CN102930161A - Hybrid modal indicating method based on multi-cabin spacecraft - Google Patents
Hybrid modal indicating method based on multi-cabin spacecraft Download PDFInfo
- Publication number
- CN102930161A CN102930161A CN2012104310370A CN201210431037A CN102930161A CN 102930161 A CN102930161 A CN 102930161A CN 2012104310370 A CN2012104310370 A CN 2012104310370A CN 201210431037 A CN201210431037 A CN 201210431037A CN 102930161 A CN102930161 A CN 102930161A
- Authority
- CN
- China
- Prior art keywords
- model
- modal
- analysis
- minor structure
- spacecraft
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Abstract
The invention discloses a hybrid modal indicating method based on a multi-cabin spacecraft. The method includes that step one, the multi-cabin spacecraft is divided into substructures, and each substructure is a cabin; step two, a theoretical model of one of the substructures in the step one is established, a dynamic characteristic analysis is performed, and a modal of the substructure is identified to obtain a frequency and a vibration mode of the substructure; step three, an experimental model of the substructure in the step two is established, and the dynamic characteristic experiment analysis is performed to obtain an experimental modal of the substructure; step four, the theoretical model in the step two is corrected according to the experimental modal data in the step three, so that a modal analysis result frequency of the theoretical model is identical to an experimental frequency, and the vibration mode trends are identical; step five, theoretical models of other substructures are established, and the theoretical models are corrected according to the correction result of the step four; and step six, according to the actual structure of the multi-cabin spacecraft, combination portions between cabins are established, the corrected theoretical models of the substructures are combined to obtain the overall modal analysis model of the multi-cabin spacecraft, overall modal analysis model is subjected to the modal analysis, and the modal of the multi-cabin spacecraft is indicated.
Description
Technical field
The present invention relates to a kind of predicting method based on the hybrid mode result of actual loading test data and theoretical analysis model for many cabins section spacecraft.
Background technology
Along with the widespread use in space flight and aviation and various heavy constructions field of contemporary large scale structure and labyrinth, requirement and the difficulty of structural modeling technology improved constantly.The maximization of structure has determined structural entity is carried out traditional finite element analysis computation inefficiency on the one hand; The complicacy of structure has determined that only setting up a finite element model that conforms to practical structures with slip-stick artist's experience wish realizes that property is relatively poor on the other hand.Mainly rely at present the checking of test figure for the finite element model correctness of the medium-and-large-sized labyrinth of engineering, and realize the correction of finite element model in experimental basis.
In the dynamic analysis of structure, general way is that structure is carried out discretize, sets up the discretization model of structure at present, and being about to a unlimited multivariant continuous system discrete is the system of a finite degrees of freedom, and wherein commonly used is finite element method.The method with structural separation after general structure stiffness matrix and mass matrix order higher, can bring calculated amount larger, the shortcoming that computational accuracy is lower.The widespread use of substructure method is the effective ways of labyrinth modeling and analysis, utilizes the thought of Dynamic Substructure Methods " break the whole up into parts, knot zero is for whole " can reduce the calculating order, simplifies and calculates.The method of setting up the kinetic model of large and complex structure system has theoretical modeling, Experiment Modeling and hybrid modeling, namely adopts Dynamic Substructure Methods thought to carry out modeling, i.e. decomposition-connection-comprehensive process.
When system is carried out model analysis, the analytic process that adopts is the analysis Accelerated Life at present, first model is carried out theoretical analysis, after finishing, production carries out test identification, and theoretical model revised, the drawback of doing like this is that analytical cycle is longer, the model workload is larger, can not shift to an earlier date foreseen outcome.
Summary of the invention
Technology of the present invention is dealt with problems and is: overcome the deficiencies in the prior art, provide a kind of based on many cabins section spacecraft hybrid mode predicting method, the method can be obtained reliable modal data before the spacecraft product.
