CN103293397A - Method for generating aircraft initial lightening stroke attachment points - Google Patents

Abstract

The invention discloses a method for generating aircraft initial lightning stroke attachment points, and belongs to the technical field of aircraft lightning direct effect simulation. The method includes the steps of firstly, selecting a simulation area, calculating the probability pi that a discharge channel develops toward each possible yielding point i each time, calculating the potential of a discharge point possibly developing after one of the possible yielding points is determined as a next yielding point through a wheel disc rotating method according to the probability, adjusting the border condition of the simulation area according to the potential, repeatedly calculating until the requirements that a thunder channel hits an aircraft or downlink guide develops to the border of solution space are met, recoding the number of times that thunder hits the air craft in each discharge process and the number of times that a certain part of the aircraft is hit, and obtaining the lightning stroke probability of each part. When the method is adopted to conduct aircraft thunder partition, limitation of an analog method is avoided, the method is closer to a practical situation in comparison with an induced electric field simulation method, and the method saves more time and is safer and more economic in comparison with a ground experiment and a flight experiment.

Description

A kind of initially be struck by lightning method of attachment point of aircraft that generates

Technical field

The invention belongs to aircraft thunder and lightning direct effect simulation technical field, relate in particular to a kind of initially be struck by lightning emulation mode of attachment point of aircraft that generates.

Background technology

Thunder and lightning is the spontaneous phenomenon that can not evade in the aircraft flight, the thunder and lightning direct effect refers to be struck by lightning and costs aircraft, lightning current is by time heating even puncture outside mounted component such as aircraft skin, radome, destroy the phenomenon of aircraft physical arrangement, because the thunderbolt to aircraft is directly connected to flight safety, so must carry out the lightning Protection design of aircraft in advance.There are numerous standards to mention the experiment of thunder and lightning direct effect and the lightning protection of aircraft both at home and abroad, as: SAE ARP5416(aircraft thunder and lightning test method); SAEARP5414A(aircraft thunder and lightning subregion), the 23rd joint " thunder and lightning direct effect " among the RTCA/DO.160 " airborne equipment environmental baseline and test procedure ", these standards have great influence power and widespread use in the international airline field.China's respective standard has HB6129 and GJB3567A.According to above standard, aircraft thunder and lightning subregion is divided into 1 district substantially--the attachment region that initially is struck by lightning, 2 districts--impact zone and 3 districts are scanned in thunderbolt--extremely low probability lightning strike area.The lightning protection design of each parts need be carried out according to different thunder and lightning subregions, and the thunder and lightning subregion at first will be determined the attachment point that initially is struck by lightning.So the physical phenomenon that the simulating nature thunder and lightning takes place generates the initial thunderbolt attachment point of aircraft, and relevant position and probability that record is struck by lightning are the crucial first steps of determining aircraft thunder and lightning subregion.

According to present literature survey, the lightning region of new developmental flight device define 4 kinds of methods: 1) first method, by comparing with the similar known aircraft thunderbolt subregion of contour structures, and rule of thumb adjust subregion: these class methods are the simplest, but can only be applied to all highly similar aircraft of material and structure, the scope of application is too little; 2) second method is by the high-voltage testing equipment of testing laboratory, to the full-scale or scale model discharge of aircraft, the test of record thunderbolt attachment point obtains: this experimental technique is more accurate, be each standard recommendation method, but obvious consumptive material consuming time, and high-voltage electric shock arranged or ignite etc. dangerous.3) the third method, there is the scholar to propose to adopt the condition identical with second method (the thunderbolt attachment point test of testing laboratory) to carry out analogue simulation recently, value by electrostatic field calculating aircraft surface induction electric field is determined aircraft thunder and lightning subregion: this emulation mode has certain scientific basis, but having ignored thunderbolt itself is probability event, must discharge more than 10 times so second method is just stipulated each assigned position of sparking electrode.And this method directly is equal to the lightning strike area division with the value of induction field, with true experiment deviation is arranged.Can cause than mistake in the application.4) the 4th kind of method uses true aircraft to leap thunderstorm belt, directly records aircraft nature lightning subregion: this experimental technique result is the most accurate, but this method is obviously very dangerous, and testing expenses are extremely expensive, and seek thunderstorm belt because of needs and repeatedly take a flight test, the test period is also longer.

