Method and device for calculating flight load of carrier rocket along trajectory

Abstract

The invention provides a method and device for calculating the flight load of a carrier rocket along a trajectory, and the method comprises the steps: firstly obtaining aerodynamic load data in different states, and then obtaining the aerodynamic load data of a whole rocket substation at any moment through an interpolation function; calculating the flight load of each substation at any moment and the equivalent load of each substation at any moment of the rocket according to rocket flight characteristic parameters in the upstream trajectory data and the aerodynamic load data of the whole rocket substations, so as to quickly calculate the maximum load of each substation cabin section of the trajectory; and the load change characteristics of each substation cabin section in the whole flight process are obtained, and then the maximum load of each substation cabin section is obtained through screening, so that the obtained load result does not have the problem of maximum load state omission, and the design risk can be greatly reduced.

Description

Technical Field

[0001] The present application relates to the technical field of launch vehicle payload calculation, and in particular to a method and device for calculating the flight payload of a launch vehicle along a trajectory. Background Art

[0002] The accuracy of the load calculation of the launch vehicle is related to the safety of the structural design. Inaccurate load calculation may cause the rocket structure to fail or even disintegrate. The rocket is affected by the engine thrust and aerodynamic force during flight. When calculating the load, the traditional method is to select a small number of characteristic state points based on experience for calculation. The calculation states include: maximum axial overload point, maximum dynamic pressure point, maximum dynamic pressure multiplied by total angle of attack point, and maximum lateral overload point. The aerodynamic force of each substation of the rocket is obtained through aerodynamic calculation, and then the axial force, bending moment and shear force are calculated for each station. This calculation method may cause the selected calculation points to fail to fully cover the maximum load on the rocket body during flight. At the same time, since the maximum load of each compartment does not necessarily appear at the same time, the traditional point selection method only calculates a few points, and the load characteristics of each compartment with flight time are unknown. This design will have certain risks, that is, because only a few points are calculated, it is easy to miss the maximum load state point, resulting in the design result not being able to fully envelop the maximum load state, which may cause the rocket structure to fail or even disintegrate. Summary of the invention

[0003] The purpose of this application is to provide a method and device for calculating the flight load of a launch vehicle along a ballistic trajectory, which can obtain the load change characteristics of each substation compartment during the entire flight process, and then screen out the maximum load of each substation compartment. The result obtained in this way does not have the problem of omitting the maximum load state, which can greatly reduce the design risk.

[0004] In order to achieve the above-mentioned purpose, in a first aspect, the present application provides a method for calculating the flight load of a launch vehicle along a trajectory, comprising:

[0005] Obtaining the full-arrow aerodynamic load data and the 0-rudder-deflection aerodynamic load data corresponding to multiple rocket flight state parameters when the rocket is under the condition of 0-rudder-deflection;

[0006] Obtain rudder aerodynamic load data corresponding to multiple rocket flight state parameters under multiple three-channel rudder deflection conditions, and obtain rudder aerodynamic net load data according to the difference between the rudder aerodynamic load data and the 0 rudder deflection rudder aerodynamic load data;

[0007] According to the sum of the rudder aerodynamic net load data and the full arrow aerodynamic load data, the full arrow aerodynamic load data of multiple substations at three-channel rudder deflection angles are obtained;

[0008] Obtain the rocket flight state parameters and three-channel rudder deflection angle at any time in the upstream ballistic data, and use the interpolation function to interpolate the sub-station aerodynamic load data of the whole arrow at multiple three-channel rudder deflection angles to obtain the sub-station aerodynamic load data of the whole arrow at any time;

[0009] The rocket flight characteristic parameters at any moment in the upstream ballistic data are obtained, and the flight load of each substation at any moment is obtained according to the rocket flight characteristic parameters at any moment and the substation aerodynamic load data of the whole arrow at any moment, and the equivalent load of each substation at any moment is obtained according to the flight load of each substation at any moment.

[0010] In some embodiments of the present application, based on the aforementioned scheme, the rocket flight state parameters include the rocket's Mach number, angle of attack and sideslip angle, and the full arrow aerodynamic load data include the rocket's starting point coordinates, end point coordinates, axial force coefficient, normal force coefficient, lateral force coefficient, rolling moment coefficient, yaw moment coefficient and pitch moment coefficient.

