CN113609591A - Defect tolerance-oriented reinforced cylinder shell rapid optimization design method - Google Patents
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Abstract
A quick optimization design method for a reinforcement cylinder shell facing defect tolerance belongs to the technical field of design of main bearing members of aerospace structures. The method comprises the following steps: 1) establishing an initial design finite element model of the reinforced cylinder shell, and carrying out defect sensitivity analysis based on nonlinear explicit post-flexion analysis; 2) determining a rigidity reduction relation function, and establishing an incomplete reduction rigidity buckling analysis model of the reinforced cylinder shell structure; 3) developing a reinforcement cylinder shell optimization design facing defect tolerance based on an incomplete reduction stiffness method; 4) and carrying out bearing analysis and precision verification on the imperfect model of the optimization result. The coupling relation between the structural design and the ultimate bearing and the defect sensitivity is fully considered, and the refinement and lightweight design of the aerospace cylinder shell structure is realized by simultaneously improving the theoretical bearing and the defect resistance of the structure; the quick optimization design of the aerospace reinforced cylinder shell structure for defect tolerance can be realized, and the problems of fine complex thin-wall structure and high light design and calculation cost in a carrier rocket are solved.
Description
Technical Field
The invention belongs to the technical field of design of main bearing members of aerospace structures, and relates to a defect tolerance-oriented quick optimization design method for a reinforced cylinder shell.
Technical Field
The thin-wall cylinder shell structure has high specific stiffness and high specific strength, so that the thin-wall cylinder shell structure is widely applied to main bearing members of space equipment such as a carrier rocket and the like. In the rocket launching process, the thin-wall cylinder shell structure bears huge axial pressure load due to overload, and buckling instability is easy to occur, so that the structure fails. Therefore, the ultimate bearing capacity of the thin-wall cylinder shell structure under the axial compression working condition is a key assessment index in the design process of space flight structures such as a carrier rocket. However, the buckling load of the cylindrical shell structure shows strong defect sensitivity, even a slight geometric defect can cause great reduction of the ultimate bearing capacity, and the defect cannot be avoided in the processes of processing, transportation, assembly and the like, so the influence of the defect on the ultimate bearing capacity must be considered in the design process of the aerospace thin-wall cylindrical shell structure.
In the traditional design process of the cartridge shell structure, the critical instability load of the perfect structure is multiplied by a more conservative fixed reduction factor to be used as the design load. Namely, the essence of the method is that the perfect structural bearing capacity is still used as the design load, the influence of the change of the design of the drum shell structure on the defect sensitivity is neglected, the safety margin is increased by using a lower reduction factor to ensure the safety and the reliability of the structure, and the structure is certainly overweight. Particularly, under the requirement of a new generation of large-diameter carrier rocket in China on cross-over improvement of carrying capacity, the diameter and the quality of the rocket body structure are greatly improved, the equivalent thickness of the aerospace composite thin-wall cylinder shell is relatively thinned due to the requirement of light structure, and the defect sensitivity problem is more prominent.
Therefore, in order to fully excavate the lightweight design space of the aerospace cylinder shell structure and realize the active weight reduction design of the aerospace cylinder shell, the design of the cylinder shell structure facing defect tolerance needs to be developed, namely, the coupling relation between the structural design and the critical instability load and the structural defect sensitivity is considered in the design process, the buckling load and the defect resistance of the structure are synchronously improved, the design of the cylinder shell structure with the maximum design load under the given mass constraint is obtained, and the refinement and lightweight design of the cylinder shell structure are realized on the premise of ensuring the safety and reliability of the aerospace structure. In the process of optimization design of the cylinder shell structure, in order to analyze and predict the ultimate bearing capacity of the imperfect cylinder shell structure containing defects with higher precision, post-buckling bearing analysis based on explicit dynamics is required. However, for an aerospace complex thin-wall cylindrical shell structure containing abundant structural detail characteristics such as ribs, single bearing analysis considering defect sensitivity is extremely time-consuming, and the calculation cost required by optimization is more unacceptable.
In summary, there is a need to establish a defect tolerance-oriented rapid optimization design method for a reinforcement shell, so as to develop a defect tolerance-oriented aerospace reinforcement shell structure design with an acceptable low computation cost, and implement a refined and lightweight design for a aerospace owner load-bearing shell structure.
