Safety requirement based calculation method for ejection capsule rocket thrust parameters

Abstract

The application discloses a kind of based on safety requirement's ejection hatch cover throw away rocket thrust parameter calculation method, it is related to the technical field of vehicle safety design.The method comprises the following steps: S1, hatch cover throw away parameter initialization, including establishing hatch cover throw away flight simulation coordinate system, hatch cover basic parameter calculation, hatch cover space attitude parameter initialization, hatch cover initial aerodynamic parameter processing and establishing hatch cover throw away rocket thrust parameter initial file;S2, hatch cover throw away flight simulation cyclic iteration;S3, hatch cover throw away requirement compliance determination.The application discloses a kind of based on safety requirement's ejection hatch cover throw away rocket thrust parameter calculation method, through based on safety requirement's calculation and multiple iteration adjustment, can clearly analyze the spatial motion trajectory and divergence direction in hatch cover throw away process, provides scientific, systematic method and basis for the design, evaluation and improvement of ejection hatch cover throw away system, can reduce test cost and risk, improve research and development efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aircraft safety design, in particular to a method for calculating the ejection hatch cover throwing rocket thrust parameter based on safety requirements. BACKGROUND

[0002] The hatch cover throwing rocket thrust three-element design is one of the difficulties in the safety design of the ejection rescue hatch cover throwing. During the ejection rescue process, for the hatch cover fuselage integrated hard-top aircraft, it is not possible to use the cover-penetrating method to open the ejection rescue passage of the aircraft, so it is necessary to use the metal jet cutting method to cut the hatch cover, and then generate thrust by the throwing rocket installed on the hatch cover to push the hatch cover away from the aircraft and pass through the rescue passage to push the ejection seat out of the cabin. However, in order to meet the safety requirements of the hatch cover throwing, the size, direction and point of action of the hatch cover throwing rocket thrust become a difficulty.

[0003] The throwing rocket thrust design is the key to ensure that the hatch cover can be smoothly and safely thrown away. For the throwing rocket throwing force three elements, the thrust size directly affects the speed and effect of the hatch cover throwing. If the thrust is too small, the hatch cover may not be able to be smoothly thrown away, resulting in failure of the ejection rescue passage cleaning; if the thrust is too large, it may generate excessive impact force and acceleration, which cannot meet the requirements of throwing height and throwing distance. Therefore, it is necessary to accurately calculate and control the size of the throwing rocket thrust to ensure that the hatch cover can be thrown away at a suitable speed and force. The thrust direction determines the trajectory of the hatch cover throwing. If the thrust direction is not accurate, the hatch cover may deviate from the expected throwing path, affecting the smooth ejection of the ejection seat and the safety of the flight personnel. Therefore, it is necessary to ensure that the thrust direction of the throwing rocket is consistent with the requirements of the hatch cover throwing to ensure that the hatch cover can be thrown away according to the expected trajectory. The point of action is the position of the thrust on the hatch cover. The selection of the point of action directly affects the stress condition and throwing effect of the hatch cover. If the point of action is not properly selected, it may cause uneven stress on the hatch cover or excessive torque, thereby affecting the throwing effect of the hatch cover and the safety of the flight personnel. Therefore, it is necessary to accurately determine the point of action of the throwing rocket to ensure that the hatch cover can be evenly stressed and smoothly thrown away. The research on the size, direction and point of action of the throwing rocket thrust during the ejection rescue hatch cover throwing is to ensure that the hatch cover can be smoothly and safely thrown away, providing reliable ejection rescue protection for the flight personnel. This requires accurate calculation and testing during the design and manufacturing process to ensure the performance and reliability of the ejection rescue system.