Technical solution of the present invention is: based on many cabins section spacecraft hybrid mode predicting method, step is as follows:
(1) many cabins section spacecraft is divided into minor structure, each minor structure is a cabin section;
(2) to the model action specificity analysis of going forward side by side that theorizes of the some minor structures in the step 1, the mode of this minor structure of identification namely obtains frequency and the vibration shape of this minor structure;
(3) minor structure in the step (2) is set up the test model action attribute testing analysis of going forward side by side, obtain the Modal Test of this minor structure;
(4) according to the theoretical model in the Modal Test data correction step (2) in the step (3), so that the modal analysis result frequency of theoretical model is identical with test frequency, vibration shape trend is identical;
(5) to other minor structure model that theorizes, and according to the correction result in the step (4) theoretical model is revised;
(6) according to the structure of many cabins of reality section spacecraft, set up intersegmental joint portion, cabin, the theoretical model of revised each minor structure is made up, obtain the Integral modes analytical model of many cabins section spacecraft, the Integral modes analytical model is carried out model analysis, the mode of many cabins section spacecraft is shown in advance.
The present invention compared with prior art beneficial effect is: the present invention carries out hybrid modeling with complex model by minor structure by Dynamic Substructure Methods, can improve the precision that model calculates.For the large and complex structure system, adopt Dynamic Substructure Methods to carry out result's indication, can reduce test and analytical cycle, increase economic efficiency.
Description of drawings
Fig. 1 is process flow diagram of the present invention;
Fig. 2 is embodiment of the invention cabin section one-piece construction figure;
Fig. 3 is minor structure one schematic diagram of Fig. 2;
Fig. 4 is minor structure two schematic diagram of Fig. 2;
Fig. 5 is the experiment wire-frame model;
Fig. 6 is the corresponding point of selecting on the theoretical model;
Fig. 7 is the objective function convergence map
Fig. 8 is material Poisson ratio convergence map;
Fig. 9 is two kinds of thickness of shell elements convergence maps;
Figure 10 is the density of material convergence map;
Figure 11 is the mode result that indicates of the present invention and comparison diagram based on the result of nastran overall calculation.
Embodiment
Below in conjunction with drawings and Examples the present invention is elaborated, as shown in Figure 1, the present invention is based on many cabins section spacecraft hybrid mode predicting method, step is as follows:
(1) many cabins section spacecraft is divided into minor structure, each minor structure is a cabin section;
The integral body of cabin segment structure as shown in Figure 2, it is divided into two from the centre (this example only is the validity of checking modal synthesis compute mode, does not consider the division principle of minor structure), each minor structure is carried out grid with the PSHELL unit and is divided.Wherein minor structure one (Fig. 3) contains 780 unit, 840 nodes, 5040 degree of freedom; Minor structure two (Fig. 4) contains 840 unit, 920 nodes, 5400 degree of freedom.
(2) to the model action specificity analysis of going forward side by side that theorizes of the some minor structures in the step (1), the mode of this minor structure of identification namely obtains frequency and the vibration shape of this minor structure;
In this example minor structure shown in Figure 3 is carried out the theoretical modeling action specificity analysis of going forward side by side, adopt theoretical frequency and the vibration shape that obtains this minor structure of calculating of nastran, Fig. 6 is the data point of selecting on minor structure one theoretical model.
(3) minor structure in the step (2) is set up the test model action attribute testing analysis of going forward side by side, obtain the Modal Test of this minor structure;
Fig. 5 is for choosing test point on test model corresponding to data point with Fig. 6.Table 1 provides the result of experimental test and the correlative value of the calculated results.
The contrast of table 1 test figure resonant frequency and theoretic frequency crest frequency
(4) according to the theoretical model in the Modal Test data correction step (2) in the step (3), so that the modal analysis result frequency of theoretical model is identical with test frequency, vibration shape trend is identical;
Model Updating Technique compares the results and test findings exactly according to certain criterion.What therefore, Model Updating Technique at first will be considered is exactly test and the theoretical correlation analysis that calculates finite element model.