Disclosure of Invention
The invention mainly solves the problem of high calculation cost caused by time consumption of nonlinear explicit post-flexion analysis in the optimization process of a defect-sensitive reinforced cylinder shell structure, and provides a defect-tolerance-oriented space reinforced cylinder shell rapid optimization design method. By using an Incomplete Reduced Stiffness Method (iRSM), a limit bearing rapid analysis low-fidelity model of a defected imperfect shell structure is established, time-consuming nonlinear explicit post-buckling analysis is replaced, and defect tolerance-oriented reinforcement shell optimization design is performed, so that a reinforcement shell structure design with maximum design load under the influence of defects is relatively and rapidly provided for space equipment such as a launch vehicle and the like under a certain mass constraint condition.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a quick optimization design method for a reinforcement cylinder shell facing defect tolerance comprises the following steps:
the method comprises the steps of firstly, establishing a geometric perfect finite element model of an initial design of a reinforced cylinder shell structure according to given parameters of the reinforced cylinder shell structure, selecting geometric defects in a specific form, introducing corresponding defect distribution data into the perfect cylinder shell finite element numerical model, establishing a non-perfect cylinder shell finite element numerical model containing the defects, and calculating the ultimate bearing capacity of the non-perfect reinforced cylinder shell structure by using nonlinear post-buckling analysis algorithms such as an arc length method and explicit dynamics to serve as design loads.
And secondly, according to the geometric defect form selected in the first step and the adopted defect distribution data, taking the design load calculated by nonlinear post-buckling analysis such as an arc length method and explicit dynamics as reference data, and establishing a buckling analysis model of the incomplete buckling stiffness of the reinforced cylinder shell in a given geometric defect form by adopting an incomplete buckling stiffness method, so as to realize the ultimate bearing rapid analysis of the defected incomplete reinforced cylinder shell structure.
The incomplete reduction stiffness method is established on the basis of a linear buckling system, and the specific technical process is as follows:
firstly, establishing a linear buckling analysis system of a geometric perfect finite element model in the first step, and acquiring a geometric stiffness matrix K of the systemG. Then, according to the geometric defect distribution data and the grid information of the finite element model, the defect amplitude value and the unit defect level value of each node are calculated. Determining a stiffness reduction relation function on the basis, establishing a mapping relation between geometric defects and unit membrane stiffness to accurately determine stiffness components of all units, calculating a stiffness matrix and assembling of each unit to obtain a total stiffness matrix of an incomplete reduction stiffness buckling system, and finally establishing an incomplete reduction stiffness buckling analysis system of an incomplete reinforcement cylinder shell structure, wherein the formula is as follows:
{(∑fKi em+Kb)+λ”KG}Φ”＝0 (1)
wherein f is a decreasing relation function between defect level and film stiffness component, KemIs a matrix of membrane stiffness of cells, KbIs a flexural rigidity matrix of the structure, KGIs a geometric rigidity matrix of the structure, i is the number of units, and lambda 'and phi' are respectively the buckling load and the buckling mode of the incomplete reduction rigidity model. By solving the incomplete reduction rigidity buckling analysis system, the ultimate bearing capacity of the imperfect reinforcement cylinder shell structure containing defects can be obtained, and low-fidelity rapid analysis of the imperfect reinforcement cylinder shell is completed.
Therefore, as long as the reduction relation function of the geometric structure defects and the membrane rigidity components of the reinforced cylinder shell is determined, the bearing capacity of the imperfect cylinder shell structure under the given geometric defect form and distribution can be rapidly analyzed under a linear buckling system.
And thirdly, using the buckling analysis model of incomplete folding and reducing rigidity of the reinforced cylinder shell built in the second step to perform low-fidelity rapid analysis on the bearing capacity of the reinforced cylinder shell structure containing defects and incomplete folding, replacing time-consuming nonlinear post-buckling analysis of an arc length method, explicit dynamics and the like, using an optimization algorithm to perform optimization design on the reinforced cylinder shell structure facing defect tolerance, and improving the ultimate bearing capacity of the reinforced cylinder shell structure containing defects by adjusting design variables such as skin thickness, rib height, rib thickness, rib layout parameters and the like, so as to realize the maximized design of the design load of the reinforced cylinder shell structure under given quality constraint.
