中国的载人运载火箭

高可靠、高安全和高质量，确保航天员绝对安全，是对载人运载火箭的最主要要求。简要介绍了CZ-2F载人运载火箭的总体方案、系统组成以及设计的基本原则。     

长征三号系列运载火箭

论述了长征三号系列运载火箭诞生的背景、设计思路、总体技术方案、应用发射结果及其在技术与研制工作方面的特点,展望了其发展前景,指出该系列运载火箭是我国目前性能先进的大型主力商业应用发射火箭群体。     

Metallurgical Analysis of Cracked AA7075 Aluminum Alloy Component Used in Control System of a Satellite Launch Vehicle

Journal of Failure Analysis and Prevention - High-strength aluminum alloy AA7075 forgings are widely used in various control system components of liquid engines of satellite launch vehicles. In one...     

Failure Analysis of a Launch Vehicle Umbilical Shutter Mechanism During Vibration Qualification

Payload fairing (PLF) of a launch vehicle is exposed to harsh vibration environments due to jet noise during liftoff and in-flight aerodynamic noise. Accordingly, the systems mounted on the payload fairing are to be qualified for the vibration levels, predicted corresponding to the envelope of acoustic spectrums at critical instants of atmospheric flight. This paper presents a detailed study of a failure observed on the payload cooling umbilical system, mounted on the cylindrical portion of the PLF structure, during its design qualification vibration testing. The umbilical shutter inadvertently opened during the test. The vibration responses on the shutter, the dynamic behavior of the system, and the forces and moments on the mechanism are analyzed, and the physics of failure is understood. The design marginality is identified, and the shutter locking mechanism reconfigured to achieve the desired level of robustness in the system.     

车辆制动检测实验台架的研制开发

利用转鼓实验台,自行设计了的车辆制动检测实验系统,包括机械加工部分以及数据采集和处理系统,可以对车辆制动时的主要参数进行测量,并由此计算出其它参数.同时结合开发的防抱死制动系统,在此检测台架上进行了相关实验,达到了理想的效果,为制动实验提供了一套实用的方法.     

Failure Analysis of AISI 440C Steel Ball Screws Used in the Actuator System of a Satellite Launch Vehicle

In view of its excellent wear and corrosion resistance, AISI 440C steel is the material of choice for the fabrication of ball screws used in actuator systems of satellite launch vehicles. During the routine acceptance test of a ball screw, longitudinal cracks were observed at the shaft location of the ball screw. The optical microstructure of the ball screw material (AISI 440C) revealed the presence of aligned carbides (carbide banding). Fractographic observations revealed the cracking to be along the carbide bands. Based on detailed optical and scanning electron microscopic observations, the cracking of the ball screws was attributed to the carbide bands.     

热力设备停用缓蚀剂的研究

通过高压釜试验和电化学极化曲线测试并结合硫酸点滴和水滴评价试验，评价了新型热力设备停用保护缓蚀剂（TW）对热力设备的几种主要钢材的缓蚀效果，用XPS表面分析方法探讨了TW的缓蚀机理。结果表明：TW通过同金属表面的Fe原子发生化学配位形成一层致密的保护膜，是一种性能良好的热力设备停用保护缓蚀剂。     

Failure Analysis of AISI 304 Stainless Steel Sleeve Used in High-Pressure Hose Assembly of Actuation System of a Satellite Launch Vehicle

Hydraulic control actuation systems in launch vehicles use flexible hoses for transmission of forces to actuators at different locations. The hose ends are connected to the interface adapters by AISI 304 stainless steel sleeves. These sleeves are assembled to nipple end fittings of the high-pressure hose by a swaging operation to obtain leak-proof hose assemblies. The swaging operation is carried out at room temperature by a hydraulically operated swaging machine. Performance of the system as a whole requires strict adherence to the quality standards maintaining the critical interface dimensions within specified tolerances and ensuring the compression given to the swaged joint through the sleeve. If the joining forces are less, this can result in loose joints and gross leakage, whereas excessive compression can cause damage to the parts of the system namely the sleeve, stainless steel braid, PTFE or the adapter. The swaged joint is a single-point failure mode, indicating that a failure in the joint can lead to mission failure. It has to withstand harsh environments such as high pressure, low and high temperature extremes, fatigue loading due to pressure cycling as well as vibration. Therefore, as part of design verification, a detailed qualification plan has been prepared and the hoses were tested as per the plan. As per the test plan, these hoses undergo acceptance tests which include pneumatic and hydraulic pressure testing. During acceptance testing of hoses, one of the hose sleeves was found to be cracked. The cracking was observed after carrying out the pneumatic test when the assembly was being prepared for hydraulic pressure set-up. This paper describes the detailed metallurgical investigation carried out to understand the cause of failure and actions taken to avoid similar failures.     

