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1.
飞机风挡结构抗鸟撞一体化设计技术研究   总被引:14,自引:1,他引:13  
结合大型非线性有限元分析软件,实践了飞机风挡结构由初步设计、数值仿真以及实验验证的一体化设计过程,建立了适于风挡结构材料的非线性黏弹性本构计算接口程序,对合理选取单元类型、材料模型、边界条件影响以及试验设计等工作细节进行了深入研究,通过实验与仿真计算结果的对比,验证了数值仿真计算模型的精度.为飞机风挡的抗鸟撞结构设计-数值仿真-实验验证一体化技术提供了支持论证.  相似文献   

2.
重点介绍了基于几何非线性和总体-局部(GLOBAL-LOCAL)求解策略的进气道结构强度仿真分析技术,以此技术建立先进的进气道结构强度设计方法。该方法精度高,工程实用性强。该方法对现代歼击机进气道结构设计能够大幅度提高进气道结构强度品质,降低设计成本,提高设计一次成功率。给出了应用实例。  相似文献   

3.
高性能多路脉冲信号采集器在SINS中的应用及其CPLD实现   总被引:5,自引:0,他引:5  
提出了用于解决SINS数据采集问题的高性能多路脉冲信号采集器的设计目标,讨论了用CPLD实现该类脉冲采集器的优点并讨论了具体的设计方法。仿真设计与实测表明:采用CPLD设计的多路脉冲信号采集器能对多路脉冲信号进行严格的连续,同步采集。  相似文献   

4.
SMA阻尼器的阻尼特性分析及器件设计方法   总被引:4,自引:0,他引:4  
提出了SMA中心引线型阻尼器的力学计算模型,以Brinson本构模型为理论依据建立了阻尼器的阻尼特性分析理论及器件设计方法;利用MATLAB编制的仿真软件进行了实例仿真。结果表明SMA阻尼器具有明显的阻尼特性,加上其耐久性和免维护性,适合用于土木工程的结构振动被动控制。  相似文献   

5.
流程自动化技术因其能够将设计人员从繁重单调的建模工作中解放出来,提高仿真效率与精度,已成为了当前CAE研究中的研究热点.传统的流程自动化系统的设计无法避免框架化程序设计的弊端,在系统功能扩充以及代码维护及复用上有极大的不足.论文运用面向对象程序设计技术,在一般的有限元软件二次开发技术的基础上,提出了一套基于面向对象技术的流程自动化系统的基本框架,说明了设计思路及意图,并给出实例验证本框架的可行性,展示了本框架的优势.  相似文献   

6.
薄壁梁结构是汽车等运载工具的主要承载构件,提高该类结构的耐撞性对乘员安全具有重要意义。然而,形状优化设计要求多组有限元模型与仿真分析,因此需要特定的建模技术或人工交互。本文提出了一种基于横截面形状的参数化网格变形方法,以实现已有有限元模型的有效重用。以给定有限元模型为输入,采用基于各向异性径向基函数网格变形方法,并结合骨架内嵌空间,可快速生成适用于仿真分析的有限元模型变体。以S形梁轴向冲击耐撞性设计为例,采用所提方法改变构件塑性铰区域的横截面形状,可快速(低于4 s)获取100组局部变形有限元模型,并采用代理模型技术和多目标遗传算法优化结构耐撞性。数值结果显示,构件耐撞性获显著提高,验证了所提参数化变形方法的有效性,展示了与一般形状优化框架的可集成性。  相似文献   

7.
大型直线振动筛动态仿真的研究   总被引:12,自引:0,他引:12  
本文对我国首次设计的27m^2大型直线振动筛进行了动态仿真,探索了大型筛分机械动态仿真理论方法和试验技术,改进了大型筛体的设计,为我国生产大型振动筛探索了可行之路。  相似文献   

