基于MBSE的副翼及其操纵系统研发技术及应用

飞机的设计研发是一项涉及多学科领域、多目标、多约束的复杂系统工程过程,系统耦合紧密、参与人员众多、设计信息庞杂,以文档为中心的需求管理等传统研发方法突显出一定的困难,亟需探索新的飞机设计研发方法。以副翼及其操纵系统为研究对象,对基于模型的系统工程(Model Based System Engineering,以下简称MBSE)方法进行了探索研究:采用达索MBSE方法论-MMS(Modeling Methodology for Systems,以下简称MMS),从使命、服务、功能和组件不同视角对副翼及其操纵系统研发的各个方面进行解析,进而完整定义系统;利用达索3D Experience平台,通过RFLP系统工程架构,进行了副翼及其操纵系统的需求开发、功能分析及逻辑架构设计,完成了需求、功能、逻辑架构、系统仿真、物理设计等模型的关联追溯,实现了以达索MBSE方法论为核心的研发技术的有效应用。     

面向航空装备维修过程的MRO系统开发及应用

以降低航空装备故障率,保证维修进度,提高维修效率和降低维修成本为目标,在深入研究航空装备维修管理关键技术及业务过程的基础上,提出基于维修BOM的航空装备全生命周期状态管理机制。应用精益生产、精确保障的管理理念,建立面向航空装备维修过程的MRO系统,管理航空装备产品维修从返修入库到发货出库的闭环过程,为航空装备综合保障档案的建立提供有力的数据支撑。     

通用航空产业发展途径探讨

通用航空由于应用范围广且对经济有较强的拉动作用,受到了各级政府部门的重视,国家的＂十二五＂规划已经将其列为国家的战略新兴产业。针对我国通用航空发展极度落后的现状,分析了制约通用航空产业发展的主要因素,包括空域管制、通用航空法律法规不健全、专业人才短缺以及航空保障设施落后等,探讨了通用航空产业的发展途径,提出了加强宣传、政府主导、专业人才培养等一些有价值的建议。     

Sensitivity analyses of satellite propulsion components with their thermal modelling

Performing the sensitivity analyses of the contact conduction and the position of thermostat on the basis of the thermal model established, the study of thermal design is accomplished for the preparation of possible mechanical interface change of the satellite propulsion system depending on the satellite system design. A relatively simple thermal model is taken into consideration for the convenience of the analysis. A variety of the spacecraft bus voltages and the contact resistances are examined as well as the position of thermostat on propulsion components. As a consequence, even though the mechanical interface condition is changed on the same module, the successful thermal design could be achieved if we design the heater to have sufficiently large power with reference to the heritage value of contact resistance. Besides the reasonable performance on the thermal control is assured with the thermostat location errors, if the uncertainty in the position of thermostat is not quite large when assembling tank module.     

基于双谱特征的个体辐射源识别

针对个体辐射源识别困难的问题,提出了一种基于双谱分析的个体辐射源识别新方法.首先用双谱分析法提取信号的双谱对角切片,利用主成分分析法(PCA)从大量训练样本特征中挑选低维、低复杂度的特征矢量,并融合对分类具有显著贡献的辐射源属性参数作为识别特征矢量.最后采用势函数分类法实现雷达辐射源识别.仿真结果表明基于双谱的识别法能...     

略论发动机涡轮叶片的振动疲劳

针对发动机涡轮叶片的振动及振动疲劳破坏进行了理论分析。通过理论分析和实验，说明了叶片对抗振对疲劳的能力主要取决于性质及叶片的形式、表面状态，而与静强度无关。并对改进设计和工艺，充分挖掘材料潜力，加强对叶片防护，提出了建议和设想。     

某涡扇发动机加速过程仿真研究

对航空发动机控制系统进行仿真是航空发动机可靠性工程的研究方向之一.本研究针对发动机在加速过程中必须保证发动机不会发生喘振、不出现超温的情况,对加速过程进行了分析.采用部件法建立了分开排气的涡轮风扇发动机加速过程的稳态模型和动态模型.利用Matlab语言及其函数库编写了基于Newton-Raphson的稳态算法,并进行了稳态仿真,得出了高压转速、低压转速、推力等性能参数与供油量之间的关系.研究了迭代法,利用Matlab (Simulink)实现了涡扇发动机的动态仿真,给出了不同加速供油情况下的性能变化情况.最后对3种不同加速时间下的喘振裕度进行了分析,得出了不同加速时间对喘振的影响.     

飞机全三维快速响应试制应用技术

提出了在飞机研制中采用全三维快速响应试制技术,以全三维数字化设计数模为核心,三维设计、三维制造、三维检验的技术体系。这种技术体系设计/工艺高度并行,单一数据源时时共享,并作为唯一依据贯穿飞机研制全生命周期,"边设计、边制造",制造技术前移。在新型研发平台上建立了以设计与制造一体化为核心的快速试制技术体系,在新技术应用上上了一个台阶,重量控制精准、试制流程简捷、技术体系先进、技术手段实用,实现了"好、快、廉"的设计目标。     

美国通用航空产业发展的经验剖析及启示

美国是世界通用航空产业最为发达的国家,其发展得益于政府实施的产业政策和保障措施。与美国相比,我国通用航空产业发展仍处于起步阶段。伴随着中国经济结构转型升级,我国通用航空产业将迎来良好发展机遇。因此,应该借鉴美国发展通用航空产业的经验,在顶层设计上统筹规划,构筑和完善符合中国实际的法律与政策体系,出台相关具体措施,以推动我国通用航空产业健康较快发展。     

A novel target detection approach based on adaptive radar waveform design

To resolve problems of complicated clutter, fast-varying scenes, and low signal-clutterratio (SCR) in application of target detection on sea for space-based radar (SBR), a target detection approach based on adaptive waveform design is proposed in this paper. Firstly, complicated sea clutter is modeled as compound Gaussian process, and a target is modeled as some scatterers with Gaussian reflectivity. Secondly, every dwell duration of radar is divided into several sub-dwells. Regular linear frequency modulated pulses are transmitted at Sub-dwell 1, and the received signal at this sub-dwell is used to estimate clutter covariance matrices and pre-detection. Estimated matrices are updated at every following sub-dwell by multiple particle filtering to cope with fast-varying clutter scenes of SBR. Furthermore, waveform of every following sub-dwell is designed adaptively according to mean square optimization technique. Finally, principal component analysis and generalized likelihood ratio test is used for mitigation of colored interference and property of constant false alarm rate, respectively. Simulation results show that, considering configuration of SBR and condition of complicated clutter, 9 dB is reduced for SCR which reliable detection requires by this target detection approach. Therefore, the work in this paper can markedly improve radar detection performance for weak targets.