[0011] In some embodiments of the present application, based on the aforementioned scheme, full-arrow aerodynamic load data and 0 rudder and yaw aerodynamic load data corresponding to multiple rocket flight state parameters are obtained when the rocket is under the condition of 0 rudder deflection, including: obtaining full-arrow aerodynamic load data and 0 rudder and yaw aerodynamic load data for multiple Mach numbers, multiple angles of attack and multiple sideslip angles when the rocket is under the condition of 0 rudder deflection through computational fluid dynamics simulation.

[0012] In some embodiments of the present application, based on the aforementioned scheme, the three-channel rudder deflection angle includes the pitch channel rudder deflection angle, yaw channel rudder deflection angle, and roll channel rudder deflection angle of the rocket, and the rudder aerodynamic net load data includes the axial force coefficient, normal force coefficient, lateral force coefficient, roll moment coefficient, yaw moment coefficient, and pitch moment coefficient of the rocket.

[0013] In some embodiments of the present application, based on the above scheme, obtaining rudder aerodynamic load data corresponding to multiple rocket flight state parameters under multiple three-channel rudder deflection conditions of the rocket includes:

[0014] The rudder aerodynamic load data at multiple Mach numbers, multiple angles of attack and multiple sideslip angles under the conditions of multiple pitch channel rudder deflection angles, multiple yaw channel rudder deflection angles and multiple roll channel rudder deflection angles are obtained through computational fluid dynamics simulation.

[0015] In some embodiments of the present application, based on the aforementioned solution, the substation aerodynamic load data includes an axial force coefficient of each substation and a normal force coefficient of each substation.

[0016] In some embodiments of the present application, based on the aforementioned scheme, the rocket flight characteristic parameters include the total arrow mass, altitude, dynamic pressure, thrust, overload, the flight load includes axial force, bending moment and shear force, and the equivalent load includes equivalent axial pressure and equivalent axial tension.

[0017] In some embodiments of the present application, based on the above scheme, the flight load of each substation at any time is obtained according to the rocket flight characteristic parameters at any time and the substation aerodynamic load data of the whole arrow at any time, including:

[0018] Calculate the axial force, bending moment and shear force according to the following formula;

[0019]

[0020]

[0021]

[0022] Where, T n is the axial force of the nth substation, M n is the bending moment of the nth substation, Q n is the shear force of the nth substation, Q (i-1) is the shear force of the i-1th substation, CA i is the axial force coefficient of the ith substation, CN i is the normal force coefficient of the ith substation, CN is the sum of the normal force coefficients of all substations, M is the total arrow mass, N x For overload, m i is the station mass of the ith substation, q is the dynamic pressure, s is the reference area, g is the gravitational acceleration, x T is the center of mass of the whole arrow, x i is the centroid position of the ith substation, x i-1 is the centroid position of the i-1th substation, x cp is the pneumatic pressure center position, J z is the moment of inertia of the ith substation.

[0023] In some embodiments of the present application, based on the above solution, the equivalent load of each substation at any time is obtained according to the flight load of each substation at any time, including:

[0024] Calculate the equivalent axial pressure F according to the following formula eq1 and equivalent axial pull F eq2 ,

[0025]

[0026]

[0027] In the formula, F eq1 is the equivalent axial pressure, F eq2 is the equivalent axial pull, and D is the cabin diameter of the nth substation.

[0028] In a second aspect, the present application provides a device for calculating the flight load of a launch vehicle along a trajectory, comprising:

[0029] An acquisition unit, the acquisition unit is used to acquire full-arrow aerodynamic load data and 0-rudder-deflection aerodynamic load data corresponding to a plurality of rocket flight state parameters when the rocket is under a 0-rudder-deflection condition;

[0030] A first calculation unit, the first calculation unit is used to obtain rudder aerodynamic load data corresponding to multiple rocket flight state parameters when the rocket is under multiple three-channel rudder deflection angle conditions, and the first calculation unit is also used to obtain rudder aerodynamic net load data according to the difference between the rudder aerodynamic load data and the 0 rudder deflection rudder aerodynamic load data;

[0031] A second calculation unit, the second calculation unit is used to obtain the sub-station aerodynamic load data of the whole arrow at multiple three-channel rudder deflection angles according to the sum of the rudder aerodynamic net load data and the whole arrow aerodynamic load data;