When carrying out the model correction, generally suppose empirical model than finite element model more near the time of day of structure, correlation analysis just is based on the method for evaluation test data finite element model reliability.
1, frequency domain correlation correction
The modal calculation correlation analysis is the survey frequency ω of same order relatively
aWith calculated rate ω
a, the size of the difference between them has represented degree of correlation, is often represented with following number percent:
ε
ω＝(ω
e-ω
a)/ω
a
2, modal assurance criterion (MAC)
Modal assurance criterion is exactly the degree of correlation that represents two modal vector with a number.Each MAC value is the related coefficient of a pair of calculating vibration shape and the experiment vibration shape:
Wherein,
Be i rank FEM (finite element) calculation mode, Ψ
jBe j rank Modal Test, n is the FEM (finite element) calculation rank number of mode, the rank number of mode that m obtains for test.
Always between 0 and 1, it is relevant fabulous that the MAC value equals 1 expression to the MAC value; Equal two mode wide of the marks of 0 expression.
Above dynamic model modification method is the method for commonly using, and model modification method in this paper is different from above model modification method commonly used.
In the model correction comparatively effective method be to carry out the sensitivity analysis correction, sensitivity analysis comprises Eigenvalue Sensitivity Analysis, Method For Calculating Eigenvector Sensitivity analysis, modal assurance criterion sensitivity analysis, Stiffness Matrix quality battle array basis of sensitivity analysis.
Sensitivity analysis is the important step of design parameter type finite element model correction, and accurately sensitivity analysis has considerable influence for improving to revise speed of convergence and revise precision.The purpose of sensitivity analysis is to obtain structure characteristic parameter for the partial derivative of design parameter.
The correction principle that the present invention adopts is to adopt the method for sensitivity analysis.
According to test figure, for cylindrical model, its initial finite element model is optimized correction.Adopt least square method, the constitution optimization objective function.Revising variable has four classes, is respectively: density of material, elastic modulus, Poisson ratio, thickness of shell elements.
Objective function:
Wherein A, B, C are respectively initial finite element model and the corresponding frequency exponent number of test.
This paper carries out sensitivity analysis by the DMAP language, obtains revising the convergency value of variable, thereby revises finite element model.The correction step is as follows:
1. definition design variable, the variable in this paper makeover process have material Poisson ratio, two kinds of thickness of shell elements, density of material.
Design variable is related with cell attribute (physical dimension, material behavior) 2..
3. objective definition function F (A, B, C).
4. definition constraint condition is limited in design variable in the scope that allows to change.
The specific implementation process is to add data card in the model data section, will change or add a small amount of control command in the operating conditions shed repair simultaneously.
Under the target of objective function F (A, B, C) minimum, iteration correction finite element model, the final convergence map of objective function is as shown in Figure 7.
The employing Sensitivity Analysis Method obtains, each correction variable convergence map such as Fig. 8～and shown in Figure 10, revised finite element model adopts the convergency value of respectively revising variable.
(5) to other minor structure model that theorizes, and according to the correction result in the step (4) theoretical model is revised; The revised finite element model of other minor structure adopts the convergency value of revising variable.
(6) according to the structure of many cabins of reality section spacecraft, set up intersegmental joint portion, cabin, the theoretical model of revised each minor structure is made up, obtain the Integral modes analytical model of many cabins section spacecraft, the Integral modes analytical model is carried out model analysis, the mode of many cabins section spacecraft is shown in advance.
Revised model among Fig. 3 and Fig. 4 is carried out the modal synthesis operation.For this example we mainly two lobes are breathed in the same way, quadrature two lobes are breathed, three lobes are breathed in the same way, quadrature three lobes are breathed, five kinds of vibration shapes such as vertical are as the examination object take the cabin section.
The present invention indicates integrally-built modal data and the mode of calculating block mold by the nastran theory, and table 2 provides comparing result.
The frequency computation part error is respectively shown in table 3 and table 4 before and after the model correction.