8.
隔震结构的研究概况和主要问题   总被引:13,自引:0,他引:13  
杨迪雄  李刚  程耿东 《力学进展》2003,33(3):302-312
简要概括了国内外隔震技术的应用发展状况.系统总结、评述了隔震结构若干方向的研究进展,包括隔震结构的非线性地震反应分析和非线性动力学性态分析、可靠度分析、优化设计、系统识别、试验研究等内容.指出了隔震技术发展中需要解决的几个主要问题,例如新型隔震元件、隔震体系的开发,隔震结构的经济可行性分析,与隔震技术发展相适应的设计、施工规范等.最后在结束语中探讨了隔震设计与基于功能的设计、分灾设计等结构抗震设计思想的关系.  相似文献   

9.
讨论了无线扩频定位系统的关键技术之一——扩频码的设计与实现。首先从实验的角度基于Logistic映射,分析了其所生成的混沌序列的部分相关特性及平衡性,给出了计算机仿真结果;最后从工程角度给出了易于实现的平衡Gold码的设计方法。  相似文献   

10.
为了减少载机交联成本和提高研制效率,基于1553B总线,设计与实现了一个制导炸弹传递对准仿真研究系统.首先分析了1553B总线协议;然后介绍了该仿真系统的结构功能与实现,并对该仿真系统的硬件设计、1553B总线通讯接口设计、传递对准算法设计和主控软件流程设计进行了论述;最后对该仿真系统进行地面跑车试验.试验结果表明,对准完成后惯导的姿态角误差得到了有效的修正,从而证明该仿真系统的设计是成功的.该系统已在某型号项目的研制中得到了成功的应用.  相似文献   

11.
《Fluid Dynamics Research》2006,38(2-3):108-126
The difficulties in computational fluid dynamics (CFD) analysis of outdoor environments are described and new techniques in CFD for overcoming these difficulties are developed. A ‘Software Platform’ is proposed that integrates various numerical analysis tools and that is able to give a complete evaluation of outdoor climates. A number of case studies on designing outdoor climates are reported based on this newly developed Software Platform.  相似文献   

12.
The three fundamental optical phenomena of diffraction, two-beam interference, and transformation by a lens form the basis of modern moiré strain-measurement techniques. The improved understanding of diffraction by superimposed gratings and optical spatial filtering leads to a general gain of freedom in designing moiré experiments. Benefits characteristic of refined but very simple optical-data-processing techniques include simpler apparatus, less-demanding procedure, possible large gains in sensitivity, and the ability to choose certain moiré parameters, such as sensitivity,after an experiment is concluded and the raw data stored. Sample results from a study of strains near cold-worked holes demonstrate that acceptable results can be had with elementary apparatus and systematic exploitation of optical-data processing.  相似文献   

13.
Abstract

In his paper we consider the problem of designing a feedback controller for a thermal fluid. Any practical feedback controller for a fluid flow system must incorporate some type of state estimator. Moreover, regardless of the approach, one must introduce approximations at some point in the analysis. The method presented here uses distributed parameter control theory to guide the design and approximation of practical slate estimators. Wc use finite clement techniques to approximate optimal infinite dimensional controllers based on linear quadratic Gaussian lpar;LQG) and MinMax theory for the Bonssincsq equations. These designs are then compared to full state feedback. We present several numerical experiments and we describe how these techniques can also be applied to sensor placement problems.  相似文献   

14.
The technologies applied by SDO Yuzhnoye to implement the Sea Launch Project are exemplified to describe the recent achievements in designing space launch vehicles. Consideration is given to the loads acting on launch vehicles during long-term sea transportation and prelaunch operations in rough sea. Experimental methods for determining those loads are described, and techniques for reducing them are proposed. Presentation is also given to methods of providing launch safety under conditions of limited space for launch-support equipment and reducing the thermal and vibroacoustic loads on the launcher. The efficiency of the methods described is confirmed by the success of the Sea Launch Project  相似文献   