[0032] A third calculation unit, the third calculation unit is used to obtain the rocket flight state parameters and the three-channel rudder deflection angle at any time in the upstream ballistic data, and interpolate the sub-station aerodynamic load data of the whole arrow of multiple three-channel rudder deflection angles by using an interpolation function to obtain the sub-station aerodynamic load data of the whole arrow at any time;

[0033] The fourth calculation unit is used to obtain the rocket flight characteristic parameters at any moment in the upstream ballistic data, obtain the flight load of each substation at any moment according to the rocket flight characteristic parameters at any moment and the substation aerodynamic load data of the whole arrow at any moment, and obtain the equivalent load of each substation at any moment according to the flight load of each substation at any moment.

[0034] The technical solution of the present application provides a method and device for calculating the flight load of a launch vehicle along a trajectory. The method first obtains aerodynamic load data under different states, then uses an interpolation function to obtain the aerodynamic load data of all rocket substations at any moment, and then calculates the flight load of each substation of the rocket at any moment and the equivalent load of each substation at any moment based on the rocket flight characteristic parameters in the upstream trajectory data and the aerodynamic load data of all rocket substations. In this way, the maximum load of each substation section of the trajectory can be quickly calculated, and the load change characteristics of each substation section during the whole flight process can be obtained, and then the maximum load of each substation section can be screened. The load result obtained in this way does not have the problem of missing the maximum load state, which can greatly reduce the design risk. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0036] In the attached picture:

[0037] Figure 1 This is a flow chart of a method for calculating a flight load of a launch vehicle along a ballistic trajectory according to an embodiment of the present application;

[0038] Figure 2 The axial force curve diagram of the whole arrow at different times obtained by using the method for calculating the flight load of a launch vehicle along the trajectory provided by the embodiment of the present application;

[0039] Figure 3 A graph showing the maximum axial force of a substation compartment changing with time, obtained by using the method for calculating the flight load of a launch vehicle along a trajectory provided in an embodiment of the present application;

[0040] Figure 4 This is a schematic diagram of the structure of a device for calculating the flight load of a launch vehicle along a ballistic trajectory according to an embodiment of the present application. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0042] Some embodiments of the present application will be described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0043] The traditional calculation method of the launch vehicle flight load is as follows:

[0044] 1. The ballistics professional calculates the flight trajectory under different wind directions, and selects the maximum axial overload point, maximum dynamic pressure point, maximum dynamic pressure multiplied by total attack angle point, and maximum lateral overload point state. Each state outputs the corresponding Mach number, attack angle, sideslip angle, altitude and other parameters;

[0045] 2. The pneumatic major uses the above parameters to calculate the pneumatic load and uses the computational fluid dynamics (CFD) simulation method to output the pneumatic load of the substation;

[0046] 3. The load specialist uses the aerodynamic load data, taking into account the mass of the substation and the engine thrust, to obtain the axial force, bending moment and shear force of each substation, and outputs the results to the structure specialist;

[0047] 4. The structural department converts the axial force, bending moment and shear force into equivalent axial pressure / tension, selects the maximum equivalent axial pressure / tension result from the state points calculated by the load department, and performs finite element simulation.

[0048] It can be seen that the traditional method of calculating the flight payload of a launch vehicle requires the participation of four disciplines to complete a round of payload calculation. There is data flow between the disciplines. At the same time, the CFD simulation of the aerodynamics discipline often takes a long time and is a breakpoint in the process, which makes it impossible to achieve rapid iteration.

[0049] Different from the traditional method for calculating the flight load of a launch vehicle, the embodiment of the present application provides a method for calculating the flight load of a launch vehicle along a trajectory, which connects the four professional interfaces of trajectory, aerodynamics, load, and structure, and can realize the rapid calculation of the flight load, such as Figure 1 As shown, the method comprises the following steps:

[0050] Step S1, obtaining full-arrow aerodynamic load data and 0-rudder deflection aerodynamic load data corresponding to a plurality of rocket flight state parameters when the rocket is under the condition of 0-rudder deflection;

[0051] Specifically, the rocket flight state parameters include the rocket's Mach number, angle of attack and sideslip angle, etc. The full-rocket aerodynamic load data include the rocket's starting point coordinates, end point coordinates, axial force coefficient, normal force coefficient, lateral force coefficient, rolling moment coefficient, yaw moment coefficient and pitch moment coefficient, etc.