And fourthly, carrying out limit bearing analysis of the imperfect model containing the defects and precision verification of the incomplete reduction stiffness method on the optimization design result obtained in the third step by using nonlinear post-buckling analysis such as an arc length method and explicit dynamics. And calculating the relative error of the incomplete reduction stiffness method by taking the calculation result of the nonlinear post-buckling algorithm as a reference, if the accuracy meets the requirement (the accuracy requirement needs to be specifically given by a user, and the error is generally not more than 10%), obtaining the final design of the reinforcement cylinder shell, if the accuracy does not meet the analysis accuracy requirement, supplementing the optimization result into the reference data in the second step, returning to the second step, updating the stiffness reduction relation function, and repeating the defect tolerance-oriented reinforcement cylinder shell optimization design in the third step until the accuracy requirement is met. Therefore, the quick optimization design of the reinforcement cylinder shell facing defect tolerance is completed.
Further, the geometric defects described in the first step include a plurality of geometric defect forms of real or assumed forms such as measured defects, modal defects, pit defects, and the like.
Further, the method for determining the reduction relation function in the second step includes: the method for solving undetermined parameters by matching optimization of the given function form, data analysis, function fitting, artificial intelligence, deep learning and the like.
Further, the optimization method in the third step includes optimization algorithms such as a genetic algorithm, an ant colony algorithm, a particle swarm algorithm, a sequence quadratic programming and the like, and optimization strategies such as agent model optimization, continuous distribution type optimization, hybrid optimization and the like.
The invention has the beneficial effects that:
in the structural design of the aerospace cylinder shell, the coupling relation between the structural design and the ultimate bearing and the defect sensitivity is fully considered, and the refinement and lightweight design of the aerospace cylinder shell structure is realized by simultaneously improving the theoretical bearing and defect resistance of the structure. And a bearing rapid analysis model of the imperfect reinforcement cylinder shell containing the defects is established based on an incomplete reduction stiffness method, time-consuming nonlinear explicit post-buckling analysis is replaced for optimization design, the defect tolerance-oriented rapid optimization design of the aerospace reinforcement cylinder shell structure is realized, the problems of refinement of a complex thin-wall structure and high calculation cost of lightweight design in a carrier rocket are solved, and a design method, an optimization tool and guidance can be provided for the design of a main bearing cylinder shell structure in a new generation carrier rocket.
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Fig. 1 is a flowchart of an implementation of a defect tolerance-oriented stiffened shell rapid optimization design method provided by the invention;
FIG. 2 is a graph illustrating the convergence of the geometric defect sensitivity analysis of the initial design of the orthorhombic grid stiffened shell according to the example of the present invention;
FIG. 3 is a diagram of an iterative optimization of orthorhombic grid stiffened shell multi-island inheritance provided by an example of the present invention;
Detailed Description
In order to make the process problems solved by the present invention, the process schemes adopted and the process effects achieved more clear, the present invention will be further described in detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some but not all of the relevant aspects of the present invention are shown in the drawings.
Fig. 1 is a flowchart illustrating an implementation of a defect tolerance-oriented stiffened shell design method according to an embodiment of the present invention. As shown in fig. 1, a method for quickly and optimally designing a reinforced cylinder casing facing defect tolerance, provided by the embodiment of the present invention, includes: 1) establishing an initial design finite element model of the reinforced cylinder shell, and carrying out defect sensitivity analysis based on nonlinear explicit post-flexion analysis; 2) determining a rigidity reduction relation function, and establishing an incomplete reduction rigidity buckling analysis model of the reinforced cylinder shell structure; 3) developing a reinforcement cylinder shell optimization design facing defect tolerance based on an incomplete reduction stiffness method; 4) and carrying out bearing analysis and precision verification on the imperfect model of the optimization result. The method comprises the following specific steps:
example (b): optimized design of orthorhombic grid reinforced cylinder shell for defect tolerance
Firstly, establishing a finite element model of an initial design of an orthorhombic grid reinforced cylinder shell structure. Wherein, the radius of the reinforced cylinder shell is 800mm, and the height is 1000 mm. The specific dimensional parameters of the initial design include: the skin thickness ts is 1.6mm, the rib thickness tr is 2.5mm, the rib height hr is 11.9mm, the number NC of annular ribs is 17, and the number NA of longitudinal ribs is 138. The material is 2A14 aluminum alloy, the elastic modulus is 76169MPa, and the density is 2700kg/m 3. The load conditions and boundary conditions in the finite element model analysis were as follows: the lower end of the cylinder shell is under the condition of a fixed support boundary, a reference point is established at the circle center of the upper end surface of the cylinder shell and is completely coupled with the upper end surface, all other degrees of freedom of the coupling point except axial displacement are fixed, and axial pressure load is applied to the reference point.