[0004] Ejection rocket thrust design is an important digital test and safety evaluation method for ejection capsule cover ejection flight dynamics simulation. Mainly in the following aspects: first, accuracy. The flight dynamics simulation method can simulate the ejection process of the ejection capsule cover based on physical laws and mathematical models. By inputting the thrust size, direction and action point of the ejection rocket, the simulation system can calculate the key data such as the motion trajectory, speed and acceleration of the capsule cover in the ejection process. This method can provide accurate data support for design. Second, safety. The flight dynamics simulation method can avoid the risks that may occur in actual test, such as ejection cover ejection failure, damage to ejection seat and test personnel, etc. Through simulation, the thrust of the ejection rocket can be simulated and optimized many times without endangering personnel safety, to ensure the performance and reliability of the ejection rescue system. Third, economy. Traditional experimental test method needs to invest a lot of manpower, material resources and financial resources, and the test cycle is long. Compared with the traditional experimental test method, the flight dynamics simulation method has the advantages of low cost and short cycle. Through simulation, the ejection process of the capsule cover under various ejection rocket thrust parameters can be simulated quickly on the computer, thereby greatly saving the time and cost of experimental test. Fourth, repeatability. The flight dynamics simulation method has high repeatability. By setting the same simulation parameters and conditions, the ejection process of the capsule cover under the same ejection rocket thrust parameters can be simulated many times to obtain more reliable results. This repeatability helps to analyze and compare the simulation results in depth, providing reliable basis for design optimization. Fifth, optimization. The flight dynamics simulation method can also be used for optimization design of ejection rescue system. By simulating the ejection process of the capsule cover under different thrust parameters, the optimal combination of thrust size, direction and action point can be found out, thereby further improving the performance and reliability of the ejection rescue system. This optimization method not only improves the design efficiency, but also reduces the design cost. Therefore, the flight dynamics simulation method has the advantages of accuracy, safety, economy, repeatability and optimization in studying the size, direction and action point of the ejection rocket thrust during the ejection of the ejection capsule cover. This method has become one of the important means of modern ejection rescue system design and optimization. SUMMARY

[0005] The purpose of the present application is to provide a safety requirement based ejection capsule cover ejection rocket thrust parameter calculation method. Through calculation and multiple iteration adjustment based on safety requirements, it can ensure that the ejection process of the capsule cover meets the safety requirements and avoids potential safety hazards caused by unreasonable ejection parameters. At the same time, it can clearly analyze the spatial motion trajectory and divergence direction of the ejection process of the capsule cover, which helps to find potential problems and optimize the design.

[0006] To achieve the above object, the application provides a method for calculating the ejection hatch rocket thrust parameter based on safety requirement, and the specific steps are as follows.

[0007] Step S1, hatch ejection parameter initialization, including establishing the hatch ejection flight simulation coordinate system, hatch basic parameter calculation, hatch space attitude parameter initialization, hatch initial aerodynamic parameter processing and establishing the hatch ejection rocket thrust parameter initial file;

[0008] Step S2, hatch ejection flight simulation loop iteration calculation;

[0009] Step S3, hatch ejection requirement compliance determination.

[0010] Preferably, in step S1, the parameter initialization specific steps are as follows:

[0011] Step S11, establishing the hatch ejection flight simulation coordinate system, the coordinate systems involved include three: the ground axis system O e X e Y e Z e , the wind axis system O w X w Y w Z w and the body axis system O b X b Y b Z b ;

[0012] Step S12, hatch basic parameter calculation, calculating the weight , the center of gravity position , the moment of inertia and the inertia product of the hatch according to the hatch CAD model and the mass distribution;

[0013] Step S13, hatch space attitude parameter initialization, determining the aircraft flight state parameter required for the hatch ejection; calculating the hatch ejection flight state parameter, including the flight angle of attack, the flight side slip angle, the hatch flight true airspeed, the flight height and the three-axis angular rate, according to the hatch geometric position relationship and the aircraft attitude parameter;

[0014] Step S14, calculate the initial aerodynamic parameters of the hatch, calculate the aerodynamic parameters of the hatch at this time according to the initial state parameters of the hatch; first, calculate the local atmospheric standard parameters according to the release height, including local temperature , local atmospheric pressure , local atmospheric density , further calculate the hatch flight pressure, the formula is as follows:

