A simulation method for detecting helicopter-dropped chaff clouds using a missile fuze

Abstract

The present invention discloses a method for simulating the detection of helicopter-dropped chaff clouds by missile fuzes. The method includes establishing a single-rotor blade tip vortex wake model; calculating the induced velocity field at any point in the helicopter wake; performing a visual simulation of the helicopter wake field using line segments and arrows based on the OpenGL open graphics library; establishing a motion model of a single chaff strip in the helicopter wake; and generalizing the single chaff strip motion model to obtain a model for the overall diffusion motion of the chaff cloud in the helicopter wake; performing a visual simulation of the dynamic diffusion of tens of millions of chaff clouds based on a particle system; establishing a hollow cone missile fuze detection field, determining the visibility of chaff particles within the detection field based on the overall diffusion motion model of the chaff cloud, and performing a detection simulation of the helicopter-dropped chaff cloud by the missile fuze based on the chaff cloud visualization simulation and the chaff particle visibility determination. The present invention closely resembles real-world conditions and has high accuracy.

Description

Technical Field

[0001] The invention relates to a fuze anti-passive interference simulation technology, in particular to a chaff cloud detection simulation method for a missile fuze under the action of a helicopter wake. Background Art

[0002] Chaff jamming is the longest-standing and most widely used passive jamming method. Chaff jammers are simple to manufacture and inexpensive. Within a combat zone, the aerial motion characteristics of a chaff cloud are affected not only by the atmospheric environment but also by the wake of dispensing platforms such as helicopters. The dynamic chaff cloud created by helicopter-launched chaff flares can effectively interfere with the radio fuzes of air defense missiles and air-to-air missiles, causing them to detonate prematurely or prevent detonation, significantly weakening the performance of missile weapon systems. Therefore, through simulation research on missile fuze detection of helicopter-dropped chaff clouds, we can deeply analyze the fuze signal processing process and explore methods and technical approaches to improve the fuze's ability to resist chaff jamming.

[0003] Existing research primarily focuses on modeling the dynamics of helicopter rotor wakes, often at a theoretical level. Visual simulation of the wake field has not been conducted and applied to the modeling and visualization of moving chaff clouds. Furthermore, these studies often simplify moving chaff clouds into standard geometric shapes, such as spheres and ellipsoids, resulting in limited model accuracy and reliability. Given the current operational environment, the use of helicopters to drop chaff bombs for jamming is common, so accurate modeling and detection simulation of moving chaff clouds under the influence of helicopter rotor wakes is essential.

[0004] In summary, the problems existing in the existing technology are: lack of visual simulation of helicopter wake field, and the simplified methods and models used in the modeling and detection simulation research of moving chaff cloud under the action of missile fuze on helicopter rotor wake are poor in accuracy. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for simulating the detection of a helicopter-dropped chaff cloud by a missile fuze, which is close to the actual situation and has good accuracy.

[0006] The technical solution for achieving the purpose of the present invention is: a method for simulating the detection of a helicopter-dropped chaff cloud by a missile fuze, comprising the following steps:

[0007] (10) Helicopter wake model: Based on the free wake model, a helicopter single rotor blade tip vortex wake model is established;

[0008] (20) Calculation of helicopter wake induced velocity: Based on the single rotor tip vortex wake model, calculate the induced velocity field at any point in the helicopter wake field;

[0009] (30) Visual simulation of helicopter wake field: Based on the single rotor blade tip vortex wake model and wake induced velocity, the visual simulation of helicopter wake field is completed using line segments and arrows based on the OpenGL open graphics library;

[0010] (40) Chaff cloud motion modeling: Establish a single chaff motion model under the force of air, and combine it with the wake induced velocity to obtain a single chaff motion model under the helicopter wake. The single chaff motion model is generalized to obtain the overall diffusion motion model of the chaff cloud under the helicopter wake.

[0011] (50) Visual simulation of chaff cloud: Based on the overall diffusion motion model of chaff cloud under the helicopter wake, a visualization simulation of the dynamic diffusion of chaff cloud with tens of millions of particles is completed based on the particle system;

[0012] (60) Simulation of missile fuze detection of chaff cloud: A hollow cone missile fuze detection field is established, and the visibility of chaff particles in the detection field is determined based on the overall diffusion motion model of the chaff cloud. Based on the chaff cloud visualization simulation and chaff particle visibility judgment, the missile fuze is simulated to detect the chaff cloud dropped by the helicopter.