[0052] In some embodiments, in step S1, the full arrow aerodynamic load data and the 0 rudder deflection aerodynamic load data of multiple Mach numbers, multiple angles of attack and multiple sideslip angles under the condition of 0 rudder deflection are obtained through CFD simulation. In order to facilitate subsequent analysis, the full arrow aerodynamic load data table of 0 rudder deflection can be formed according to the full arrow aerodynamic load data. Among them, the form of some 0 rudder deflection full arrow aerodynamic load data tables is shown in Table 1. In Table 1, Ma is the Mach number, beta is the sideslip angle, alpha is the angle of attack, and Xbeg, Xend, CA, CN0, CZ, C1, Cn, and Cm are the starting point coordinates, the end point coordinates, the axial force coefficient, the normal force coefficient, the lateral force coefficient, the rolling moment coefficient, the yaw moment coefficient, and the pitching moment coefficient, respectively.

[0053] Table 1

[0054]

[0055]

[0056]

[0057] Step S2, obtaining rudder aerodynamic load data corresponding to multiple rocket flight state parameters when the rocket is under multiple three-channel rudder deflection angle conditions, and obtaining rudder aerodynamic net load data according to the difference between the rudder aerodynamic load data and the 0 rudder deflection rudder aerodynamic load data;

[0058] Specifically, the three-channel rudder deflection angle includes the rocket's pitch channel rudder deflection angle, yaw channel rudder deflection angle, and roll channel rudder deflection angle, and the rudder aerodynamic net load data includes the rocket's axial force coefficient, normal force coefficient, lateral force coefficient, rolling moment coefficient, yaw moment coefficient, and pitch moment coefficient.

[0059] In some embodiments, in step S2, rudder aerodynamic load data of multiple Mach numbers, multiple angles of attack and multiple sideslip angles under the conditions of multiple pitch channel rudder deflection angles, multiple yaw channel rudder deflection angles and multiple roll channel rudder deflection angles are obtained through CFD simulation. Then, the rudder aerodynamic net load data is obtained according to the difference between the rudder aerodynamic load data and the 0 rudder yaw rudder aerodynamic load data. In order to facilitate subsequent analysis, the rudder aerodynamic net load data table can be formed according to the rudder aerodynamic net load data, and output in the form of three channels of pitch channel, yaw channel and roll channel. Table 2 shows the data form of the rudder aerodynamic net load data table of the pitch channel, in which Ma is the Mach number, dp is the pitch channel rudder deflection angle, beta is the sideslip angle, alpha is the attack angle, CA, CN0, CZ, C1, Cn, Cm are the axial force coefficient, normal force coefficient, lateral force coefficient, rolling moment coefficient, yaw moment coefficient and pitch moment coefficient respectively. It can be understood that the data format of the rudder aerodynamic net load data table of the yaw channel and the roll channel is consistent with that of the pitch channel, except that the parameters in the table are replaced by the yaw channel rudder deflection angle and the roll channel rudder deflection angle respectively.

[0060] Table 2

[0061]

[0062] Step S3, obtaining the substation aerodynamic load data of the whole arrow at multiple three-channel rudder deflection angles according to the sum of the rudder aerodynamic net load data and the whole arrow aerodynamic load data;

[0063] Step S4, obtaining the rocket flight state parameters and the three-channel rudder deflection angle at any time in the upstream ballistic data, and using the interpolation function to interpolate the sub-station aerodynamic load data of the whole arrow of multiple three-channel rudder deflection angles to obtain the sub-station aerodynamic load data of the whole arrow at any time;

[0064] Specifically, the substation aerodynamic load data includes an axial force coefficient of each substation and a normal force coefficient of each substation.

[0065] It should be noted that the upstream ballistic data is data input by upstream professionals (upstream departments) and is a known quantity.

[0066] Step S5, obtaining the rocket flight characteristic parameters at any moment in the upstream ballistic data, obtaining the flight load of each substation at any moment according to the rocket flight characteristic parameters at any moment and the substation aerodynamic load data of the whole arrow at any moment, and obtaining the equivalent load of each substation at any moment according to the flight load of each substation at any moment.