[0015] ;

[0016] Among them, is the hatch flight pressure, is the hatch flight vacuum speed;

[0017] Import the hatch basic parameters, hatch space attitude parameters and hatch geometric model into the CFD calculation process to complete the initial state aerodynamic parameter calculation of the release;

[0018] The hatch weight, center of gravity position, moment of inertia, product of inertia, flight angle of attack, flight side slip angle, hatch flight vacuum speed, flight height and three-axis angular rate in steps S12 and S13, and atmospheric standard parameters, release initial state aerodynamic parameters form a hatch parameter input file A2;

[0019] Step S15, generate the initial file of the hatch release rocket thrust parameter, according to the hatch release rocket thrust design, decompose the thrust vector to obtain the release rocket thrust size, thrust modulus time variation law, thrust direction, thrust action point, and write the above parameters into the thrust vector input file A1.

[0020] Preferably, in step S11, the origin of the earth axis system is fixed on the aircraft, the x-axis points north, the y-axis points east, and the z-axis points to the center of the earth; the origin of the wind axis system is defined at the center of mass, the x-axis is along the airspeed direction, the z-axis is perpendicular to the x-axis and is located in the normal plane downward, and the y-axis forms a right-handed coordinate system with the x-axis and the z-axis; the origin of the body axis system is defined at the center of mass, the x-axis points forward, the z-axis is perpendicular to the x-axis and is located in the normal plane downward, and the y-axis forms a right-handed coordinate system with the x-axis and the z-axis.

[0021] Preferably, in step S12, the center of gravity position of the hatch is calculated according to the following formula:

[0022] ;

[0023] ;

[0024] ;

[0025] Among them, , are the hatch simplified split mass number and quantity, respectively, is the first Block mass and block weight , , The first Block mass block three-axis coordinates, , , These are the coordinates of the hatch's center of gravity.

[0026] The formulas for calculating the moment of inertia and product of inertia of the hatch cover are as follows:

[0027] ;

[0028] ;

[0029] in, , , These are the three-axis moments of inertia. , , These are the triaxial inertial products.

[0030] Preferably, in step S2, the specific steps of the canopy jettison flight simulation iteration are as follows:

[0031] Step S21: Derive the control equation set for the flight dynamics simulation of canopy jettison, including three force equations, three torque equations, three attitude equations, and two supplementary equations composed of aerodynamic angle and vacuum velocity, for a total of 11 equations and 11 variables. The control equation set is closed.

[0032] Step S22: Given the discrete time step The number of discrete iteration steps in conventional drop flight simulation, where The iteration time step count sequence number is used; the canopy parameter input file A2 and the thrust vector input file A1 are read, and the data is written into the canopy flight status parameter file A3. International standard units are used when writing, and the angle units involved are converted into radians.

[0033] Step S23: Input the aerodynamic angle, vacuum velocity, local temperature at flight altitude, local pressure, local atmospheric density, and aerodynamic force integral vector parameters of the canopy in the canopy flight state parameter file A3 into the CFD solver, obtain the aerodynamic force and aerodynamic torque of the canopy under the current state through iterative calculation, write them into the canopy aerodynamic parameter output file A4, and set the parameters of the canopy flight state parameter file A3 to empty.

[0034] Step S24, read the hatch flight state parameter file A3 and the hatch aerodynamic parameter output file A4, substitute into the discrete iterative simulation control equation of the hatch jettison flight simulation, solve the hatch flight state parameter under the current state by iterative calculation and save to the storage database, and the iterative loop enters the next step; judge whether the current iteration step number exceeds the total iteration step number, if less than the total iteration step number, write the solved hatch flight state parameter into the hatch flight state parameter file A3, and start the next iteration; repeat the iteration until the current iteration step number equals the total iteration step number to complete the iterative simulation calculation.