[0013] Furthermore, the (10) helicopter wake model is modeled, the steps comprising:

[0014] Vortex line control equation To control, is the position vector of the vortex line positioning point in the flow field, ψ is the blade azimuth angle, ζ is the wake life angle, is the velocity of the positioning point, which is the resultant velocity of the free stream velocity and the vortex line node induced velocity, expressed as: is the wake velocity at infinity;

[0015] According to the relationship between rotor rotation: ψ=ζ=Ωt, Ω is the rotor speed, t is time, it can be deduced that:

[0016]

[0017] Therefore, the wake model of the tip vortex is:

[0018]

[0019] Positioning points for attached vortices, near wakes, and far wakes The resultant velocity of the induced velocity.

[0020] Furthermore, the (20) helicopter wake induced speed calculation step includes:

[0021] (21) Calculate the induced velocity of the rotor wake at the spatial point M: According to the single rotor tip vortex wake model, the wake model is discretized into a linear vortex element. The coordinates of the two end points of the linear vortex element are L1(x1, y1, z1) and L2(x2, y2, z2), respectively. Calculate the vector The vector coordinate calculation expression is:

[0022]

[0023] The expression of the induced velocity generated by the linear vortex element on the spatial point M is obtained as follows:

[0024]

[0025] in, is the induced velocity vector, Γ is the linear vortex element circulation, h is the distance from point M to the linear vortex element,

[0026]

[0027]

[0028] is the direction vector,

[0029]

[0030] (22) Rotor wake vortex core correction: The vortex core is corrected according to the following formula:

[0031]

[0032] where δ is the turbulent viscosity coefficient, v is the kinematic viscosity coefficient, and ζ 0 is the initial value of the wake life angle,

[0033] The corrected induced velocity calculation formula is:

[0034] r c is the vortex core radius.

[0035] Furthermore, the (30) helicopter wake field visualization simulation comprises the following steps:

[0036] According to the obtained helicopter wake model and helicopter wake induced velocity, the motion state of the particles in the helicopter wake field is obtained based on C++ programming. As the motion state is updated, the motion trajectories of some particles in the wake field are drawn with line segments based on the OpenGL open graphics library, and the motion directions of some particles in the wake field are drawn with arrows, thus obtaining a visual simulation model of the helicopter wake field.

[0037] Furthermore, the (40) foil cloud motion modeling step includes:

[0038] (41) Solution of helicopter wake wind force: Based on the obtained single rotor blade tip vortex wake model and induced velocity, it is converted into the wake wind force F acting on the foil strip through the following formula: wl ,

[0039] F wl =0.5ρv 2 S,

[0040] ρ is the air density, S = d × l / 4, d is the foil diameter, l is the foil length, and v is the induced velocity;

[0041] (42) Establish a force model for a single foil strip: When a single foil strip moves in the air, it is subjected to a vertical downward gravity G and an upward buoyancy F. fs , and the movement speed V cs Opposite air resistance F cs 、Wake wind force F wl , where the gravity acting on a single foil strip is:

[0042] G=mg,

[0043] m is the mass of a single foil strip, g is the acceleration due to gravity,

[0044] Buoyancy F fs =ρgV,

[0045] V is the volume of the foil strip. When the foil strip moves at a speed lower than 100 m / s, the air resistance it encounters is:

[0046] F cs =C D ρSV cs ,

[0047] C D is the drag coefficient. When the foil moves at a speed higher than 100 m / s, the air resistance it encounters is:

[0048]

[0049] (43) Establish a single chaff motion model: the velocity V0 of the chaff bomb when it is thrown out of the aircraft is the initial velocity V of the chaff bomb c With the aircraft speed V f The synthesis formula is:

[0050]

[0051] Where θ c is the installation angle of the chaff jet dispenser on the aircraft;

[0052] According to the force model of a single foil strip and the initial velocity of the foil strip, the components of the foil strip velocity on the three axes at any time are obtained:

[0053]

[0054] The sign function is the sign function, V cs X, V cs Y, V cs Z is the component of the motion velocity on the three axes, F cs X, F cs Y, F cs Z is the component of air resistance on the three axes, F wlX 、F wlY 、F wlZ is the component of the wake wind force on the three axes, V CS0X 、V CS0Y 、V CS0Z are the components of the initial velocity of the foil strip on the three axes, and then the displacement components of a single foil strip on the three axes at any time are calculated according to the above formula, thereby obtaining the position of the foil strip at any time;

[0055] (44) Foil cloud motion modeling: Based on the single foil motion model, the foil cloud motion model is obtained by superimposing and generalizing the single foil motion vector.