Summary of the invention

The purpose of this invention is to provide a kind of initially be struck by lightning emulation test method of attachment point of aircraft that generates, the dielectric breakdown of following takes place and contains the discharge threshold model to calculate the thunder and lightning field that has thunder and lightning passage and aircraft simultaneously with the employing finite difference method based on the fractal phenomenon of nature thunder and lightning, can effectively determine initially the be struck by lightning position of attachment point of aircraft, can record the lightning strike probability of its each parts, for aircraft thunder and lightning subregion provides foundation.

A kind of initially be struck by lightning method of attachment point of aircraft that generates that the present invention proposes may further comprise the steps:

The first step, selected simulated domain is set thunder and lightning reference position and position of aircraft, calculates the simulated domain space potential and distributes.

Getting length and width tall and big is simulated domain in the square air box that equals 3 times of model aircraft full-sizes, the reference position of setting thunder and lightning is that the initial breakdown point is positioned at air box top center, and the reference position below that aircraft is positioned at thunder and lightning is that model aircraft full-size is located for 1.5 times apart from the reference position of thunder and lightning; Adopt method of finite difference to calculate electromotive force in the simulated domain, the Potential Distributing on simulated domain outer boundary and the inner boundary that is made of discharge channel constitutes Dirichlet(Di Li Cray jointly) boundary condition, the electromotive force in the described simulated domain

Satisfy Laplace(Laplce) equation, that is:

Wherein

Be the border (comprising inner boundary and outer boundary) of simulated domain Ω, x, y, z are the coordinate of any arbitrarily in the simulated domain, and x ', y ', z ' be any any coordinate on the simulated domain border,

Be any electromotive force of any of simulated domain, and f (x ', y ', z ') be the border

Potential function.

In second step, calculate to the Probability p of each point of discharge development that may develop _i:

$p_i=\left\{\begin{array}{c}{(E_{\mathrm{ij}}-E_{\mathrm{th}})}^{\mathrm{\&eta;}}/{\mathrm{\&Sigma;}}_{j(E_{\mathrm{ij}}\&GreaterEqual;E_{\mathrm{th}})}{(E_{\mathrm{ij}}-E_{\mathrm{th}})}^{\mathrm{\&eta;}},E_{\mathrm{ij}}\&GreaterEqual;{\mathrm{<figure-callout\; id="0"\; label="E\; th"\; filenames="HDA00003137682600013.png,HDA00003137682600016.png"\; state="\{\{state\}\}">E</figure-callout>}}_{\mathrm{th}}\\ 0,E_{\mathrm{ij}}<E_{\mathrm{th}}\end{array}\right.---\left(2\right)$

Wherein, Be the point of discharge that possible develop and the field intensity between the current breakdown point, Be the point of discharge electromotive force that may develop in the discharge channel,

Be the breakdown point electromotive force that is connected with the point of discharge that may develop, wherein be the point of discharge that may develop accordingly and the distance between the current breakdown point; E _ThBe discharge threshold electric field intensity, be the influence index of atmospheric environment to discharge channel, characterized the power of Faraday effect, value 0～5 is changeed method according to Probability p by wheel disc _iA point in the point of discharge of selecting at random to develop is next puncture side point, and thunder and lightning passage guide is developed a step;

The 3rd step, the electromotive force of the next breakdown point i that the calculating selection obtains;

Distance along discharge channel between initial breakdown point and the point of discharge that may develop represents that with Σ Δ l then the electromotive force of the point of discharge that may develop in the discharge channel is

Wherein, E _InFor the discharge channel axis to internal electric field,

Reference potential for initial breakdown point.For the first time the current breakdown point in the discharge process is thunder and lightning reference position point for the initial breakdown point, and the current breakdown point in later on each discharge process is the next breakdown point of choosing in the point of discharge that may develop in the last discharge process.