Next, defect sensitivity analysis of the initial design of the stiffened shell structure was performed using a Single point Perturbation Load Approach (SPLA) based on geometric defects in the form of pits. Specifically, a perturbation load is first applied to the middle of the outer wall of the cartridge housing to create a geometric defect in the form of a single dimple in the cartridge housing. Then, geometric defects are introduced into a perfect finite element of the cartridge shell, and the limit bearing capacity of the imperfect cartridge shell structure is obtained based on nonlinear explicit post-buckling analysis. Subsequently, by gradually increasing the magnitude of the disturbance load, a geometric defect sensitivity analysis curve as shown in fig. 2 can be obtained. It can be seen that for the initial design of the stiffened shell, its ultimate load-carrying capacity gradually decreases and tends to converge as the perturbation load increases. And when the disturbance load is 8kN, the limit load of the structure is used as a load bearing lower limit and a design load, and the initially designed design load is 3209.3 kN.
And step two, determining a stiffness reduction relation function by taking an analysis result of the single-point disturbance load method in the step one as reference data, and establishing an incomplete reduction stiffness buckling analysis model of the reinforced cylinder shell structure. The method for solving undetermined parameters by matching optimization in a given function form is adopted to determine the defect rigidity reduction relation function, and specifically, the reduction relation function form containing undetermined parameters given by the example is as follows:
in the formula: u. ofi eRepresenting the level of geometrical defects, t, of each element of the finite-element modeliAnd kiThickness and total number of nodes, w, of the ith shell element, respectivelyijThe defect amplitude of the jth node in the cell. A and B are two undetermined parameters in the discounted stiffness function. Wherein, the parameter A controls the convergence speed of the stiffness reduction relation function, and the parameter B controls the limit of the stiffness reduction degree of the film. When the cell geometric defect level is zero, the cell membrane stiffness is not folded, and the folding degree of the membrane stiffness is monotonically increased along with the increase of the geometric defect level and gradually converges to a fixed value (1/1+ B). The membrane stiffness of the housing is not completely eliminated even if the level of geometrical defects is very large. The monotonous decreasing trend of the reduction relation function shows that the larger the defect level of the cylinder shell is, the more the membrane rigidity is reduced, and the smaller the non-perfect cylinder shell reduction factor is. In addition, the level of cell defects is normalized based on the cell thicknessIt is shown that the thinner the shell, the more sensitive it is to geometric defects at the same amplitude of geometric defects. The characteristics of the rigidity reduction relation function all accord with the sensitivity rule of the structure defect of the thin-wall cylinder shell observed in the prior experiment. Therefore, the proposed reduction relation function can describe the relation between the model membrane rigidity and the defects, and the bearing rapid analysis of the imperfect cartridge shell can be realized under the linear buckling analysis framework only by determining undetermined parameters in the reduction relation function.
And then, determining two parameters in the reduction relation function by adopting an optimization method based on the analysis result of the single-point disturbance load method, and establishing an incomplete reduction rigidity buckling analysis model of the reinforced cylinder shell structure. It should be noted that, for the reinforced cylindrical shell structure, the ribs serve to increase the bending rigidity of the whole cylindrical shell structure, so that in this example, only the film rigidity of the skin is reduced, and no treatment is performed on the rib rigidity. The optimized formula is as follows:
in the formula:
and
and (3) representing the limit bearing obtained by respectively using an incomplete reduction stiffness method and a nonlinear explicit post-buckling analysis (SPLA) based method when the disturbance load is t, and selecting an inflection point and a convergence point in the SPLA defect sensitivity analysis curve as a reference.
Two parameters of the reduction stiffness relation function obtained by optimization are respectively 51.39 and 1.30, and a defect sensitivity analysis curve can be obtained based on the stiffness reduction relation function as shown in fig. 2. It can be seen that the two defect sensitivity analysis curves are substantially coincident in the convergence section, and the design load obtained by iRSM is 3205.6kN, and compared with the nonlinear explicit post-buckling analysis result, the error is only-0.12%. The nonlinear explicit post-buckling analysis needs about 13.5 minutes, the iRSM only needs about 1 minute, and the calculation cost is only 7.41% of the nonlinear explicit post-buckling analysis, which shows that the iRSM can realize high-precision rapid analysis of the bearing capacity of the imperfect stiffened shell structure.