Relative difference on frequency before table 3 cylinder test frequency and the model correction
Frequency contrast after table 4 cylinder test frequency and the model correction
The mode result that Figure 11 provides the present invention indication and comparison diagram based on the result of nastran overall calculation.Wherein a, b are for adopting 8,9 first order mode figure of the inventive method analysis, and c, d are respectively and adopt formation figure corresponding to nastran overall calculation.Comprehensive above model frequency and the comparison of vibration shape result of calculation, by modal synthesis method to the calculating of cabin section mode with substantially identical to whole cabin section mode result's result of calculation based on nastran.Theory error is reduced in 2.5% after the model correction.
The unspecified part of the present invention belongs to general knowledge as well known to those skilled in the art.
Claims (1)
1. based on many cabins section spacecraft hybrid mode predicting method, it is characterized in that step is as follows:
(1) many cabins section spacecraft is divided into minor structure, each minor structure is a cabin section;
(2) to the model action specificity analysis of going forward side by side that theorizes of the some minor structures in the step 1, the mode of this minor structure of identification namely obtains frequency and the vibration shape of this minor structure;
(3) minor structure in the step (2) is set up the test model action attribute testing analysis of going forward side by side, obtain the Modal Test of this minor structure;
(4) according to the theoretical model in the Modal Test data correction step (2) in the step (3), so that the modal analysis result frequency of theoretical model is identical with test frequency, vibration shape trend is identical;
(5) to other minor structure model that theorizes, and according to the correction result in the step (4) theoretical model is revised;
(6) according to the structure of many cabins of reality section spacecraft, set up intersegmental joint portion, cabin, the theoretical model of revised each minor structure is made up, obtain the Integral modes analytical model of many cabins section spacecraft, the Integral modes analytical model is carried out model analysis, the mode of many cabins section spacecraft is shown in advance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012104310370A CN102930161A (en) | 2012-10-31 | 2012-10-31 | Hybrid modal indicating method based on multi-cabin spacecraft |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012104310370A CN102930161A (en) | 2012-10-31 | 2012-10-31 | Hybrid modal indicating method based on multi-cabin spacecraft |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102930161A true CN102930161A (en) | 2013-02-13 |
Family
ID=47644958
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012104310370A Pending CN102930161A (en) | 2012-10-31 | 2012-10-31 | Hybrid modal indicating method based on multi-cabin spacecraft |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102930161A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106649902A (en) * | 2015-10-30 | 2017-05-10 | 湖北航天技术研究院总体设计所 | Quick assessment and optimization method for inherent vibration characteristics of aircraft cabin section |
| CN107066701A (en) * | 2017-03-21 | 2017-08-18 | 北京强度环境研究所 | The model building method of dynamics experiment based on spacecraft |
| CN107704679A (en) * | 2017-09-29 | 2018-02-16 | 北京金风科创风电设备有限公司 | Correction equipment and method for direct-drive generator model |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2006097442A1 (en) * | 2005-03-15 | 2006-09-21 | Astrium Sas | Chain for measuring pyrotechnical impacts and method for qualifying said chain |
| CN101546346A (en) * | 2008-03-27 | 2009-09-30 | 方辉 | Correction method for finite element model with linear period grid sandwich structure |
-
2012
- 2012-10-31 CN CN2012104310370A patent/CN102930161A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2006097442A1 (en) * | 2005-03-15 | 2006-09-21 | Astrium Sas | Chain for measuring pyrotechnical impacts and method for qualifying said chain |
