Integrated Avionics: Watershed in Systems Development

For aeronautical weapon systems now entering development, avionics will equal or surpass airframe, propulsion, and weapons in establishing system effectiveness, both in terms of mission accomplishment and in terms of reliability, availability, supportability, and life cycle cost. Emerging technologies created the opportunity to satisfy demanding operational needs and to provide the means to upgrade systems against an evolving threat. This requires, however, basic changes in the skills, design methods, and constraints applied to avionics development. This paper highlights trends in avionics technology and systems and suggests some of the new ground rules which must be imposed to realize their full potential. Avionics considerations must be a central element of system development from the very outset, and the process of conceptual planning and program estimation must take the new realities of avionics into account.     

Switched Ethernet testing for avionics applications

Switched Ethernet is being implemented as an avionics communication architecture. A commercial standard (ARINC-664) and an aircraft vendor-specific implementation known as avionics full duplex switched Ethernet (AFDX) have been developed that defines the topology and use of switched Ethernet in an avionics application. In avionics applications, the movement of data between devices must take place in a deterministic fashion and must be delivered reliably. All aircraft flight hardware must be tested to be sure that it will communicate information properly in the switched Ethernet network. The airframe manufacture must test the integrated network to verify that all flight hardware is communicating properly. Testing and maintenance testing is required to perform data communication level testing of switched Ethernet architectures for avionics applications to insure that all communication is deterministic and reliable. This paper provides an overview of a switched Ethernet avionics network and identifies the testing challenges associated with a switched Ethernet avionics application. A practical implementation performing the required tests is discussed.     

高超声速飞行器机体/推进一体化设计的启示

机体/推进一体化设计是吸气式高超声速飞行器的关键技术。飞行器的前体和后体既是主要的气动型面,又是发动机进气道的外压缩型面和尾喷管的膨胀型面,一体化设计直接影响飞行器的气动与发动机性能。本文阐述了吸气式高超声速飞行器的主要特点,梳理了飞行器的推阻匹配、升阻比特性、操稳匹配等主要气动设计问题。通过对国外典型高超声速飞行器机体/推进一体化设计技术的综合分析,总结了前体/进气道、后体/尾喷管、边界层强制转捩装置等关键部件的气动设计方法,获得了有意义的启示,可为后续吸气式高超声速技术研究提供重要参考。     

航空数字数据传输系统接口设计

随着机载电子设备向标准化、综合化发展 ,航空数字数据传输系统的设计越来越受关注 ,目前广泛采用ARINC42 9总线作为航空电子系统间信息传输的标准。文章介绍了两种总线接口芯片EF44 42、HS - 32 82 ,以及实现ARINC42 9通信的接口电路     

Avionics for Aeronautical Systems

Advancements in technology have led to increased demand for avionics in airborne applications. Although aeronautical system suppliers have implemented improved procedures and design approaches which are generally effective, challenges continue to exist. This paper explores several areas where overall aeronautical system design might be improved by proper emphasis on avionic subsystem design. The topics selected include standardization, weight impact, environmental control, maintainability, and avionic equipment growth. Comparisons are made in terms of ultimate cost to the aeronautical system user.     

Multidisciplinary Design and Optimization of Multistage Ground-launched Boost Phase Interceptor Using Hybrid Search Algorithm

This article proposes a multidisciplinary design and optimization (MDO) strategy for the conceptual design of a multistage ground-based interceptor (GBI) using hybrid optimization algorithm, which associates genetic algorithm (GA) as a global optimizer with sequential quadratic programming (SQP) as a local optimizer. The interceptor is comprised of a three-stage solid propulsion system for an exoatmospheric boost phase intercept (BPI). The interceptor's duty is to deliver a kinetic kill vehicle (KKV) to the optimal position in space to accomplish the mission of intercept. The modules for propulsion, aerodynamics, mass properties and flight dynamics are integrated to produce a high fidelity model of the entire vehicle. The propulsion module comprises of solid rocket motor (SRM) grain design, nozzle geometry design and performance prediction analysis. Internal ballistics and performance prediction parameters are calculated by using lumped parameter method. The design objective is to minimize the gross lift off mass (GLOM) of the interceptor under the mission constraints and performance objectives. The proposed design and optimization methodology provide designers with an efficient and powerful approach in computation during designing interceptor systems.     

分布式动力系统尾缘射流与边界层抽吸的数值分析

为研究带有边界层抽吸的分布式动力系统尾缘射流对机身气动性能及推进效率的影响,将机身简化为二维翼型,并加入尾缘射流及边界层抽吸的作用,利用数值模拟的手段来研究来流攻角、射流偏转角、边界层抽吸对推进效率及气动性能的影响,为分布式动力系统的设计与应用提供初步的建议.结果表明在中、小来流攻角(2°及0.6°)的情况下尾缘射流及边界层抽吸能够提高升阻比,推进效率可超过80%;而在大来流攻角(4°)情况下射流偏转角增大使翼型的阻力大幅上升,对气动性能和推进效率产生极为不利的影响.      