And thirdly, developing a reinforcement cylinder shell optimization design facing defect tolerance based on an incomplete reduction stiffness method. The method aims to improve the bearing capacity of the axial pressure limit under the action of the defect by taking the initial design quality of the reinforced cylinder shell not exceeding the original design quality as a constraint condition, and develops the optimized design of the axial pressure reinforced cylinder shell facing the defect tolerance, wherein the upper limit and the lower limit of the design variable are shown in the table 1.
For comparison, optimization was performed based on nonlinear explicit post-flexion analysis and iRSM, respectively. In addition, in order to find a global optimal solution as much as possible, the example uses a hybrid optimization strategy, namely, a multi-island genetic optimization algorithm is used firstly, and then a gradient algorithm such as sequence quadratic programming is used for carrying out optimization. Considering that the calculation cost of the nonlinear explicit post-buckling single analysis is too high, the main parameters of the multi-island genetic algorithm are set as follows: the population number is 30, the island number is 4, and the maximum genetic algebra is 10. From the iterative curve of the multi-island genetic optimization as shown in fig. 3, both optimizations have converged during the global optimization. Then, the optimal solution of the genetic algorithm is used as an initial point, and a sequence quadratic programming method is used for gradient optimization, so that the final optimization result can be obtained and is shown in table 2.
TABLE 1 ribbed case design variables Upper and lower limits
TABLE 2 optimization results for defect tolerant stiffened shell structures
And fourthly, carrying out bearing analysis and precision verification on the imperfect model of the optimization result. The optimization result based on the iRSM is 3768.3kN, and the SPLA design load is 3630.5kN and the error of the iRSM optimization result is 3.8% through verification by using nonlinear explicit post-buckling analysis, so that the analysis error requirement is met. While the SPLA design load based on the nonlinear explicit post-flexion analysis optimization results was 3672.2 kN.
It can be seen that the design loads of the two optimization results are approximate but the variable parameters are different, and because the design space of the buckling optimization problem of the cylinder shell has the characteristics of strong nonlinearity, multiple peaks and the like, a plurality of design results with similar performance but obvious differences may exist. In addition, compared with the initial design, the SPLA design loads of two defect tolerant reinforcement cylinder shell optimization design results are respectively improved by 13.12% and 14.55%, the buckling load and the defect resistance are simultaneously improved, the reinforcement cylinder shell design load is improved, the light weight level is guaranteed, and the safety margin of the cylinder shell structure is improved. Furthermore, it can be found that the design load based on iRSM optimization results is only 1.24% lower than the design load based on non-linear explicit post-flexion analysis optimization results, but it takes only about 16.67% of the latter (where a single analysis includes a time cost of modeling and meshing around 1.5 minutes). The method has the advantages that the nonlinear explicit post-buckling analysis in the optimization process is replaced by the incomplete buckling and reducing rigidity method, so that the optimization result can be stably found, the calculation cost can be reduced by over 80%, and the defect tolerant stiffened shell structure-oriented rapid optimization design is realized.
In conclusion, the defect tolerance-oriented reinforced cylinder shell rapid optimization design method can stably find an optimization result, reduce the calculation cost by more than 80%, realize the defect tolerance-oriented reinforced cylinder shell structure rapid optimization design, and provide a design method, an optimization tool and guidance for the design of a main bearing cylinder shell structure in a new generation of carrier rocket.
Finally, it should be noted that: the above examples are intended to illustrate the process scheme of the invention, but not to limit it; although the invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art will understand that: modifications of the method solutions described in the preceding embodiments, or equivalent substitutions of some or all of the method features, are possible without departing from the scope of the method solutions of the embodiments of the present invention.