The 4th step, adjust the boundary condition of simulated domain according to the electromotive force of the 3rd next breakdown point that calculate of step, repeat the first step～3rd step, up to satisfy the thunder and lightning passage hit aircraft or descending guide be developed to find the solution space boundary till;

The 5th step repeated the first step～the 4th step, and the record thunder and lightning hits the number of times a of aircraft and hits the number of times a of the some position j of aircraft respectively _j, wherein be the label of aircraft position j;

In the 6th step, hit j the several a in a certain position of aircraft according to thunder and lightning _jHit number of times a with total thunder and lightning, obtain the lightning strike probability a at each position _j/ a.

A kind of initially be struck by lightning method of attachment point of aircraft that generates of the present invention, its advantage is:

The dielectric breakdown model that contains discharge threshold that fractal phenomenon generation is followed based on the nature thunder and lightning, and adopt finite difference method to calculate the emulation lightning stroke process that has thunder and lightning passage and aircraft simultaneously, more meet the actual conditions of the development of nature thunder and lightning passage and thunderbolt aircraft.Can analogue simulation generate the aircraft attachment point that initially is struck by lightning, record attachment point position on aircraft, each position of calculating aircraft suffers lightning strike probability, for aircraft thunder and lightning subregion provides foundation.Calculating shows, adopt method of the present invention carry out aircraft thunder and lightning subregion avoided the limitation of analogy method, than induction field simulation method more near actual conditions, than ground experiment and flight experiment more save time, safety and economy.

Description of drawings

Figure 1A is the constitutional diagram that the thunder and lightning guide hits head under the identical thunder and lightning reference position same aircraft attitude condition that generates of method described in the present invention;

Figure 1B is the constitutional diagram that the thunder and lightning guide hits wing under the identical thunder and lightning reference position same aircraft attitude condition that generates of method described in the present invention;

Fig. 1 C is the constitutional diagram that the thunder and lightning guide does not hit aircraft under the identical thunder and lightning reference position same aircraft attitude condition that generates of method described in the present invention;

Fig. 2 A be under the different attitude of flight vehicle conditions of different thunder and lightning reference positions that generate of method described in the present invention the thunder and lightning guide hit head constitutional diagram;

Fig. 2 B is the constitutional diagram that the thunder and lightning guide hits vertical tail under the different attitude of flight vehicle conditions of the different thunder and lightning reference positions of the generation of method described in the present invention;

Fig. 2 C is the constitutional diagram that the thunder and lightning guide hits tailplane under the different attitude of flight vehicle conditions of the different thunder and lightning reference positions of the generation of method described in the present invention.

Embodiment

The present invention is described in detail below in conjunction with drawings and Examples.

The present invention proposes a kind of initially be struck by lightning emulation test method of attachment point of aircraft that generates may further comprise the steps:

(1) reference position and the position of aircraft of setting thunder and lightning in simulated domain.Adopt method of finite difference to calculate electromotive force in the simulated domain, the Potential Distributing on simulated domain outer boundary and the inner boundary that is made of discharge channel constitutes the Dirichlet boundary condition jointly, satisfies the Laplace equation, namely

Wherein

Be the border (comprising inner boundary and outer boundary) of regional Ω, x, y, z are the coordinate of any arbitrarily in the simulated domain, and x ', y ', z ' be any any coordinate on the simulated domain border,

Be any electromotive force of any of simulated domain, and f (x ', y ', z ') be the border

Potential function.

Set up its full-scale or scale model with reference to aircraft electrical characteristic to be measured among the present invention; According to the experiment regulation setting of relevant thunderbolt attachment point or set up the reference position of thunder and lightning on their own.

(2) calculate to the Probability p of each point of discharge development that may develop _i:

$p_i=\left\{\begin{array}{c}{(E_{\mathrm{ij}}-E_{\mathrm{th}})}^{\mathrm{\&eta;}}/\underset{j(E_{\mathrm{ij}}\&GreaterEqual;E_{\mathrm{th}})}{\mathrm{\&Sigma;}}{(E_{\mathrm{ij}}-E_{\mathrm{th}})}^{\mathrm{\&eta;}},E_{\mathrm{ij}}\&GreaterEqual;{\mathrm{<figure-callout\; id="0"\; label="E\; th"\; filenames="HDA00003137682600013.png,HDA00003137682600016.png"\; state="\{\{state\}\}">E</figure-callout>}}_{\mathrm{th}}\\ 0,E_{\mathrm{ij}}<E_{\mathrm{th}}\end{array}\right.$