[0035] Preferably, in step S3, the specific steps of the hatch jettison requirement compliance determination are as follows:

[0036] Step S31, read the storage database in step S2, separate out the numerical sequence of the flight path angle changing with the iteration step number, solve the velocity projection of the hatch jettison flight motion on the ground axis system according to the displacement kinematics equation, and obtain the three-axis projection of the hatch ground speed; wherein the kinematics equation of the hatch jettison flight motion on the ground axis system is converted through the body axis system, and the formula is as follows:

[0037] ;

[0038] Wherein, is the velocity vector projection on the ground axis system x axis, is the velocity vector projection on the ground axis system y axis, is the velocity vector projection on the ground axis system z axis, is the flight path angle, is the flight path inclination;

[0039] Step S32, according to the displacement kinematics equation in step S31, accumulate and sum according to the iteration step number to obtain:

[0040] ;

[0041] Wherein, is the throw distance, is the lateral distance, is the throw height;

[0042] According to the cumulative summation time history, obtain , and , that is, the throw distance, lateral distance and throw height change with the iteration time history curve, and obtain the hatch space motion trajectory and divergence direction in the hatch jettison process.

[0043] Step S33, is the throw height, that is, the flight height of the hatch jettison relative to the aircraft, which is converted into the flight height of the hatch jettison relative to the ground, and the calculation formula is as follows:

[0044] ;

[0045] wherein, is the height of the hatch from the ground, is the initial height of the aircraft from the ground;

[0046] Step S34, according to the hatch throwing safety requirement, it is judged whether the throwing height, throwing distance and trajectory divergence direction in step S32 meet the requirements, if not, the throwing rocket thrust size, direction and action point are further adjusted, and the simulation iteration is continued; if the requirements are met, the throwing rocket thrust size, throwing force module value change, direction, and the spatial coordinates of the throwing force action point are output, and the ejection rescue hatch throwing rocket thrust calculation is completed.

[0047] Therefore, the present application proposes a kind of ejection hatch throwing rocket thrust parameter calculation method based on safety requirement, and its beneficial effects are as follows:

[0048] (1) the ejection hatch throwing rocket thrust parameter calculation method based on safety requirement proposed in the present application, by the calculation based on safety requirement and multiple iteration adjustment, it can ensure that the hatch throwing process meets the safety requirement, avoids the security risk caused by unreasonable throwing parameter, and protects the safety of pilot.

[0049] (2) the ejection hatch throwing rocket thrust parameter calculation method based on safety requirement proposed in the present application, in combination with multiple coordinate systems, CFD solver and detailed parameter calculation and iteration process, the thrust parameter of ejection hatch throwing rocket can be accurately calculated, including thrust size, direction and action point, to provide accurate data for the design and optimization of ejection system.

[0050] (3) the ejection hatch throwing rocket thrust parameter calculation method based on safety requirement proposed in the present application can clearly analyze the spatial motion trajectory and divergence direction in the process of hatch throwing, has comprehensive mastery to the whole dynamic process of hatch throwing, provides scientific, systematic method and basis for the design, evaluation and improvement of ejection hatch throwing system, can reduce test cost and risk, and improve research and development efficiency.

[0051] The technical solutions of the present application will be described in further detail below by means of drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0052] Figure 1 is the overall calculation flowchart of the ejection hatch throwing rocket thrust parameter calculation method based on safety requirement of the present application;

[0053] Figure 2 is the hatch throwing space flight trajectory example diagram of the ejection hatch throwing rocket thrust parameter calculation method based on safety requirement of the present application;

[0054] Figure 3 Figure 1 is a schematic diagram of the cabin cover ejection plumb velocity change over time according to the cabin cover ejection rocket thrust parameter calculation method based on safety requirements of the present application;

[0055] Figure 4 Figure 2 is a schematic diagram of the cabin cover ejection pitch moment change over time according to the cabin cover ejection rocket thrust parameter calculation method based on safety requirements of the present application. DETAILED DESCRIPTION

[0056] In order to make the technical solutions, advantages and objectives of the present application clearer, the technical solutions of the embodiments of the present application will be described clearly and completely below. The described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the described embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without any creative effort fall within the protection scope of the present application.