Claims (5)
1. A quick optimization design method for a reinforcement cylinder shell facing defect tolerance is characterized by comprising the following steps:
firstly, establishing a geometric perfect finite element model of an initial design of a reinforced cylinder shell structure according to given parameters of the reinforced cylinder shell structure, selecting geometric defects in a specific form, introducing corresponding defect distribution data into a perfect cylinder shell finite element numerical model, establishing a non-perfect cylinder shell finite element numerical model containing defects, and calculating the ultimate bearing capacity of the non-perfect reinforced cylinder shell structure by adopting a non-linear post-buckling analysis algorithm to serve as a design load;
secondly, according to the geometric defect form selected in the first step and the adopted defect distribution data, the design load obtained in the first step is used as reference data, and an incomplete reduction rigidity analysis model of the reinforcement cylinder shell in a given geometric defect form is established by adopting an incomplete reduction rigidity method, so that the ultimate bearing rapid analysis of the defected imperfect reinforcement cylinder shell structure is realized;
the incomplete reduction stiffness method is established on the basis of a linear buckling system, and the specific technical process is as follows:
firstly, establishing a linear buckling analysis system of a geometric perfect finite element model, and acquiring a geometric stiffness matrix K of the systemG(ii) a Secondly, calculating the defect amplitude and the unit defect level value of each node according to the geometric defect distribution data and the grid information of the finite element model; determining a stiffness reduction relation function on the basis, establishing a mapping relation between geometric defects and unit membrane stiffness to accurately determine stiffness components of all units, calculating a stiffness matrix and assembling of each unit to obtain a total stiffness matrix of an incomplete reduction stiffness buckling system, and finally establishing an incomplete reduction stiffness buckling analysis system of an incomplete reinforcement cylinder shell structure, wherein the formula is as follows:
{(∑fKi em+Kb)+λ”KGphi ═ 0 (1) where f is absentReduction function of the trap level and the membrane stiffness component, KemIs a matrix of membrane stiffness of cells, KbIs a flexural rigidity matrix of the structure, KGThe method is characterized in that the method is a geometric stiffness matrix of a structure, i is the number of a unit, and lambda 'and phi' are respectively the buckling load and the buckling mode of an incomplete reduction stiffness model;
by solving the incomplete reduction rigidity buckling analysis system, the ultimate bearing capacity of the imperfect reinforcement cylinder shell structure containing defects can be obtained, and the low-fidelity rapid analysis of the imperfect reinforcement cylinder shell is completed;
thirdly, using the buckling analysis model of the incomplete folding and reducing rigidity of the reinforced cylinder shell built in the second step to perform low-fidelity rapid analysis on the bearing capacity of the reinforced cylinder shell structure containing defects and incomplete folding, performing defect-tolerant optimized design on the reinforced cylinder shell structure by using an optimization algorithm, and improving the ultimate bearing capacity of the reinforced cylinder shell structure containing defects by adjusting the skin thickness, the rib height, the rib thickness, rib layout parameters or other design variables, thereby realizing the maximized design of the design load of the reinforced cylinder shell structure under given quality constraint;
fourthly, performing limit bearing analysis of the imperfect model containing the defects and precision verification of the incomplete reduction stiffness method on the optimization design result obtained in the third step by adopting nonlinear post-buckling analysis; calculating the relative error of the incomplete reduction stiffness method by taking the calculation result of the nonlinear post-buckling algorithm as a reference, and judging whether the relative error meets the precision requirement: if the precision meets the requirement, the final design of the reinforced cylinder shell can be obtained; if the requirement of the analysis precision is not met, supplementing the optimization result into the reference data in the second step, returning to the second step, updating the stiffness reduction relation function, and re-performing the defect tolerance-oriented reinforcement cylinder shell optimization design in the third step until the requirement of the precision is met; therefore, the quick optimization design of the reinforcement cylinder shell facing defect tolerance is completed.
2. The method for rapidly and optimally designing the defect-tolerant reinforced cylinder shell according to claim 1, wherein the geometric defects in the first step comprise measured defects, modal defects, pit defects or other real or assumed geometric defect forms.
3. The method for quickly and optimally designing the defect-tolerant stiffened cylinder shell according to claim 1 or 2, wherein the reduction relation function determining method in the second step comprises the following steps: a method for solving undetermined parameters by matching optimization of a given function form, a data analysis method, a function fitting method, an artificial intelligence method and a deep learning method.
4. The method for quickly optimizing and designing the defect-tolerance-oriented reinforced cylinder shell according to claim 1 or 2, wherein the optimization method in the third step comprises optimization algorithms such as genetic algorithm, ant colony algorithm, particle swarm algorithm, sequential quadratic programming and the like, agent model optimization strategy, continuous distribution optimization strategy and hybrid optimization strategy.
5. The defect tolerance-oriented reinforced cylinder shell fast optimization design method according to claim 3, wherein the optimization method in the third step comprises optimization algorithms such as genetic algorithm, ant colony algorithm, particle swarm algorithm, sequence quadratic programming and the like, agent model optimization strategy, continuous distribution optimization strategy and hybrid optimization strategy.
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