[0056] Furthermore, the (50) foil cloud visualization simulation comprises the following steps:

[0057] (51) Foil strip particle modeling: Gray particles are used to replace cylindrical foil strips for visual simulation in OpenGL. At the same time, a structure is constructed based on the C++ language to store foil strip related information. The foil strip particle structure stores the key information required to calculate the foil strip motion state, including the motion information of each foil strip itself, including speed and azimuth, and the foil strip's own property information, including mass, length, and survival time. It also contains some information about the foil strip cloud where the foil strip is located, including the particle spacing in the foil strip cloud, the foil strip cloud radius, and the volume;

[0058] (52) Visual simulation of foil cloud: After the foil particles are initialized, their activation state is determined. The activated foil particles calculate their force state and position information, and continuously update the relevant information as the simulation time progresses. The inactivated particles maintain their original state. Based on the foil position, color, transparency and other related properties stored in the foil particle structure, the visual simulation of tens of millions of foil particles is completed based on the OpenGL open graphics library.

[0059] Furthermore, the (50) missile fuze simulating chaff cloud detection comprises the following steps:

[0060] (61) Missile fuze detection field modeling: Based on the missile fuze action range and beam thickness, a hollow cone missile fuze detection field is established;

[0061] (62) Chaff particle visibility judgment: The following formula is used to judge whether all chaff particles under the influence of helicopter wake are within the missile fuze detection field:

[0062] g(θ)·r>R,

[0063] Where g(θ) represents the normalized antenna gain corresponding to the angle θ in the missile fuze detection field, r is the maximum effective distance, and R is the distance from the chaff particle to the center of the missile fuze.

[0064] In the simulation, the visible point judgment is performed on all the chaff particles at once. As long as the above formula is satisfied, the chaff particles are considered to be in the detection field;

[0065] (63) Simulation calculation of missile fuze detection of chaff cloud: Based on the established missile fuze detection field, the visibility judgment of chaff particles and the visualization simulation of chaff cloud, the detection simulation of missile fuze of helicopter-dropped chaff cloud is completed by calculating the echo of visible chaff particles.

[0066] A detection simulation system for a missile fuze to a chaff cloud dropped by a helicopter is provided. The detection simulation system is based on the detection simulation method for a missile fuze to a chaff cloud dropped by a helicopter, and realizes the detection simulation of a missile fuze to a chaff cloud dropped by a helicopter.

[0067] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, based on the method for simulating the detection of a helicopter-dropped chaff cloud by a missile fuze, the detection simulation of the helicopter-dropped chaff cloud by the missile fuze is realized.

[0068] A computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the detection simulation of a missile fuze on a helicopter-dropped chaff cloud is realized based on the detection simulation method of a missile fuze on a helicopter-dropped chaff cloud.

[0069] Compared with existing technologies, this invention offers the following significant advantages: 1) It utilizes OpenGL to visualize the helicopter wake field using line segments and arrows. 2) It uses C++ containers to store chaff data, enabling visualization of tens of millions of chaff clouds, more realistically and accurately simulating the dynamic diffusion process of chaff clouds and improving model accuracy. 3) The hollow cone missile fuze detection field better reflects actual conditions, making detection simulation more realistic and accurate.

[0070] The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 This is the main flow chart of the simulation method for detecting the helicopter-dropped chaff cloud by a missile fuze according to the present invention.

[0072] Figure 2 for Figure 1 Flowchart of the steps for calculating helicopter wake-induced speed.

[0073] Figure 3 for Figure 1 Flowchart of the steps for modeling chaff cloud motion.

[0074] Figure 4 for Figure 1 Flowchart of the simulation steps for chaff cloud visualization.

[0075] Figure 5 for Figure 1 Flowchart of the simulation steps for missile fuze detection of chaff cloud.

[0076] Figure 6 Schematic diagram of the helicopter single-rotor wake model.

[0077] Figure 7 Schematic diagram of the solution for the induced velocity at the wake vortex line node.