[0057] Unless otherwise defined, the technical terms or scientific terms used in the present application shall have the usual meanings understood by those of ordinary skill in the art to which the present application belongs.

[0058] As shown in Figure 1 Figure 1, the present application provides a cabin cover ejection rocket thrust parameter calculation method based on safety requirements, and the specific steps are as follows:

[0059] Step S1, cabin cover ejection parameter initialization, including establishing a cabin cover ejection flight simulation coordinate system, cabin cover basic parameter calculation, cabin cover space attitude parameter initialization, cabin cover initial aerodynamic parameter processing and establishing a cabin cover ejection rocket thrust parameter initial file, and the specific steps are as follows:

[0060] Step S11, establishing a cabin cover ejection flight simulation coordinate system, which involves three coordinate systems: a ground axis system O e X e Y e Z e , a wind axis system O w X w Y w Z w and a body axis system O b X b Y b Z b; wherein, the ground axis system defines the origin fixed on the aircraft, the x-axis points north, the y-axis points east, and the z-axis points to the earth center; the wind axis system defines the origin at the center of mass, the x-axis points along the airspeed direction, the z-axis is perpendicular to the x-axis and lies in the horizontal plane of the canopy pointing downward, and the y-axis forms a right-handed coordinate system with the x-axis and the z-axis; the body axis system defines the origin at the center of mass, the x-axis points forward, the z-axis is perpendicular to the x-axis and lies in the horizontal plane pointing downward, and the y-axis forms a right-handed coordinate system with the x-axis and the z-axis.

[0061] Step S12, canopy basic parameter calculation, calculating the weight of the canopy according to the canopy CAD model and the mass distribution , the center of gravity position , the moment of inertia , and the inertia product ; the canopy center of gravity position calculation formula is as follows:

[0062] ;

[0063] ;

[0064] ;

[0065] wherein, , are the mass block number and the number of the canopy simplified split, respectively, is the weight of the mass block of the th block, , , are the three-axis coordinates of the mass block of the th block, respectively, , , are the coordinates of the center of gravity position of the canopy, respectively;

[0066] The canopy moment of inertia and inertia product calculation formula is as follows:

[0067] ;

[0068] ;

[0069] wherein, , , are the three-axis moments of inertia, respectively, , , are the three-axis inertia products, respectively.

[0070] Step S13, hatch space attitude parameter initialization, determine the flight state parameters of the aircraft that needs to be thrown away the hatch; According to the hatch geometric position relationship, the hatch throwing flight state parameters are calculated through the aircraft attitude parameters, including flight angle of attack, flight sideslip angle, hatch flight true airspeed, flight height and three-axis angular rate; The initial value of the parameter is shown in Table 1.

[0071] Table 1 Main initial simulation parameters of ejection survival hatch throwing

[0072]

[0073] Step S14, calculate the initial aerodynamic parameters of the hatch, calculate the aerodynamic parameters of the hatch at this time according to the initial state parameters of the hatch; First, calculate the local atmospheric standard parameters according to the throwing height, including local temperature , local atmospheric pressure , local atmospheric density , further calculate the hatch flight pressure, the formula is as follows:

[0074] ;

[0075] Among them, is the hatch flight pressure, is the hatch flight true airspeed;

[0076] Import the hatch basic parameters, hatch space attitude parameters and hatch geometric model into the CFD calculation process to complete the initial state aerodynamic parameter calculation of throwing;

[0077] The hatch weight, center of gravity position, moment of inertia, product of inertia, flight angle of attack, flight sideslip angle, hatch flight true airspeed, flight height and three-axis angular rate in step S12 and step S13, as well as atmospheric standard parameters, throwing initial state aerodynamic parameters form a hatch parameter input file A2;

[0078] Step S15, generate the initial file of hatch throwing rocket thrust parameters, according to the hatch throwing rocket thrust design, decompose the thrust vector to obtain the throwing rocket thrust size, thrust modulus time variation law, thrust direction, thrust action point, and write the above parameters into the thrust vector input file A1.