[0067] Specifically, the rocket's flight characteristic parameters include the total rocket mass, altitude, dynamic pressure, thrust, overload, etc. The flight load includes axial force, bending moment and shear force, and the equivalent load includes equivalent axial pressure and equivalent axial tension.

[0068] Among them, the axial force, bending moment and shear force are calculated according to the following formula:

[0069]

[0070]

[0071]

[0072] Where, T n is the axial force of the nth substation, M n is the bending moment of the nth substation, Q n is the shear force of the nth substation, Q (i-1) is the shear force of the i-1th substation, CA i is the axial force coefficient of the ith substation, CN i is the normal force coefficient of the ith substation, CN is the sum of the normal force coefficients of all substations, M is the total arrow mass, N x For overload, m i is the station mass of the ith substation, q is the dynamic pressure, s is the reference area, g is the gravitational acceleration, x T is the center of mass of the whole arrow, x i is the centroid position of the ith substation, x i-1 is the centroid position of the i-1th substation, x cp is the pneumatic pressure center position, J z is the moment of inertia of the ith substation.

[0073] Calculate the equivalent axial pressure F according to the following formula eq1 and equivalent axial pull F eq2 ,

[0074]

[0075]

[0076] In the formula, F eq1 is the equivalent axial pressure, F eq2 is the equivalent axial pull, and D is the cabin diameter of the nth substation.

[0077] Furthermore, the axial force, bending moment and shear force can be grouped according to the substations, and the maximum equivalent axial pressure, axial tension and corresponding time of the cabin section of each substation during the entire flight can be selected, and then the selected maximum load point can be passed to the structural department for finite element calculation. Figure 2 As shown in the figure, it is a curve of the axial force of the whole arrow at different times obtained by using the method for calculating the flight load of the launch vehicle along the trajectory provided by the embodiment of the present application, wherein the horizontal axis x / Lref is the ratio of the x coordinate of each substation to the reference length Lref, and Lref is the length of the whole arrow. The vertical axis T / Tref is the ratio of the axial force T of each substation to the reference axial force Tref, and Tref is the maximum axial force. Figure 3 As shown in FIG. 1 , it is a curve diagram of the maximum axial force of a substation compartment obtained by using the method for calculating the flight load of a launch vehicle along a trajectory provided in an embodiment of the present application. ref is the time t and the reference time t ref The ratio of t ref The time from time 0 to rocket separation is taken. The vertical axis T / Tref is the ratio of the maximum axial force T of a substation compartment to the reference axial force Tref, where Tref takes the maximum axial force.

[0078] The above article introduces the calculation method of the flight load of a single trajectory. In the actual model development process, it is often necessary to analyze the load conditions under different launch sites, wind fields, orbital inclinations, orbital altitudes, etc. It is necessary to compare the loads under multiple trajectories and select the maximum load as the design load. The specific implementation method is as follows:

[0079] 1. Determine the number of each trajectory according to the launch site, orbital altitude, and orbital inclination. For example, the first numbers 1 to 4 refer to the Jiuquan, Taiyuan, Xichang, and Wenchang launch sites, respectively; the second numbers 1 to 4 refer to 30°, 40°, 55°, and SSO orbital inclinations, respectively; and the third numbers 1 to 7 refer to 500km, 600km, 700km, 800km, 900km, 1000km, and 1100km orbital altitudes, respectively. This forms trajectory .dat files with file names such as "141, 321, 427, ..., ".

[0080] 2. Since different launch sites, orbital altitudes, and orbital inclinations correspond to different satellite masses, this will also affect the quality substation. Therefore, a data table with a one-to-one correspondence between trajectory numbers and satellite masses is established, and the satellite mass is automatically updated using a program.

[0081] 3. Use the loop to calculate the flight load under each trajectory in turn, and calculate the maximum load table of the substation compartment corresponding to the output of one trajectory, as shown in Table 3.

[0082] Table 3

[0083]

[0084]

[0085]

[0086] Compare the loads of multiple calculated trajectories, select the maximum load, and output the corresponding trajectory number, time, load result and other data.