Wherein,

Be the point of discharge that possible develop and the field intensity between the corresponding breakdown point;

Be the point of discharge electromotive force that may develop in the discharge channel,

Be the breakdown point electromotive force that is connected with the point of discharge that may develop, wherein Δ l is distance between the point of discharge that may develop accordingly and current breakdown point; E _ThBe discharge threshold electric field intensity, make that the passage axis is E to internal electric field _In, the reference potential of initial breakdown point is η be atmospheric environment to the index that influences of discharge channel, characterized the power of Faraday effect, value 0～5 selects to puncture direction by the wheel disc method of changeing at random according to probability, thunder and lightning passage guide is developed a step;

The dielectric breakdown model that the development of above-mentioned thunder discharge passage adopts nature to follow, thunder and lightning field calculate and adopt method of finite difference.

(3) distance along passage represents that with Σ Δ l then the electromotive force of the point of discharge that may develop in the discharge channel is between initial breakdown point and the point of discharge that may develop

This point of discharge that may develop is the next point of thunder and lightning passage guide development, finishes step discharge.

(4) electromotive force of the point of discharge that may develop that calculates according to step (3) is adjusted the boundary condition of simulated domain, repeating step (1)-(3), up to satisfy the thunder and lightning passage hit aircraft or descending guide be developed to find the solution space boundary till;

(5) repeating step (1)-(4) are recorded thunder and lightning respectively and are hit the position of aircraft and hit the number of times of this position;

(6) according to thunder and lightning hit aircraft a certain position number of times and hit the total degree of aircraft, obtain a certain lightning strike probability that hits the position of aircraft; According to these lightning strike probability data, can provide foundation to aircraft thunder and lightning subregion.

The emulation more than 10 times at least of a kind of initially be struck by lightning method of attachment point of aircraft that generates of the present invention, each thunder and lightning starting point is that each thunder and lightning starting point is no more than 30 degree apart on the sphere in the center of circle with the aircraft.The present invention can be by regulating atmospheric environment to the thunder and lightning passage that the exponential sum discharge threshold is realized various different fractal dimensions under the different atmospheric conditions that influences of discharge channel, meet with the phenomenon of thunderbolt aloft when thereby the simulated flight device flies more realistically, make result of calculation more near actual conditions.

The principle of the inventive method is as follows:

The three-dimensional numerical value simulation of thunder and lightning guide discharge is from the macroscopic appearance of thunder discharge, with Fractal Theory Applications in thunder discharge guide modeling, Laplace equation and regional boundary condition according to the space, determine the Potential Distributing in space, under the charged analytic model framework of charged disk thundercloud, utilize the dielectric breakdown model and introduce discharge threshold E _ThConstruct thunder and lightning guide discharging value modeling algorithm, realized thunder discharge guide's three-dimensional numerical value simulation.

Consider axial electric field that thundercloud produces along the highly approximate variation tendency that is the parabolic function, can according to thundercloud the Electric Field Distribution of ground excitation to electric field in electric field under the cloud and the cloud along carrying out match with different quadratic functions highly respectively.By

(wherein

Be electric potential difference,

Be electric field intensity,

Be the vector line element) just can obtain the Potential Distributing in space behind the integration.The initial boundary condition of numerical simulation is got the Potential Distributing of finding the solution the place, zone boundary.