[0078] Figure 8 Schematic diagram of the missile fuze detection field model. DETAILED DESCRIPTION

[0079] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0080] like Figure 1 As shown, the detection simulation method of a missile fuze against a helicopter-dropped chaff cloud comprises the following steps:

[0081] (10) Helicopter wake model: Based on the free wake model, a helicopter single rotor blade tip vortex wake model is established;

[0082] The (10) helicopter wake model modeling steps are specifically as follows:

[0083] Establish the wake model of the blade tip vortex: the vortex line control equation is expressed as To control, is the position vector of the vortex line positioning point in the flow field, ψ is the blade azimuth angle, ζ is the wake life angle, is the velocity of the positioning point, which is the resultant velocity of the free stream velocity and the vortex line node induced velocity, and can be expressed as: is the wake velocity at infinity.

[0084] According to the relationship between rotor rotation: ψ=ζ=Ωt, Ω is the rotor speed, t is time. So we can deduce:

[0085]

[0086] Therefore, the wake model of the tip vortex can be rewritten as:

[0087]

[0088] Positioning points for attached vortices, near wakes, and far wakes The resultant velocity of the induced velocity.

[0089] (20) Calculation of helicopter wake induced velocity: Based on the obtained single rotor tip vortex wake model, the induced velocity field at any point in the helicopter wake field is calculated;

[0090] like Figure 2 As shown, the (20) helicopter wake induced speed calculation step includes:

[0091] (21) Calculate the induced velocity of the rotor wake at the spatial point M: According to the helicopter wake model, the wake model is discretized into a linear vortex element. The coordinates of the two end points of the linear vortex element are L1(x1, y1, z1) and L2(x2, y2, z2), respectively. Find the vector The vector coordinate calculation expression is:

[0092]

[0093] The expression of the induced velocity generated by the linear vortex element on the spatial point M is obtained as follows:

[0094]

[0095] in, is the induced velocity vector, Γ is the linear vortex element circulation, h is the distance from point M to the linear vortex element,

[0096]

[0097]

[0098] is the direction vector,

[0099]

[0100] (22) Rotor wake vortex core correction: The vortex core is corrected according to the following formula:

[0101]

[0102] where δ is the turbulent viscosity coefficient, v is the kinematic viscosity coefficient,

[0103]

[0104] r c is the vortex core radius.

[0105] (30) Visual simulation of helicopter wake field: Based on the single rotor blade tip vortex wake model and wake induced velocity, the visual simulation of helicopter wake field is completed using line segments and arrows based on the OpenGL open graphics library;

[0106] The (30) helicopter wake field visualization simulation steps are specifically as follows:

[0107] According to the obtained helicopter wake model and helicopter wake induced velocity, the motion state of the particles in the helicopter wake field is obtained based on C++ programming. As the motion state is updated, the motion trajectories of some particles in the wake field are drawn with line segments based on the OpenGL open graphics library, and the motion directions of some particles in the wake field are drawn with arrows, thus obtaining a visual simulation model of the helicopter wake field.

[0108] (40) Chaff cloud motion modeling: By establishing a single chaff motion model under the force of air and combining it with the wake induced velocity, a single chaff motion model under the helicopter wake is obtained. The overall diffusion motion model of the chaff cloud under the helicopter wake is obtained by generalizing the single chaff motion model.

[0109] like Figure 4 As shown, the (40) foil cloud motion modeling step includes:

[0110] (41) Solution of helicopter wake wind force: Based on the obtained helicopter wake model and induced velocity, it is converted into the wake wind force on the foil strip through the following formula:

[0111] F wl =0.5ρv 2 S,

[0112] ρ is the air density, S = d × l / 4, d is the foil diameter, l is the foil length, and v is the induced velocity;

[0113] (42) Establish a force model for a single foil strip: When a single foil strip moves in the air, it is subjected to a vertical downward gravity G and an upward buoyancy F. fs , and the movement speed V cs Opposite air resistance F cs 、Wake wind force F wl , where the gravity acting on a single foil strip is:

[0114] G=mg,

[0115] m is the mass of a single foil strip, g is the acceleration due to gravity,

[0116] Buoyancy F fs =ρgV,

[0117] V is the volume of the foil strip. When the foil strip moves at a speed lower than 100 m / s, the air resistance it encounters is:

[0118] F cs =C D ρSV cs ,

[0119] C D is the drag coefficient. When the foil moves at a speed higher than 100 m / s, the air resistance it encounters is:

[0120]