[0079] Step S2, hatch throwing flight simulation loop iteration calculation, the specific steps are as follows:

[0080] Step S21, derive the control equation set of hatch throwing flight dynamics simulation, including three force equations, three moment equations, three attitude equations, two supplementary equations composed of aerodynamic angle and true airspeed, a total of 11 equations and 11 variables, the control equation set is closed;

[0081] Step S22, give a discrete time step and the number of discrete iteration steps of the conventional jettison flight simulation, wherein is the iteration time step count number; reading the hatch parameter input file A2 and the thrust vector input file A1, writing data into the hatch flight state parameter file A3, writing in international standard units, and converting the angle units involved into radians;

[0082] Step S23, inputting the aerodynamic angle, the true airspeed, the local temperature, the local pressure, the local atmospheric density, and the hatch aerodynamic force integral vector parameter in the hatch flight state parameter file A3 into the CFD solver, obtaining the aerodynamic force and the aerodynamic moment of the hatch in the current state through iterative calculation, writing into the hatch aerodynamic parameter output file A4, and emptying the parameters in the hatch flight state parameter file A3;

[0083] Step S24, reading the hatch flight state parameter file A3 and the hatch aerodynamic parameter output file A4, substituting into the discrete iteration simulation control equation group of the hatch jettison flight simulation, solving the hatch flight state parameter in the current state through iterative calculation and saving to the storage database, and entering the next step in the iteration loop; judging whether the current iteration step number exceeds the total iteration step number, if less than the total iteration step number, writing the solved hatch flight state parameter into the hatch flight state parameter file A3, and starting the next iteration; repeating the iteration until the current iteration step number equals the total iteration step number to complete the iterative simulation calculation.

[0084] Step S3, hatch jettison requirement compliance determination, the specific steps are as follows:

[0085] Step S31, reading the storage database in step S2, separating out the numerical sequence of the flight path angle changing with the iteration step number, solving the velocity projection of the hatch jettison flight motion on the ground axis system according to the displacement kinematics equation, and obtaining the three-axis projection of the hatch ground speed; wherein the kinematics equation of the hatch jettison flight motion on the ground axis system is converted through the body axis system, and the formula is as follows:

[0086] ;

[0087] wherein, is the x-axis projection of the true airspeed vector on the ground axis system, is the y-axis projection of the true airspeed vector on the ground axis system, is the z-axis projection of the true airspeed vector on the ground axis system, is the flight path angle, is the flight path inclination angle;

[0088] Step S32, according to the displacement kinematics equation in step S31, summing according to the iteration step number, obtaining:

[0089] ;

[0090] wherein, is the throw distance, is the lateral distance, is the throw height;

[0091] According to the cumulative summation time history, the throw distance, the lateral distance and the throw height are obtained as functions of the iteration time, i.e. , and , i.e. the hatch space motion trajectory and the divergence direction during the hatch ejection process.

[0092] Step S33, is the throw height, i.e. the flight height of the hatch ejection relative to the aircraft, which is converted into the flight height of the hatch ejection relative to the ground, and the calculation formula is as follows:

[0093] ;

[0094] wherein, is the hatch height relative to the ground, is the initial state of the aircraft height relative to the ground; because the z-axis of the coordinate system is defined to point downward to the center of the earth, therefore the front is negative; according to the design requirements, the spatial trajectory of the hatch ejection, the plumb velocity and the pitch moment as functions of time under the conditions of 120 m / s, 150 m / s and 180 m / s true airspeed and 25° ejection angle are obtained as shown in Figure 2 , 3 , 4 respectively.

[0095] Step S34, according to the safety requirements of the hatch ejection, it is determined whether the throw height, the throw distance and the trajectory divergence direction in step S32 meet the requirements, if not, the ejection rocket thrust size, direction and action point are further adjusted, and the simulation iteration is continued; if the requirements are met, the ejection rocket thrust size, the throw force modulus change, the direction, the space coordinates of the throw force action point are output, and the ejection hatch ejection rocket thrust calculation is completed.