Under quasistatic approximation, the electromotive force in the simulated domain satisfies the Laplace equation, and the Potential Distributing on simulated domain outer boundary and the inner boundary that is made of discharge channel constitutes the Dirichlet boundary condition jointly.Adopting finite difference method to find the solution thunder and lightning simulated domain built-in potential then distributes.The development of thunder and lightning passage is the coefficient result of determinacy and enchancement factor in this method.Describing according to the development probability that the dielectric breakdown model adopts punctures direction to make that the probability of the big local development of electric field intensity is obeyed in thunder and lightning guide's development big, and the local development probability that electric field intensity is little is little.And this dielectric breakdown model has been introduced discharge threshold voltage and the pressure drop of thunder and lightning channel interior in the progression of lightning leader, has only when the voltage that applies is higher than discharge threshold voltage, and the thunder and lightning guide just may be developed, and the thunder and lightning channel interior is not equipotential.The introducing of discharge threshold electric field intensity has suppressed the growth of side direction upper branch in the insulating medium (as air), makes the satisfied number minimizing of waiting to develop point of discharge, the introducing of discharge channel pressure drop also make the thunder and lightning guide develop than being easier to and stops.

In the numerical simulation process, in view of the complicacy of thunder and lightning initial breakdown mechanism, think the guide originate in field intensity in the cloud surpass the guide start in the threshold region more at random, this starting point also can be specified by the thunder and lightning testing standard.Because the boundary condition of zoning (thunder and lightning simulated domain) is to constitute jointly by the area outer condition of thunder cloud decision with by the internal boundary condition that discharge channel constitutes, discharge every one step of development, internal boundary condition all can change, again find the solution Laplace equation computer memory Potential Distributing, then calculate with following formula and treat the development point development probability function of neighbor point i direction on every side in the leader channel:

$p_i=\left\{\begin{array}{c}{(E_{\mathrm{ij}}-E_{\mathrm{th}})}^{\mathrm{\&eta;}}/\underset{j(E_{\mathrm{ij}}\&GreaterEqual;E_{\mathrm{th}})}{\mathrm{\&Sigma;}}{(E_{\mathrm{ij}}-E_{\mathrm{th}})}^{\mathrm{\&eta;}},E_{\mathrm{ij}}\&GreaterEqual;{\mathrm{<figure-callout\; id="0"\; label="E\; th"\; filenames="HDA00003137682600013.png,HDA00003137682600016.png"\; state="\{\{state\}\}">E</figure-callout>}}_{\mathrm{th}}\\ 0,E_{\mathrm{ij}}<E_{\mathrm{th}}\end{array}\right.$

Wherein,

Be the point of discharge that possible develop and the electric field intensity between the corresponding breakdown point; E _ThBe discharge threshold electric field intensity, make that the passage axis is E to internal electric field _In, the reference potential of initial breakdown point is Be the influence index of atmospheric environment to discharge channel, characterized the power of Faraday effect, value 0～5 selects to puncture direction by the wheel disc method of changeing at random according to probability, and thunder and lightning passage guide is developed a step, finishes step discharge; Adjust the boundary condition of simulated domain according to the electromotive force of the point of discharge that may develop, circulation successively, up to satisfy thunder discharge stop criterion or descending guide be developed to find the solution space boundary till.In this process as hit aircraft and need record and hit position coordinates and each position thunderbolt number of times statistics, can provide foundation for aircraft thunder and lightning subregion.This position number of times/aircraft of the lightning strike probability of a part=thunderbolt aircraft number of times that always is struck by lightning.The zone that lightning strike probability is big is 1 district according to standard code--attachment region initially is struck by lightning.

Below in conjunction with description of drawings one embodiment of the present invention.

