresponding to no splashes are represented in green.

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