[0087] Therefore, the present application can quickly calculate the maximum load of the compartment of each substation of a single trajectory, and also has the function of calculating the loads of multiple trajectories and screening the maximum load. The flight load calculation method provided in the present application can be combined with the collaborative design platform to achieve rapid iterative design of launch vehicles.

[0088] Based on the same inventive concept, Figure 4 As shown, the embodiment of the present application also provides a device for calculating the flight load of a launch vehicle along a trajectory, comprising:

[0089] An acquisition unit 10 is used to acquire full-arrow aerodynamic load data and 0-rudder-deflection aerodynamic load data corresponding to a plurality of rocket flight state parameters when the rocket is under a 0-rudder-deflection condition;

[0090] The first calculation unit 20 is used to obtain rudder aerodynamic load data corresponding to multiple rocket flight state parameters when the rocket is under multiple three-channel rudder deflection angle conditions; the first calculation unit 20 is also used to obtain rudder aerodynamic net load data according to the difference between the rudder aerodynamic load data and the 0 rudder deflection rudder aerodynamic load data;

[0091] A second calculation unit 30, the second calculation unit 30 is used to obtain the sub-station aerodynamic load data of the whole arrow at multiple three-channel rudder deflection angles according to the sum of the rudder aerodynamic net load data and the whole arrow aerodynamic load data;

[0092] The third calculation unit 40 is used to obtain the rocket flight state parameters and the three-channel rudder deflection angle at any time in the upstream ballistic data, and interpolate the sub-station aerodynamic load data of the whole arrow of multiple three-channel rudder deflection angles by using an interpolation function to obtain the sub-station aerodynamic load data of the whole arrow at any time;

[0093] The fourth calculation unit 50 is used to obtain the rocket flight characteristic parameters at any moment in the upstream ballistic data, obtain the flight load of each substation at any moment according to the rocket flight characteristic parameters at any moment and the substation aerodynamic load data of the whole arrow at any moment, and obtain the equivalent load of each substation at any moment according to the flight load of each substation at any moment.

[0094] In some embodiments, the rocket flight state parameters include the rocket's Mach number, angle of attack and sideslip angle, and the full arrow aerodynamic load data include the rocket's starting point coordinates, ending point coordinates, axial force coefficient, normal force coefficient, lateral force coefficient, rolling moment coefficient, yaw moment coefficient and pitch moment coefficient.

[0095] In some embodiments, the acquisition unit 10 is specifically used to obtain full-arrow aerodynamic load data and 0 rudder deflection aerodynamic load data at multiple Mach numbers, multiple angles of attack, and multiple sideslip angles when the rocket is under 0 rudder deflection conditions through computational fluid dynamics simulation.

[0096] In some embodiments, the three-channel rudder deflection angle includes the pitch channel rudder deflection angle, yaw channel rudder deflection angle, and roll channel rudder deflection angle of the rocket, and the rudder aerodynamic net load data includes the axial force coefficient, normal force coefficient, lateral force coefficient, rolling moment coefficient, yaw moment coefficient, and pitch moment coefficient of the rocket.

[0097] The first calculation unit 20 is specifically used for:

[0098] The rudder aerodynamic load data at multiple Mach numbers, multiple angles of attack and multiple sideslip angles under the conditions of multiple pitch channel rudder deflection angles, multiple yaw channel rudder deflection angles and multiple roll channel rudder deflection angles are obtained through computational fluid dynamics simulation.

[0099] In some embodiments, the substation aerodynamic load data includes an axial force coefficient for each substation and a normal force coefficient for each substation.

[0100] In some embodiments, the rocket flight characteristic parameters include total rocket mass, altitude, dynamic pressure, thrust, and overload; the flight load includes axial force, bending moment, and shear force; and the equivalent load includes equivalent axial pressure and equivalent axial tension.

[0101] In some embodiments, the fourth calculation unit 50 is specifically configured to:

[0102] Calculate the axial force, bending moment and shear force according to the following formula;

[0103]

[0104]

[0105]

[0106] Where, T n is the axial force of the nth substation, M n is the bending moment of the nth substation, Q n is the shear force of the nth substation, Q (i-1) is the shear force of the i-1th substation, CA i is the axial force coefficient of the ith substation, CN i is the normal force coefficient of the ith substation, CN is the sum of the normal force coefficients of all substations, M is the total arrow mass, N x For overload, m i is the station mass of the ith substation, q is the dynamic pressure, s is the reference area, g is the gravitational acceleration, x T is the center of mass of the whole arrow, x i is the centroid position of the ith substation, x i-1 is the centroid position of the i-1th substation, x cp is the pneumatic pressure center position, J z is the moment of inertia of the ith substation.