[0096] Therefore, the present application provides a kind of based on the safety requirement ejection hatch ejection rocket thrust parameter calculation method, by based on the calculation and multiple iteration adjustment of safety requirement, in combination with multiple coordinate system, CFD solver and detailed parameter calculation and iteration process, the thrust parameter of ejection hatch ejection rocket can be accurately calculated, provides scientific, systematic method and basis for the design, evaluation and improvement of ejection hatch ejection system.

[0097] It should be pointed out finally that the above examples are only used to illustrate the technical solutions of the present application but not to limit it, and although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can still be modified or replaced equivalently, and these modifications or equivalent replacements should not make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present application.

Claims

1. A method for calculating the ejection capsule rocket thrust parameters based on safety requirements, characterized by, The specific steps are as follows: Step S1, the hatch throwing parameter initialization, including establishing the hatch throwing flight simulation coordinate system, the hatch basic parameter calculation, the hatch space attitude parameter initialization, the hatch initial aerodynamic parameter processing and establishing the hatch throwing rocket thrust parameter initial file; Step S2, the hatch throwing flight simulation loop iteration calculation; Step S3, the hatch throwing requirement compliance determination; In step S2, the hatch throwing flight simulation loop iteration specific steps are as follows: Step S21, the hatch throwing flight dynamics simulation control equation set is derived, including three force equations, three moment equations, three attitude equations, two supplementary equations composed of aerodynamic angle and true airspeed, a total of 11 equations and 11 variables, and the control equation set is closed; Step S22, given discrete time step and the number of discrete iteration steps of the conventional throw-off flight simulation, where j is the iteration time step count index; read the hatch parameter input file A2 and the thrust vector input file A1, and write data into the hatch flight state parameter file A3, using international standard units, and the angle units involved are converted into radians; Step S23, the aerodynamic angle, true airspeed, local temperature, local pressure, local atmospheric density and hatch aerodynamic force integral vector parameters in the hatch flight state parameter file A3 are input into the CFD solver, the aerodynamic force and the aerodynamic moment of the hatch under the current state are obtained through iterative calculation, written into the hatch aerodynamic parameter output file A4, and the hatch flight state parameter file A3 parameters are emptied; Step S24, the hatch flight state parameter file A3 and the hatch aerodynamic parameter output file A4 are read, substituted into the hatch throwing flight simulation discrete iteration simulation control equation set, the hatch flight state parameters under the current state are solved through iteration and saved to the storage database, and the iteration loop enters the next step; whether the current iteration step number exceeds the total iteration step number is judged, if less than the total iteration step number, the solved hatch flight state parameters are written into the hatch flight state parameter file A3, and the next iteration is started, until the current iteration step number is equal to the total iteration step number, and the iteration simulation calculation is completed; In step S3, the specific steps of the hatch throwing requirement compliance determination are as follows: Step S31, the storage database in step S2 is read, the numerical sequence of the track angle changing with the iteration step number is separated out, the velocity projection of the hatch throwing flight motion on the ground axis system is solved according to the displacement kinematics equation, and the hatch ground speed three-axis projection is obtained; wherein the kinematics equation of the hatch throwing flight motion on the ground axis system is converted through the body axis system, and the formula is as follows: ； wherein, is the projection of the airspeed vector on the x-axis of the earth axis system, is the projection of the airspeed vector on the y-axis of the earth axis system, is the projection of the airspeed vector on the z-axis of the earth axis system, is the track angle, is the track inclination; Step S32, according to the displacement kinematics equation in step S31, the iteration step number is accumulated to obtain: ； wherein is the throw distance, is the lateral distance, is the throw height; According to the cumulative summation time history, the throw distance, lateral distance and throw height with iteration time history curves are obtained, i.e. , and , the hatch cover space motion trajectory and divergence direction during the hatch cover throwing process are obtained. Step S33, For the throw, i.e. the height of the hatch throw relative to the flying height of the aircraft, converted to the flying height of the hatch throw relative to the ground, the following formula applies: ； wherein, is the height of the hatch above the ground, is the height of the aircraft above the ground in the initial state; Step S34, according to the hatch throwing safety requirement, whether the throw height, throw distance and track divergence direction in step S32 meet the requirements are determined, if not, the throw rocket thrust size, direction and action point are further adjusted, and the simulation iteration is continued; if the requirements are met, the throw rocket thrust size, throw force module value change, direction and throw force action point space coordinates are output, and the ejection rescue hatch throwing rocket thrust calculation is completed.