[0121] (43) Establish a single chaff motion model: the velocity V0 of the chaff bomb when it is thrown out of the aircraft is the initial velocity V of the chaff bomb c With the aircraft speed V f The synthesis formula is:

[0122]

[0123] Where θ c is the installation angle of the chaff jet dispenser on the aircraft;

[0124] According to the force model of a single foil strip and the initial velocity of the foil strip, the components of the foil strip velocity on the three axes at any time are obtained:

[0125]

[0126] The sign function is the sign function, V CS0X 、V CS0Y 、V CS0Z are the components of the initial velocity of the foil strip on the three axes, and then the displacement components of a single foil strip on the three axes at any time are calculated according to the above formula, thereby obtaining the position of the foil strip at any time;

[0127] (44) Foil cloud motion modeling: Based on the single foil motion model, the foil cloud motion model is obtained by superimposing and generalizing the single foil motion vector.

[0128] (50) Visual simulation of chaff cloud: Based on the overall diffusion motion model of chaff cloud under the helicopter wake, a visualization simulation of the dynamic diffusion of chaff cloud with tens of millions of particles is completed based on the particle system;

[0129] like Figure 5 As shown, the (50) foil cloud visualization simulation step includes:

[0130] (51) Foil strip particle modeling: Gray particles are used to replace cylindrical foil strips for visual simulation in OpenGL. At the same time, a structure is constructed based on the C++ language to store foil strip related information. The foil strip particle structure stores the key information required to calculate the foil strip motion state, including the motion information of each foil strip itself, including speed and azimuth, and the foil strip's own property information, including mass, length, and survival time. It also contains some information about the foil strip cloud where the foil strip is located, including the particle spacing in the foil strip cloud, the foil strip cloud radius, and the volume;

[0131] (52) Visualization of foil cloud: After the foil particles are initialized, their activation state is determined. The activated foil particles calculate their force state and position information, and continuously update the relevant information as the simulation time progresses. The unactivated particles maintain their original state. Based on the foil position, color, transparency and other related properties stored in the foil particle structure, the visualization simulation of tens of millions of foil particles is completed based on the OpenGL open graphics library.

[0132] (60) Simulation of missile fuze detection of chaff cloud: A hollow cone missile fuze detection field is established to determine the visibility of chaff particles in the detection field. Based on this, a simulation of missile fuze detection of helicopter-dropped chaff cloud is performed.

[0133] like Figure 6 As shown, the (60) missile fuze chaff cloud detection simulation step includes:

[0134] (61) Missile fuze detection field modeling: Based on the relevant parameters of the missile fuze such as the effective range and beam thickness, a hollow cone missile fuze detection field is established.

[0135] (62) Chaff particle visibility judgment: The following formula is used to judge whether all chaff particles under the influence of helicopter wake are within the missile fuze detection field:

[0136] g(θ)·r>R,

[0137] Where g(θ) represents the normalized antenna gain corresponding to the angle θ in the missile fuze detection field, r is the maximum effective distance, and R is the distance from the chaff particle to the center of the missile fuze.

[0138] In the simulation, the visible point judgment is performed on all the foil particles at once. As long as the above formula is satisfied, the foil particles are considered to be in the detection field.

[0139] (63) Simulation calculation of missile fuze detection of chaff cloud: Based on the established missile fuze detection field, the visibility judgment of chaff particles and the visualization simulation of chaff cloud, the detection simulation of missile fuze of helicopter-dropped chaff cloud is completed by calculating the echo of visible chaff particles.

[0140] The present invention also proposes a detection simulation system for a missile fuze to a chaff cloud dropped by a helicopter. Based on the detection simulation method for a missile fuze to a chaff cloud dropped by a helicopter, the detection simulation of a missile fuze to a chaff cloud dropped by a helicopter is realized.

[0141] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, based on the method for simulating the detection of a helicopter-dropped chaff cloud by a missile fuze, the detection simulation of the helicopter-dropped chaff cloud by the missile fuze is realized.

[0142] A computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the detection simulation of a missile fuze on a helicopter-dropped chaff cloud is realized based on the detection simulation method of a missile fuze on a helicopter-dropped chaff cloud.

[0143] In summary, the present invention starts from the force motion model of the foil strip, calculates the helicopter wake induced velocity of the foil strip after it is dropped, analyzes the force condition of the foil strip in the helicopter wake field, solves the problem of analyzing the motion characteristics of the foil strip under the action of the helicopter wake, and by modeling the missile fuze detection field and judging the visibility of the helicopter-dropped foil cloud in the detection field, it can complete the detection simulation of the missile fuze on the tens of millions of moving foil strip clouds. The simulation model is more accurate, and the simulation result is more credible than the simplified model.