[0107] Calculate the equivalent axial pressure F according to the following formula eq1 and equivalent axial pull F eq2 ,

[0108]

[0109]

[0110] In the formula, F eq1 is the equivalent axial pressure, F eq2 is the equivalent axial pull, and D is the cabin diameter of the nth substation.

[0111] In summary, the present application provides a method and device for calculating the flight load of a launch vehicle along a trajectory. The method first obtains aerodynamic load data under different states, then uses an interpolation function to obtain the aerodynamic load data of all substations at any moment, and then calculates the flight load of each substation of the rocket at any moment and the equivalent load of each substation at any moment according to the rocket flight characteristic parameters in the upstream ballistic data and the aerodynamic load data of all substations. In this way, the maximum load of each substation compartment of the trajectory can be quickly calculated, and the load change characteristics of each substation compartment during the whole flight process can be obtained, and then the maximum load of each substation compartment can be screened out. The load result obtained in this way does not have the problem of missing the maximum load state, which can greatly reduce the design risk.

[0112] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the embodiments disclosed herein. The present application is intended to cover any variations, uses or adaptations of the present application, which follow the general principles of the present application and include common knowledge or customary techniques in the art that are not disclosed in the present application. It should be understood that the present application is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A method for calculating the flight load of a launch vehicle along a trajectory, characterized in that: include: Obtaining the full-arrow aerodynamic load data and the 0-rudder-deflection aerodynamic load data corresponding to multiple rocket flight state parameters when the rocket is under the condition of 0-rudder-deflection; Acquire rudder aerodynamic load data corresponding to a plurality of rocket flight state parameters when the rocket is under a plurality of three-channel rudder deflection angle conditions, and obtain rudder aerodynamic net load data according to the difference between the rudder aerodynamic load data and the 0 rudder deflection rudder aerodynamic load data; According to the sum of the rudder aerodynamic net load data and the full arrow aerodynamic load data, obtaining the full arrow aerodynamic load data of multiple substations at three-channel rudder deflection angles; Obtain the rocket flight state parameters and the three-channel rudder deflection angle at any time in the upstream ballistic data, and interpolate the sub-station aerodynamic load data of the whole arrow of the multiple three-channel rudder deflection angles using an interpolation function to obtain the sub-station aerodynamic load data of the whole arrow at any time; Acquire the rocket flight characteristic parameters at any moment in the upstream ballistic data, obtain the flight load of each substation at any moment based on the rocket flight characteristic parameters at any moment and the substation aerodynamic load data of the whole arrow at any moment, and obtain the equivalent load of each substation at any moment based on the flight load of each substation at any moment.

2. The method for calculating the flight load of a launch vehicle along a trajectory according to claim 1, characterized in that: The rocket flight state parameters include the rocket's Mach number, angle of attack and sideslip angle, and the full-arrow aerodynamic load data include the rocket's starting point coordinates, end point coordinates, axial force coefficient, normal force coefficient, lateral force coefficient, rolling moment coefficient, yaw moment coefficient and pitch moment coefficient.

3. The method for calculating the flight load of a launch vehicle along a trajectory according to claim 2, characterized in that: The method of obtaining full-arrow aerodynamic load data and 0-rudder-off-rudder aerodynamic load data corresponding to multiple rocket flight state parameters when the rocket is under the condition of 0-rudder-off-rudder comprises: obtaining full-arrow aerodynamic load data and 0-rudder-off-rudder aerodynamic load data for multiple Mach numbers, multiple angles of attack, and multiple sideslip angles when the rocket is under the condition of 0-rudder-off-rudder through computational fluid dynamics simulation.

4. The method for calculating the flight load of a launch vehicle along a trajectory according to claim 1, characterized in that: The three-channel rudder deflection angle includes the pitch channel rudder deflection angle, yaw channel rudder deflection angle, and roll channel rudder deflection angle of the rocket, and the rudder aerodynamic net load data includes the axial force coefficient, normal force coefficient, lateral force coefficient, rolling moment coefficient, yaw moment coefficient, and pitch moment coefficient of the rocket.