The present invention is the attachment point emulation of being struck by lightning of the simplification F4 aircraft scale model of 15m to the length shown in Figure 1A～Fig. 1 C.Aircraft is placed in the space of 60m * 60m * 60m, establishing z=0 plane electromotive force is that 0, z=60m plane electromotive force is 2000.Centered by aircraft, surpass the about equal angles in 25m place apart from the aircraft center and choose the initial occurrence positions of thunder and lightning, 30 ° of angle intervals are so because the model left-right symmetric is only calculated the situation of the initial origination point of thunder and lightning on aircraft right side, require each point to calculate more than 10 times.What Figure 1A～Fig. 1 C showed is that the identical thunder and lightning reference position same aircraft attitude thunder and lightning guide of the generation of method described in the present invention is near the constitutional diagram of aircraft.Need to calculate 10 times in illustrated same thunder and lightning reference position thunder and lightning reference position (30,20,60), wherein 3 times simulation calculation the results are shown in and shows respectively shown in Figure 1A～Fig. 1 C that the thunder and lightning guide hits head, hits wing and does not hit aircraft.Fig. 2 A～Fig. 2 C is that the different attitude of flight vehicle thunder and lightning of the different thunder and lightning reference positions guides of the generation of method described in the present invention are near the constitutional diagram of aircraft.What show respectively among Fig. 2 A～Fig. 2 C is 3 thunderbolt states wherein: 30 ° at aircraft pitch angle, and 0 ° of roll angle is hit head; 0 ° at aircraft pitch angle, 30 ° of roll angle are hit vertical tail; 0 ° at aircraft pitch angle, 0 ° of roll angle is hit tailplane.Can see that by Figure 1A～Fig. 1 C and Fig. 2 A～Fig. 2 C the situation that aircraft runs into thunderbolt has nothing in common with each other at every turn, and have certain probability distribution.This example has been got 37 thunder and lightning starting points altogether, and (x, y z) are made as (30,30,60) respectively to its coordinate, (30,20,60), (30,47,60), (21,15,60), (21,45,60), (15,21,60), (15,39,60), (13,30,60), (30,13 ,-60), (30,47 ,-60), (21,15 ,-60), (21,45 ,-60), (15,21 ,-60), (15,39 ,-60), (13,30 ,-60), (13,60,30), (30,60,47), (30,60,30), (30,60,13), (53,60,47), (53,60,13) (13 ,-60,30), (30,-60,47), (30 ,-60,30), (30 ,-60,13), (53,-60,47), (53 ,-60,13), (0,13,30), (0,7,47), (0,30,30), (0,30,13), (0,53,47), (0,53,13), (0,47,30), (0,30,47), (0,7,13), (30,30 ,-60), each reference position emulation 10 times.Thunder and lightning reference position coordinate is made as (30,30,60) then, changes aircraft pitch and gets 37 kinds of situations altogether with the rolling angle, (luffing angle, rolling angle):

(30.0,0), (26.6,16.1), (16.1,26.6), (0,30.0), (16.1,26.6), (26.6,16.1), (30.0,0), (60.0,0), (56.3,40.9), (40.9,56.3), (0,60.0), (40.9,56.3), (56.3,40.9), (60.0,0), (90.0,0), (90.0,90.0), (90.0,90.0), (62.7,90.0), (90.0,90.0), (90.0,90.0), (90.0,62.7), (60.0,180), (56.3 ,-40.9), (40.9,-56.3), (180 ,-60.0), (40.9 ,-56.3), (56.3,-40.9), (60.0,180), (30.0,180), (26.6,-16.1), (16.1,-26.6), (180 ,-30.0), (16.1 ,-26.6), (26.6,-16.1), (30.0,180), (180,180), (0,0) every kind of situation emulation 10 times.

Simulate 740 thunderbolts altogether, wherein hit aircraft 651 times.The attachment point position distribution of hitting aircraft according to record: hit head 194 times, hit wing 203 times, hit tailplane 99 times, hit vertical tail 84 times, hit other positions 71 times.Use formula: this position number of times/aircraft of the lightning strike probability of a part=thunderbolt aircraft number of times (651 times) that always is struck by lightning calculates the lightning strike probability at each position.

Each position lightning strike probability result of table 1 aircraft relatively

Table 1 is the actual comparison sheet that passes through each thunderstruck probability statistics result in position of aircraft in the flight test that thunderstorm belt carries out of the simulation result of the method for the invention simulation present embodiment and U.S.'s F-4 aircraft.The thunderbolt attachment point that analog simulation of the present invention obtains mainly is distributed in the higher positions of electric field intensity such as the tip of wing, tailplane and vertical tail and head.This is consistent with existing theoretical analysis, because when the thunder and lightning guide approaches aircraft, always induces very strong electric field at these positions, and the ionization that its ambient air produces attracts the thunder and lightning guide to adhere at these positions.And as can be seen from Table 1, the lightning strike probability distribution results that emulation of the present invention obtains is compared with the measured result of F-4 flight test, the difference of probability distribution maximum is 3.2%, and the goodness of fit is higher, illustrated use the present invention to be struck by lightning to carry out simulated experiment be feasible to attachment point.