柔性热防护系统的发展与应用

热防护系统是发展航天器必须解决的关键技术,而柔性隔热材料由于具有可重复使用、质量轻、维修时间短等优点被广泛采用。介绍了当前各种热防护系统结构与材料的发展状况,并具体叙述了飞行器减速伞的结构、展开、热流分布以及所用柔性材料,对我国柔性防热材料的发展提出了建议。     

特种车发动机热负荷试验研究

本文以我国某特种车试验数据为基础,对该车发动机在高原地区和湿热地区的热负荷进行了分析,并针对高原、湿热两个地区的特殊环境特点,对试验数据进行了对比分析;采用国外广泛采用的ATB特性评价方法,对发动机在湿热地区的冷却性能进行了评价.     

非烧蚀防隔热材料表面热防护涂层的研究进展

防隔热材料在高速飞行器中扮演着重要的角色,而其表面热防护涂层更是决定高速飞行器能否成功运行的关键。从制备、机理和性能等方面回顾了不同类别非烧蚀防隔热材料表面热防护涂层的研究进展和应用现状,总结了传统热防护涂层存在的问题,并对未来航天领域的热防护涂层的研究进行了展望。     

基于VXI总线的无人机综合测试系统的设计

利用VXI总线技术开放式的体系结构和模块化的自动测试技术的优势,结合国产无人机现状,研发了基于虚拟仪器的综合检测系统.该系统具有通用性好、扩展性强、标准化程度高的特点.文章给出了测试仪的硬件配置和在LabWindows/CVI环境下的软件模块化设计方案及实现方法.     

锅炉热效率监测及分析

本文通过对典型用能设备—锅炉的排烟温度、过量空气系数、炉渣含碳量和炉体外表面温度四项指标进行节能监测,分析影响锅炉热效率的因素,为今后更好的开展节能和监测工作提供借鉴。     

乘用车车轮销轴声学灵敏度仿真与实验分析

为分析路面激励引起的车内结构噪声,建立整车结构有限元模型及流体声腔有限元模型;在车轮销轴处施加激励,仿真计算车内对销轴处的声学灵敏度。对仿真结果进行功率叠加,得到车内对销轴处的整体声学灵敏度。该整体声学灵敏度可作为分析路面激励引起的车内结构噪声的依据。在同等边界条件下,对有限元计算结果进行试实验验证。通过模态贡献量分析等方法分析车身结构、后悬架等对车轮销轴声学灵敏度的贡献;对0~200 Hz车内结构噪声处理提出相应的建议。     

某三轴越野运输车共振试验分析和改进

在公路行驶过程中,发现某三轴越野运输车车速在50 km/h~60 km/h范围内存在较强烈的共振现象,驾乘人员主观感受舒适性较差。通过理论分析与道路行驶试验相结合的方法,找出该车型在此车速段整车共振频率为3.7Hz左右,因车轮产生的摇振频率与整车的固有频率相接近而产生共振。为消除振动现象,本着对车辆改动最小的原则,通过调整前后悬架板簧刚度方法调整整车的振动频率。试验结果表明,振动噪声降低明显,驾乘人员乘坐舒适性和整车平顺性得到改善。     

垂直热发射过程弹架耦合作用研究

研究裸弹垂直热发射过程系统的动态响应及其对导弹运动的影响。对车载导弹发射系统进行了简化和等效建模,进行了导弹起飞过程的理论分析,基于动力学和有限元软件建立了系统刚柔耦合多体动力学模型,对发射过程展开了动力学仿真与分析,并进行了多刚体与刚柔耦合两类模型计算结果对比。数值模拟结果表明,导弹起飞过程与发射车的耦合作用明显,系统振动对导弹起飞姿态产生影响,发射车振动衰减特性良好,柔性发射台模型能够较好反映发射过程系统动态响应以及弹架耦合特性。     

汽车室内道路模拟试验系统控制算法的研究

为了有效的进行汽车道路模拟试验，首先要通过系统识别获得整个试验系统的频响函数矩阵[FRF]，之后在目标信号模拟过程中获得满足试验要求的驱动信号。详细叙述了在系统识别过程中，对识别所得模型进行评判的相干函数法及预测法，和为获取更加准确模型而使用的模型平均法；以及为消除整个实验系统的非线性因素而在目标信号模拟过程中采用的迭代算法。最后，通过具体的试验对上述的控制算法进行了验证。     

车辆右转弯提示音试验方法分析及验证

《车辆右转弯提示音要求及试验方法》标准(报批稿)规定了右转弯提示音装置及配备该装置的整车需要满足的提示音条件。通过分析该报批稿的相关要求,对整车右转弯提示音频率、声压级的数值要求进行了试验论证,对比了整车提示音和零部件级别即提示音装置本身的声压级,通过试验证明了该数值的合理性,并对后续标准实施和试验提出了合理化建议。