[0144] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0145] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A method for simulating the detection of a helicopter-dropped chaff cloud by a missile fuze, characterized in that: The steps include: (10) Helicopter wake model: Based on the free wake model, a helicopter single rotor blade tip vortex wake model is established; (20) Calculation of helicopter wake induced velocity: Based on the single rotor tip vortex wake model, calculate the induced velocity field at any point in the helicopter wake field; (30) Visual simulation of helicopter wake field: Based on the single rotor blade tip vortex wake model and wake induced velocity, the visual simulation of helicopter wake field is completed using line segments and arrows based on the OpenGL open graphics library; (40) Chaff cloud motion modeling: Establish a single chaff motion model under the force of air, and combine it with the wake induced velocity to obtain a single chaff motion model under the helicopter wake. The single chaff motion model is generalized to obtain the overall diffusion motion model of the chaff cloud under the helicopter wake. (50) Visual simulation of chaff cloud: Based on the overall diffusion motion model of chaff cloud under the helicopter wake, a visualization simulation of the dynamic diffusion of chaff cloud with tens of millions of particles is completed based on the particle system; (60) Simulation of missile fuze detection of chaff cloud: Establish a hollow cone missile fuze detection field, determine the visibility of chaff particles in the detection field based on the overall diffusion motion model of the chaff cloud, and simulate the detection of helicopter-dropped chaff cloud by missile fuze based on chaff cloud visualization simulation and chaff particle visibility judgment; The (10) helicopter wake model is modeled, the steps comprising: Vortex line control equation To control, is the position vector of the vortex line positioning point in the flow field, ψ is the blade azimuth angle, ζ is the wake life angle, is the velocity of the positioning point, which is the resultant velocity of the free stream velocity and the vortex line node induced velocity, expressed as: is the wake velocity at infinity; According to the relationship between rotor rotation: ψ=ζ=Ωt, Ω is the rotor speed, t is time, it can be deduced that: Therefore, the wake model of the tip vortex is: Positioning points for attached vortices, near wakes, and far wakes The resultant velocity of the induced velocity; The (40) foil cloud motion modeling step comprises: (41) Solution of helicopter wake wind force: Based on the obtained single rotor blade tip vortex wake model and induced velocity, it is converted into the wake wind force F acting on the foil strip through the following formula: wl , F wl =0.5pv 2 S, ρ is the air density, S = d × l / 4, d is the foil diameter, l is the foil length, and v is the induced velocity; (42) Establish a force model for a single foil strip: When a single foil strip moves in the air, it is subjected to a vertical downward gravity G and an upward buoyancy F. fs , and the movement speed V cs Opposite air resistance F cs 、Wake wind force F wl , where the gravity acting on a single foil strip is: G=mg, m is the mass of a single foil strip, g is the acceleration due to gravity, Buoyancy F fs =ρgV, V is the volume of the foil strip. When the foil strip moves at a speed lower than 100 m / s, the air resistance it encounters is: F cs =C D ρSV cs , C D is the drag coefficient. When the foil moves at a speed higher than 100 m / s, the air resistance it encounters is: (43) Establish a single chaff motion model: the velocity V0 of the chaff bomb when it is thrown out of the aircraft is the initial velocity V of the chaff bomb c With the aircraft speed V f The synthesis formula is: Where θ c is the installation angle of the chaff jet dispenser on the aircraft; According to the force model of a single foil strip and the initial velocity of the foil strip, the components of the foil strip velocity on the three axes at any time are obtained: The sign function is the sign function, V cs X, V cs Y, V cs Z is the component of the motion velocity on the three axes, F cs X, F cs Y, V cs Z is the component of air resistance on the three axes, F wlX 、F wlY 、F wlZ is the component of the wake wind force on the three axes, V CS0X 、V CS0Y 、V CS0Z are the components of the initial velocity of the foil strip on the three axes, and then the displacement components of a single foil strip on the three axes at any time are calculated according to the above formula, thereby obtaining the position of the foil strip at any time; (44) Foil cloud motion modeling: Based on the single foil motion model, the foil cloud motion model is obtained by superimposing and generalizing the single foil motion vector.