Claims (5)

1. one kind generates initially the be struck by lightning method of attachment point of aircraft, it is characterized in that, may further comprise the steps:

The first step, selected simulated domain is set thunder and lightning reference position and position of aircraft, adopts method of finite difference to calculate the interior electromotive force of simulated domain;

In second step, calculate to the Probability p of each point of discharge development that may develop _i:

$p_i=\left\{\begin{array}{c}{(E_{\mathrm{ij}}-E_{\mathrm{th}})}^{\mathrm{\&eta;}}/{\mathrm{\&Sigma;}}_{j(E_{\mathrm{ij}}\&GreaterEqual;E_{\mathrm{th}})}{(E_{\mathrm{ij}}-E_{\mathrm{th}})}^{\mathrm{\&eta;}},E_{\mathrm{ij}}\&GreaterEqual;E_{\mathrm{th}}\\ 0,E_{\mathrm{ij}}<E_{\mathrm{th}}\end{array}\right.$

Wherein,

Be the point of discharge that possible develop and the field intensity between the current breakdown point, Be the point of discharge electromotive force that may develop in the discharge channel,

Be the breakdown point electromotive force that is connected with the point of discharge that may develop, wherein Δ l is distance between the point of discharge that may develop accordingly and current breakdown point; E _ThBe discharge threshold electric field intensity, η be atmospheric environment to the index that influences of discharge channel, select to obtain the next direction i that punctures by wheel disc commentaries on classics method at random according to the development probability function, thunder and lightning passage guide is developed a step;

The 3rd step, the electromotive force of the next breakdown point i that the calculating selection obtains;

The 4th step, adjust the boundary condition of simulated domain according to the electromotive force of the 3rd point of discharge that may develop that calculate of step, repeat the first step～3rd step, up to satisfy the thunder and lightning passage hit aircraft or descending guide be developed to find the solution space boundary till;

The 5th step repeated the first step～the 4th step, and the record thunder and lightning hits the number of times a of aircraft and hits the number of times a of the some position j of aircraft respectively _j, wherein be the label of aircraft position j;

In the 6th step, hit j the several a in a certain position of aircraft according to thunder and lightning _jHit number of times a with total thunder and lightning, obtain the lightning strike probability a at each position _j/ a.

2. a kind of initially be struck by lightning method of attachment point of aircraft that generates according to claim 1, it is characterized in that: it is tall and big in equaling the square air cartridge submodel of dummy vehicle full-size more than 3 times that described simulated domain is got length and width, the reference position of setting thunder and lightning is that the initial breakdown point is positioned at described air cartridge submodel top center, and the reference position below that dummy vehicle is positioned at thunder and lightning is that model aircraft full-size is located for 1.5 times apart from the reference position of thunder and lightning.

3. a kind of initially be struck by lightning method of attachment point of aircraft that generates according to claim 1 is characterized in that: the electromotive force in the described simulated domain

Satisfy Laplace's equation, delivery intend area outer and the inner boundary that constituted by discharge channel on Potential Distributing constitute Dirichlet boundary conditions jointly, described Laplace's equation is:

Wherein

Be the border of simulated domain Ω, x, y, z are the coordinate of any arbitrarily in the simulated domain, and x ', y ', z ' be any any coordinate on the simulated domain border,

Be any electromotive force of any of simulated domain, and f (x ', y ', z ') be the border Potential function.

4. a kind of initially be struck by lightning method of attachment point of aircraft that generates according to claim 1, it is characterized in that: described atmospheric environment is 0～5 to the index η value that influences of discharge channel.

5. a kind of initially be struck by lightning method of attachment point of aircraft that generates according to claim 1, it is characterized in that: the electromotive force of the point of discharge that may develop in the described discharge channel is

Atmospheric environment represents with Σ Δ l that to the distance along discharge channel between the point of discharge that discharges logical initial breakdown point and may develop this point of discharge that may develop is the next point of thunder and lightning passage guide development, finishes step discharge; Wherein, E _InFor the discharge channel axis to internal electric field,

Reference potential for initial breakdown point.

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