15.
This paper investigates the problem of fuzzy impulsive control to synchronize two chaotic systems using a novel time-dependent Lyapunov function approach. Compared with the existing time-independent Lyapunov methods, the proposed method enables us to exploit more information on the impulsive intervals. Initially, using the Lyapunov technique and two parameterized linear matrix inequality (LMI) techniques, some less conservative synchronization criteria via a fuzzy impulsive controller using the states of both drive and response chaotic systems are derived. Subsequently, an LMI approach to designing such a fuzzy impulsive controller is developed to realize the synchronization. Finally, the proposed method is applied to the chaotic Lorenz system and Rösler system to illustrate its effectiveness.  相似文献   

16.
数字光弹性法综述   总被引:11,自引:3,他引:8  
将光弹性法与计算机图像处理技术相结合 ,来自动采集光弹性数据和分析应力的方法 ,称为数字光弹性法 ,与传统光弹性法相比 ,它可以进一步提高实验速度和精度。本文详细讨论了以下两个方面 :一是光弹性条纹的细化和倍增处理技术 ;二是自动确定光弹性参数的技术 ,包括相移法、傅立叶变换法、逐步载荷法、广谱分析法和RGB光弹性法等。通过对近二十年来国内外在这些方面的研究、应用和进展作了综述 ,认为采用白光的彩色域相移技术计算光弹性等倾角 ,结合采用白光源或三色光源的相移法来确定光弹性等色线级数 ,有望成为解决静态二维和三维冻结模型薄切片应力分析的最佳方法 ;另外 ,设计一种能实时和同步采集多幅条纹图的实验装置 ,通过相移法来自动获取动态光弹性数据 ,是数字动态光弹性法很有前景的发展方向  相似文献   

17.
Signature analysis has a definite function and role to play in understanding machinery dynamics and maintaining the health of operating systems. It does not, however, provide all the answers. Experimental modal analysis can be used to extend the reach of signature analysis by providing a more fundamental understanding of machinery dynamics. Combined experimental and analytical techniques for system analysis can take a further step in understanding and designing better machinery. These techniques allow the engineer to see how various components or subsystems interact, even before total system hardware is available. They also can provide valuable load information so that better, more efficient component design may be done.
The broad application of system analysis technology is just beginning to take place. Developments in hardware and user-oriented software have taken some of the "black-magic" out of the technology and have made it something that can be used as a routine tool. Many areas are open for development and are actively being pursued. A number of particular interest are:5 coupling of equipment dynamics with dynamic fluid forces created in attached piping; continuation of development of techniques for flexible rotor balancing using a system model, modal data base, and future instrumentation developments;6 additional refinement techniques for coupling of foundation dynamics with equipment dynamics; additional insight in the use of computerized condition monitoring systems by identifying the optimal locations for instrumentation and insight into the proper monitoring system diagnostics.  相似文献   

18.
19.
Basic characteristics of light scattering in an aqueous solution of milling yellow are presented in a form of relations between the scattered radiant power, states of polarization of primary radiation and scattered radiation, observation angle and azimuthal angle.It is found that the state of polarization of the scattered light in milling-yellow solution can be utilized as a foundation of reliable photoelastic scattered-light techniques for flow analysis. However, Rayleight's model of scattering is nnt directly applicable.Paper contains data on major parameters of light scattering, knowledge of which is necessary to correctly design flowbirefringence experiments. In particular, these data can be used to develop a set of conditions and constraints for designing of particular scattered-light flow-birefringence experiments, and of corresponding transfer functions.  相似文献   

20.
变形载体包括光栅、散斑和标记点等,是光学变形测量时的重要载体,关系到测试的成败.基于聚焦离子束(FIB)微加工平台和技术,介绍了微观变形载体的设计、制作方法、程序等要点,并且利用FIB刻蚀微型孔、槽等实现材料表面微观残余应力的测量.分析和讨论了FIB制作变形载体对原有结构的影响和由此引起的残余应力测试误差.结果表明,FIB刻蚀作为一种新型的直写微纳米加工技术,结合高倍显微镜对视场的切换,可以在关键微区准确定位,并制作变形载体和实现变形测量,尤其对残余应力的测量特别有效.  相似文献   

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