一种基于模型和原型系统仿真的综合模块化航空电子系统开发方法

针对综合模块化航空电子系统的复杂性和传统瀑布式开发方法存在的问题与挑战,在Ⅴ型开发模型的基础上提出了一种基于模型和原型仿真的综合模块化航空电子系统的开发方法.该方法通过在需求捕获、方案设计和工程开发阶段分别构建相应的原型系统进行仿真与验证,实现对系统需求进行早期需求确认与设计验证(V&V)、原型仿真与集成.采用该方法的好处是通过原型仿真,系统设计师可以在开发早期向用户展示他们的设计成果,以满足用户的需求;可以帮助系统开发人员以低成本实现连续的虚拟集成和迭代确认与验证,从而缩短系统研制周期,降低系统开发成本.飞行管理系统开发应用案例表明了该方法有效性.     

飞机综合航电系统总体设计综合评估方法

 航空电子系统的费用 效能是飞机总体系统效能的重要组成部分，也是降低飞机寿命周期费用的关键之一。在航空电子系统的总体设计阶段，传统的系统评估和优化方法主要针对的是独立子系统/设备的费用或效能指标。综合航电系统设计方案的费用 效能重要指标包括：可支付性、构型能力、任务能力、可靠性、维修性、测试性和技术风险，以组合的方式获得了相应的综合评估准则，给出了计算公式。以某新研航电系统作为实例演示了综合评估方法的实施情况，演示的重点集中于总体设计方案的可视化量化评估分析。该综合评估方法已显示出其在实际工程设计中的可行性和应用价值。     

论机动飞机机体/进气道一体化

机动飞机／发动机一体化,一直是多年来国际上研制高机动性战斗机中不容忽视的一项重大课题,目的在于提高发动机包括进气道、尾喷管在内的推进系统的工作效率和稳定性。列举了国外的一些型号,特别是有分叉进气道战斗机在研制中必须加以考虑的一体化问题,并从设计原理的角度,给出了一些旨在提高性能与安全性的可供选择的进气道构形。     

高超声速飞行器推进模块的设计参数分析

通过斜激波理论、准一维工程估算和特征线方法建立了一个与飞行器机体一体化的推进系统模块的气动分析模型,其中采用参考温度法估算模块的粘性效应。在此基础上分别研究了飞行器前体长度、前缘角及推进模块宽度等关键设计参数对推进模块气动性能的影响。结果表明:增大模块前体长度将使模块的升力、净推力和比冲先增后降;增加前缘角将增加升力,但降低净推力;增加模块宽度会导致等效升力下降。因此,在设计此类高超声速巡航飞行器时,应采用模块化的推进系统并折衷选择前体长度和前缘角的大小。      

尾喷流对飞机升力特性影响的研究与估算

本文对飞机低速飞行时尾部喷流对飞机机身的影响进行了定性讨论和研究，阐明了发动机尾喷流对飞机水平尾冀的影响。在大量实验数据基础上给出了供飞机设计者在飞机初步设计阶段使用的升力特性工程估算公式和曲线。     

飞机概念设计阶段的控制权限评估

所有的飞机都必须满足可控性要求。军用飞机还有额外的机动性要求，飞机满足这些要求的能力受到其控制权限的限制。因此，在概念设计阶段的早期对候选方案的控制权限进行评估是必须的。本文给出一组简单的方法，使得设计者在对概念进行深化研究和开展详细的控制系统设计之前能够对其控制权限进行近似的评估。     

大展弦比飞机翼身结构不同刚度对结构响应的影响

为了研究大展弦比双机身布局无人机翼身结构不同刚度对结构响应的影响,本文采用有限元分析与满应力优化相结合来探讨这一问题。计算结果表明:机翼与机身之间不同刚度对结构响应存在影响。建议结构设计时注意这一现象并加以利用,从而得到轻量化的结构设计。针对算例进一步计算与分析表明:采用本文方法得到的结构优化方案,同样也能够满足该飞机的静、动气弹要求。结论:采用本文方法,不仅可以研究飞机部件之间不同刚度对飞机结构响应的影响,还可以进行全机的结构方案设计,并对此方案进行刚度、强度、颤振和控制面效率的分析与评估。     

高超声速飞行器控制一体化设计

针对高超声速飞行器模型具有气动/推进/控制强耦合和强非线性的特点,提出了一套面向控制的一体化设计方案.在概念设计阶段,以飞行器控制性能为优化目标,对气动、推进、结构、控制等参数进行一体化综合优选来设计飞行器.考虑模型生成的保真度要求和计算效率,建立高超声速飞行器参数化的数学模型,并设计LQR(linear quadratic regulator)跟踪控制器.通过不断调整飞行器构型,比较控制相关的动静态特性和控制效果,面向控制需求选择新的飞行器构型,并进行了仿真验证.仿真结果表明:控制一体化设计方法应用于高超声速飞行器概念设计初期可以扩大飞行包线,有效增大失速裕度,减小油耗,提高操纵面效能,降低发动机壅塞制约,对高超声速飞行器的设计效率和控制性能的提高起到了指导性的作用.      