| CN101546346A (en) * | 2008-03-27 | 2009-09-30 | 方辉 | Correction method for finite element model with linear period grid sandwich structure |
Non-Patent Citations (7)
| Title |
|---|
| 徐波: "某重型车驱动桥壳的静动态特性分析与评价", 《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》 * |
| 李效法: "基于灵敏度分析的模型修正研究及其实现", 《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》 * |
| 李效法: "基于灵敏度分析的模型修正研究及其实现", 《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》, 15 December 2007 (2007-12-15), pages 028 - 10 * |
| 申波: "复合材料对称层合板特征问题的灵敏度分析", 《贵州工业大学学报》 * |
| 董小军: "基于灵敏度分析的结构动力模型修正及损伤识别研究", 《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》 * |
| 董小军: "基于灵敏度分析的结构动力模型修正及损伤识别研究", 《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》, no. 11, 15 November 2009 (2009-11-15), pages 038 - 151 * |
| 邱吉宝 等: "运载火箭结构动力分析的一些新技术 第二部分：运载火箭结构动力学分析", 《导弹与航天运载技术》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106649902A (en) * | 2015-10-30 | 2017-05-10 | 湖北航天技术研究院总体设计所 | Quick assessment and optimization method for inherent vibration characteristics of aircraft cabin section |
| CN106649902B (en) * | 2015-10-30 | 2019-08-23 | 湖北航天技术研究院总体设计所 | A kind of aircraft bay section natural vibration characteristic rapid evaluation and optimization method |
| CN107066701A (en) * | 2017-03-21 | 2017-08-18 | 北京强度环境研究所 | The model building method of dynamics experiment based on spacecraft |
| CN107704679A (en) * | 2017-09-29 | 2018-02-16 | 北京金风科创风电设备有限公司 | Correction equipment and method for direct-drive generator model |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Potsdam et al. | Rotor airloads prediction using loose aerodynamic/structural coupling | |
| CN108446445B (en) | Composite material wing optimization design method based on aerodynamic reduced order model | |
| LeDoux et al. | Study based on the AIAA aerodynamic design optimization discussion group test cases | |
| Mian et al. | Numerical investigation of structural geometric nonlinearity effect in high-aspect-ratio wing using CFD/CSD coupled approach | |
| CN105843073A (en) | Method for analyzing wing structure aero-elasticity stability based on aerodynamic force uncertain order reduction | |
| Lyu et al. | RANS-based aerodynamic shape optimization investigations of the common research model wing | |
| CN108595728A (en) | A kind of laying Equivalent finite element model construction method of cellular material | |
| Peng et al. | Numerical investigation of the effects of structural geometric and material nonlinearities on limit-cycle oscillation of a cropped delta wing | |
| Lupp et al. | A gradient-based flutter constraint including geometrically nonlinear deformations | |
| CN109241559A (en) | A kind of composite material elastic parameter recognition methods based on minor structure | |
| CN110069822A (en) | A kind of sensor arrangement method of blade dynamic strain measure | |
| CN102930161A (en) | Hybrid modal indicating method based on multi-cabin spacecraft | |
| CN102880804A (en) | Aircraft wing rib dynamics determination method based on formation superposition method | |
| Nigam et al. | A toolset for creation of multi-fidelity probabilistic aerodynamic databases | |
| CN109977467A (en) | A kind of wing structure Reliability Sensitivity Method | |
| Loseille et al. | Anisotropic adaptive simulations in aerodynamics | |
| Sun et al. | Two-grid domain decomposition methods for the coupled Stokes–Darcy system | |
| Aumann et al. | MEGAFLOW: Parallel complete aircraft CFD | |
| CN108595893A (en) | A kind of three-dimensional mechanical Modal Analysis analogy method based on three layers of pretreatment | |
| Yaofei et al. | Cognition behavior model for air combat based on reinforcement learning | |
| Mundis et al. | An efficient flexible GMRES solver for the fully-coupled time-spectral aeroelastic system | |
| Neumann et al. | Steady and unsteady aeroelastic simulations of the HIRENASD wind tunnel experiment | |
| Stanford et al. | Uncertainty Quantification of the Fun3d-Predicted Nasa Crm Flutter Boundary | |
| CN104008234A (en) | Method for correcting closely spaced mode model with damping structure | |
| Stanford et al. | Uncertainty quantification of the FUN3D-predicted flutter boundary on the NASA CRM |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20130213 |