5. The method for calculating the flight load of a launch vehicle along a trajectory according to claim 4, characterized in that: The obtaining of rudder aerodynamic load data corresponding to a plurality of rocket flight state parameters under a plurality of three-channel rudder deflection angle conditions of the rocket comprises: The rudder aerodynamic load data at multiple Mach numbers, multiple angles of attack and multiple sideslip angles under the conditions of multiple pitch channel rudder deflection angles, multiple yaw channel rudder deflection angles and multiple roll channel rudder deflection angles are obtained through computational fluid dynamics simulation.

6. The method for calculating the flight load of a launch vehicle along a trajectory according to claim 1, characterized in that: The substation aerodynamic load data includes an axial force coefficient of each substation and a normal force coefficient of each substation.

7. The method for calculating the flight load of a launch vehicle along a trajectory according to claim 6, characterized in that: The rocket flight characteristic parameters include the total rocket mass, altitude, dynamic pressure, thrust, and overload; the flight load includes axial force, bending moment, and shear force; and the equivalent load includes equivalent axial pressure and equivalent axial tension.

8. The method for calculating the flight load of a launch vehicle along a trajectory according to claim 7, characterized in that: The step of obtaining the flight load of each substation at any time according to the rocket flight characteristic parameters at any time and the substation aerodynamic load data of the whole rocket at any time comprises: Calculate the axial force, bending moment and shear force according to the following formula; Where, T n is the axial force of the nth substation, M n is the bending moment of the nth substation, Q n is the shear force of the nth substation, Q (i-1) is the shear force of the i-1th substation, CA i is the axial force coefficient of the ith substation, CN i is the normal force coefficient of the ith substation, CN is the sum of the normal force coefficients of all substations, M is the total arrow mass, N x For overload, m i is the station mass of the ith substation, q is the dynamic pressure, s is the reference area, g is the gravitational acceleration, x T is the center of mass of the whole arrow, x i is the centroid position of the ith substation, x i-1 is the centroid position of the i-1th substation, x cp is the pneumatic pressure center position, J z is the moment of inertia of the ith substation.

9. The method for calculating the flight load of a launch vehicle along a trajectory according to claim 8, characterized in that: The obtaining the equivalent load of each substation at any time according to the flight load of each substation at any time comprises: Calculate the equivalent axial pressure F according to the following formula eq1 and equivalent axial pull F eq2 , In the formula, F eq1 is the equivalent axial pressure, F eq2 is the equivalent axial pull, and D is the cabin diameter of the nth substation.

10. A device for calculating the flight load of a launch vehicle along a trajectory, characterized in that: include: An acquisition unit, the acquisition unit is used to acquire full-arrow aerodynamic load data and 0-rudder deflection aerodynamic load data corresponding to a plurality of rocket flight state parameters when the rocket is under a 0-rudder deflection condition; A first calculation unit, the first calculation unit is used to obtain rudder aerodynamic load data corresponding to a plurality of rocket flight state parameters when the rocket is under a plurality of three-channel rudder deflection angle conditions; the first calculation unit is also used to obtain rudder aerodynamic net load data according to the difference between the rudder aerodynamic load data and the 0 rudder deflection rudder aerodynamic load data; A second calculation unit, the second calculation unit is used to obtain the sub-station aerodynamic load data of the whole arrow at multiple three-channel rudder deflection angles according to the sum of the rudder aerodynamic net load data and the whole arrow aerodynamic load data; a third calculation unit, the third calculation unit being used to obtain the rocket flight state parameters and the three-channel rudder deflection angle at any moment in the upstream ballistic data, and to interpolate the sub-station aerodynamic load data of the whole arrow of the plurality of three-channel rudder deflection angles by using an interpolation function to obtain the sub-station aerodynamic load data of the whole arrow at any moment; A fourth calculation unit, the fourth calculation unit is used to obtain the rocket flight characteristic parameters at any moment in the upstream ballistic data, obtain the flight load of each substation at any moment according to the rocket flight characteristic parameters at any moment and the substation aerodynamic load data of the whole arrow at any moment, and obtain the equivalent load of each substation at any moment according to the flight load of each substation at any moment.

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