2. The method for calculating the ejection capsule rocket thrust parameters based on the safety requirements according to claim 1, characterized in that, In step S1, the parameter initialization specific steps are as follows: Step S11, establish the hatch throwing flight simulation coordinate system, involving three coordinate systems: the ground axis system O e X e Y e Z e , the wind axis system O w X w Y w Z w and the body axis system O b X b Y b Z b ; Step S12, hatch basic parameter calculation, calculating the weight of the hatch according to the hatch CAD model and the mass distribution , the center of gravity position , the moment of inertia and the product of inertia ; Step S13, the hatch space attitude parameter initialization determines the aircraft flight state parameters required for the hatch throwing; according to the hatch geometric position relationship, the hatch throwing flight state parameters are calculated through the aircraft attitude parameters, including the flight angle of attack, the flight sideslip angle, the hatch flight true airspeed, the flight height and the three-axis angular velocity; Step S14, calculating the initial aerodynamic parameters of the hatch cover, calculating the aerodynamic parameters of the hatch cover according to the initial state parameters of the hatch cover; first, calculating the local atmospheric standard parameters according to the release height, including the local temperature , the local atmospheric pressure , the local atmospheric density , further calculating the flight pressure of the hatch cover, the formula is as follows: ； wherein, is the cabin flight air pressure, is the cabin flight true air speed; The hatch basic parameters, hatch space attitude parameters and hatch geometric model are introduced into the CFD calculation process to complete the calculation of the aerodynamic parameters of the initial state of the throwing; The hatch weight, center of gravity position, moment of inertia, product of inertia, flight angle of attack, flight side slip angle, flight true airspeed, flight altitude and three-axis angular rate in steps S12 and S13, and the atmospheric standard parameters and the aerodynamic parameters of the initial state of the throwing are used to form a hatch parameter input file A2; In step S15, the initial file of the hatch throwing rocket thrust parameters is generated. According to the design of the hatch throwing rocket thrust, the thrust vector is decomposed to obtain the throwing rocket thrust size, time variation law of the thrust modulus, thrust direction and thrust action point, and the above parameters are written into the thrust vector input file A1.

3. The method of claim 2, wherein the method is characterized by: In step S11, the origin of the ground axis system is fixed on the aircraft, the x-axis points north, the y-axis points east, and the z-axis points to the center of the earth; the origin of the wind axis system is defined at the center of mass, the x-axis is along the airspeed direction, the z-axis is perpendicular to the x-axis and is located in the normal plane downward, and the y-axis forms a right-handed coordinate system with the x-axis and the z-axis; the origin of the body axis system is defined at the center of mass, the x-axis points forward, the z-axis is perpendicular to the x-axis and is located in the normal plane downward, and the y-axis forms a right-handed coordinate system with the x-axis and the z-axis.

4. The method of claim 2, wherein the method is characterized by: In step S12, the center of gravity position of the hatch is calculated according to the following formula: ； ； ； wherein, , are the hatch cover simplified split mass number and quantity, respectively, is the first mass block weight, , , are the first mass block three-axis coordinates, , , are the hatch cover center of gravity position coordinates, respectively; The moment of inertia and the product of inertia of the hatch are calculated according to the following formula: ； ； wherein , , are the three principal moments of inertia, respectively, , , are the three principal products of inertia, respectively.

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