电子对抗仿真器的设计

用电子对抗系统仿真器代替真实的设备参与飞机航电系统综合试验, 是为了获得更好的动态效果, 减少测试的复杂性, 降低实际费用。本文在分析电子对抗系统功能的基础上, 提出了仿真器的基本设计方案及软件设计技术, 最后, 介绍了软件测试方法。     

翼身融合民机总体气动技术研究进展与展望

翼身融合（BWB）布局作为下一代亚声速民机主流方案已得到共识，研究步伐正在加快，进入工程应用指日可待。在回顾国内外BWB民机发展历程的基础上，简要阐述了飞翼布局（FW）和BWB布局的差异，明确了BWB概念特征及应用范围。聚焦BWB飞机总体气动设计中的技术挑战和对策，重点论述分析了BWB布局技术瓶颈及设计思想演化，新型结构与重量估算、适航符合性等总体设计问题，气动布局设计原则、高-低速性能协调等气动布局设计问题，飞-发干扰与一体化设计、新型发动机技术应用等飞机-发动机综合集成设计问题，降噪技术及其衍生的设计冲突、考虑噪声指标的总体设计策略等问题。并从技术进展和工程可实现性角度，展望了BWB民机的发展趋势。     

基于知识的可扩展飞机概念设计环境原型研究(英文)

由于飞机概念设计阶段所涉及任务的高度复杂性和多学科集成性,知识和经验成为设计师开展设计任务的基础。即使针对同一个设计任务,不同的设计师仍需要适合他们自己的设计知识、方法和工具来满足其个体要求。针对以上需求本文提出了一种基于知识的可扩展的构建飞机概念设计系统的方法。基于这种方法建立了具有开放式框架基于知识的飞机概念设计环境KEACDE。设计师应用此环境可以封装集成所需的设计分析组件并构建针对不同需求的飞机概念设计系统。定义了KEACDE的系统框架,知识组件封装方法和可扩展基础数据库建立方法。应用KEACDE实现了一个民用飞机概念设计系统的构建。最后给出了民用飞机设计实例以说明系统的可行性。     

Aerodynamic configuration integration design of hypersonic cruise aircraft with inward-turning inlets

In this work,a novel airframe/propulsion integration design method of the wing-body configuration for hypersonic cruise aircraft is proposed,where the configuration is integrated with inward-turning inlets.With the help of this method,the major design concern of balancing the aerodynamic performance against the requirements for efficient propulsion can be well addressed.A novel geometric parametrically modelling method based on a combination of patched class and shape transition (CST) and COONs surface is proposed to represent the configuration,especially a complex configuration with an irregular inlet lip shape.The modelling method enlarges the design space of components on the premise of guaranteeing the configuration integrity via special constraints imposed on the interface across adjacent surfaces.A basic flow inside a cone shaped by a dual-inflection-point generatrix is optimized to generate the inward-turning inlet with improvements of both compression efficiency and flow uniformity.The performance improvement mechanism of this basic flow is the compression velocity variation induced by the variation of the generatrix slope along the flow path.At the design point,numerical simulation results show that the lift-to-drag ratio of the configuration is as high as 5.2 and the inlet works well with a high level of compression efficiency and flow uniformity.The design result also has a good performance on off-design conditions.The achievement of all the design targets turns out that the integration design method proposed in this paper is efficient and practical.     

A Digital Map Set for the Night Attack Aircraft

There has been much interest recently in applying cartographic digital data bases to advanced avionics systems as a solution to specific problems associated with night attack aircraft missions. The tremendous computer horsepower required to accomplish this task in real-time in an airborne environment is well documented. Hardware implementation of complex algorithms traditionally has produced custom devices which accomplish a specific function on a specific data structure. Historically, this has resulted in powerful but inflexible systems incapable of adapting to the changing requirements of military missions. In an age of evolving technology, these pitfalls must be avoided by incorporating expected changes into the design of digital map systems. If they are made to accommodate a variety of cartographic data bases and allow for programmable manipulation of those bases, this new class of digital map sets can be reconfigured at the software level to meet the changing requirements of aircraft missions. This paper addresses current design concepts for such a map system on a Night Attack aircraft. The focus is on issues concerning the development and handling of existing map data products to meet current system requirements. This system, called the Digital Map Set (DMS), is being designed to accomplish the classical manipulations of Defense Mapping Agency Digital Land Mass System data. Additionally, aeronautical charts, aerial reconnaissance photos, flight plan data, and other two-dimensional bit mapped graphics also are accommodated. Mission requirements relating to the cartographic data bases shall be discussed along with ground support station and airborne system design issues.