2. The method for simulating detection of a helicopter-dropped chaff cloud by a missile fuze according to claim 1, wherein: The (20) helicopter wake induced speed calculation step comprises: (21) Calculate the induced velocity of the rotor wake at the spatial point M: According to the single rotor tip vortex wake model, the wake model is discretized into a linear vortex element. The coordinates of the two end points of the linear vortex element are L1(x1, y1, z1) and L2(x2, y2, z2), respectively. Calculate the vector The vector coordinate calculation expression is: The expression of the induced velocity generated by the linear vortex element on the spatial point M is obtained as follows: in, is the induced velocity vector, Γ is the linear vortex element circulation, h is the distance from point M to the linear vortex element, is the direction vector, (22) Rotor wake vortex core correction: The vortex core is corrected according to the following formula: where δ is the turbulent viscosity coefficient, v is the kinematic viscosity coefficient, and ζ 0 is the initial value of the wake life angle, The corrected induced velocity calculation formula is: r c is the vortex core radius.

3. The method for simulating detection of a helicopter-dropped chaff cloud by a missile fuze according to claim 2, wherein: The (30) helicopter wake field visualization simulation comprises the following steps: According to the obtained helicopter wake model and helicopter wake induced velocity, the motion state of the particles in the helicopter wake field is obtained based on C++ programming. As the motion state is updated, the motion trajectories of some particles in the wake field are drawn with line segments based on the OpenGL open graphics library, and the motion directions of some particles in the wake field are drawn with arrows, thus obtaining a visual simulation model of the helicopter wake field.

4. The method for simulating detection of a helicopter-dropped chaff cloud by a missile fuze according to claim 1, wherein: The (50) foil cloud visualization simulation comprises the following steps: (51) Foil strip particle modeling: Gray particles are used to replace cylindrical foil strips for visual simulation in OpenGL. At the same time, a structure is constructed based on the C++ language to store foil strip related information. The foil strip particle structure stores the key information required to calculate the foil strip motion state, including the motion information of each foil strip itself, including speed and azimuth, and the foil strip's own property information, including mass, length, and survival time. It also contains some information about the foil strip cloud where the foil strip is located, including the particle spacing in the foil strip cloud, the foil strip cloud radius, and the volume; (52) Visual simulation of foil cloud: After the foil particles are initialized, their activation state is determined. The activated foil particles calculate their force state and position information, and continuously update the relevant information as the simulation time progresses. The inactivated particles maintain their original state. Based on the foil position, color, and transparency stored in the foil particle structure, the visual simulation of tens of millions of foil particles is completed based on the OpenGL open graphics library.

5. The method for simulating detection of a helicopter-dropped chaff cloud by a missile fuze according to claim 4, wherein: The (50) missile fuze emulation for chaff cloud detection comprises the following steps: (61) Missile fuze detection field modeling: Based on the missile fuze action range and beam thickness, a hollow cone missile fuze detection field is established; (62) Chaff particle visibility judgment: All chaff particles under the influence of helicopter wake are judged to be within the missile fuze detection range according to the following formula: g(θ)·r>R, Where g(θ) represents the normalized antenna gain corresponding to the angle θ in the missile fuze detection field, r is the maximum range of action, and R is the distance from the chaff particle to the center of the missile fuze; In the simulation, the visible point judgment is performed on all the chaff particles at once. As long as the above formula is satisfied, the chaff particles are considered to be in the detection field; (63) Simulation calculation of missile fuze detection of chaff cloud: Based on the established missile fuze detection field, the visibility judgment of chaff particles and the visualization simulation of chaff cloud, the detection simulation of missile fuze of helicopter-dropped chaff cloud is completed by calculating the echo of visible chaff particles.

6. A missile fuze detection simulation system for helicopter-dropped chaff clouds, characterized in that: Based on the method for simulating the detection of a helicopter-dropped chaff cloud by a missile fuze as described in any one of claims 1 to 5, the detection simulation of a helicopter-dropped chaff cloud by a missile fuze is realized.

7. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the method for simulating the detection of a helicopter-dropped chaff cloud by a missile fuze is based on any one of claims 1 to 5, thereby realizing the detection simulation of a helicopter-dropped chaff cloud by a missile fuze.

8. A computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the method for simulating the detection of a helicopter-dropped chaff cloud by a missile fuze according to any one of claims 1 to 5 is used to implement the detection simulation of a helicopter-dropped chaff cloud by a missile fuze.

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