Walter Thiel—Short life of a rocket scientist

In 2012 we celebrate the 70th anniversary of the first successful rocket launch that reached a height of 84.5 km and had a speed of 4.824 km/h (5x sonic speed). This rocket flew 190 km to the target location. One of the masterminds of this launch was Walter Thiel, a German chemist and rocket engineer. Thiel was highly talented, during his education from primary school until diploma exams he always received a grade of A in his exams. He was called “the student with the 7 A grades”. In 1934 Thiel became Dr.-Ing. (chem.), with the highest possible honor (summa cum laude), when he was only 24 years old. He started to work for the rocket development department at Humboldt University, Berlin. Walter Dornberger asked him to leave the university research department and become head of rocket propulsion development in his team in Kummersdorf, near Berlin. Thiel's groundbreaking ideas for the rocket engine would lead to a significant reduction in material, weight and work processes, as well as a shortening in the length of the engine itself. Thiel and his team also defined the fuel itself and the best ratio of mixture between ethanol and liquid oxygen for the engine. In 1940 the propulsion team moved from Kummersdorf to Peenemünde after the launch sites were completed there. Thiel became deputy of Wernher von Braun at the R&D units. One of Thiel's team members was Konrad Dannenberg, who later became famous in the development of the Saturn program. On the night from August 17 to August 18, 1943, Thiel and his family (wife and two children) were killed during a Royal Air Force bombing raid (Operation Hydra). The Moon crater “Thiel” on the far side of the Moon is named after Walter Thiel. The research results of Walter Thiel had a strong impact on the United States' rocket program as well as the Russian rocket development program.     

叉流式热交换器动态特性的数值计算

建立了叉流式热交换器在热流体和冷流体都随时间变化的条件下的动态二维数学模型。使用一阶精度显式格式建立了热交换器的有限差分模型。该模型能够满足任意变化的温度及流量入口条件。经过实例计算表明,所得的理论热交换器出口平均温度变化曲线与相应的空中试飞测试曲线有较好的跟随性、吻合程度良好。     

选择工程材料的一种定量化方法

本文简述了选择工程材料时应考虑的部分因素,论述了材料在某些载荷作用下其机械性能与成本之间的关系,从而给出了可以定量化比较和计算的选择工程材料的方法。     

温度计量技术在航空发动机试车台健康管理中的应用

分析了航空发动机试车台温度配置参数传统离线校准方法,针对其存在的反复拆装耗时长且易引发故障、缺少系统综合误差的判定方法等不足,开展发动机试车台静态状态下的整机在线校准方法研究。通过给被校准参数传感器提供标准热源的方式,开展温度传感器及温度通道（温度仪表）在线整机校准。通过对发动机试车台系统模拟仪表显示结果与标准器读数进行比较,确认在线校准的有效性,实现了试车台系统综合误差校准,为试车台健康管理提供支撑。     

老龄波音757飞机结构损伤特性分析

通过对老龄波音757飞机结构损伤特性的分析和隐蔽性等特点,建议实施有针对性、及时性、扩展性、构的安全。得出其具有集中性、蔓延性、严重性、重复性彻底性和双重性的维修,以确保老龄757飞机结     

基于ADN基液体推进剂的无毒可贮存空间发动机试验研究

对一台基于ADN基液体推进剂的无毒空间发动机进行了试验研究。通过三维PDA(Phase Doppler Anemometry)综合测量系统,获得了发动机喷注器的雾化性能,得到了喷注器雾化液滴空间上的双分支分布以及液滴尺寸上的双峰状分布;通过高空模拟热试车试验,对于发动机的稳态、脉冲工作性能、工作过程中包含的催化分解及燃烧反应特性有了深入理解,研究了发动机启动时燃烧室内的建压和温度抬升过程,揭示了ADN基发动机在点火过程中体现出的点火延迟特性。     

基于QPSO算法的压气机特性代理模型优化

考虑到小样本特性数据情况下进行部件特性数据的二维线性插值精度低,提出一种基于量子粒子群优化(QPSO)算法的压气机特性代理模型优化方法。针对原始Kriging模型对其相关模型参数的初始值极度敏感以及易限于局部最优解的缺陷,利用QPSO算法对Kriging的相关模型参数进行全局寻优,克服了基于梯度的模式搜索法对于参数初始值的依赖,经测试该方法具有较好的效率以及稳定性。将该优化模型扩展应用于低压压气机特性代理模型建立与重构。经验证,在小样本特性数据下,基于QPSO的压气机特性Kriging模型仍具有较高精度,应用前景可观。     

Blade containment evaluation of civil aircraft engines

The potential hazard resulting from uncontained turbine engine rotor blade failure has always been the long-term concern of each aero engine manufacturer, and to fully contain the failed blades under critical operating conditions is also one of the most important considerations to meet the rotor integrity requirements. Usually, there are many factors involving the engine containment capability which need to be reviewed during the engine design phases, such as case thickness, rotor support structure, blade weight and shape, etc. However, the premier method to demonstrate the engine containment capability is the fan blade-off test and margin of safety (MS) analysis. Based on a concrete engine model, this paper aims to explain the key points of aero engine containment requirements in FAR Part 33, and introduces the implementation of MS analysis and fan blade-off test in the engine airworthiness certification. Through the introduction, it would be greatly helpful to the industrial community to evaluate the engine containment capability and prepare the final test demonstration in engine certification procedure.     

基于球堆叠的月壤蓄热器传热特性数值研究

月壤蓄热是月球原位资源利用的一种重要方式，也是解决未来月球基地能源需求的最具潜力的途径之一。针对月壤蓄热过程，建立了基于球形堆叠的月壤蓄热器多孔介质蓄热模型。蓄热器的壳体采用登月舱下降级的燃料罐，流体传热介质采用氦气。通过数值模拟的方法研究了不同流动压降下月壤蓄热球堆叠方式、球直径对蓄热器传热过程的影响规律和机理，并分析了蓄热动态过程。研究结果表明，月壤蓄热球在简单立方体均匀堆叠（SC）和面中心立方体均匀堆叠(FCC)两种方式下，SC堆叠方式的综合蓄热指数比FCC模式可提高302%；同时还发现月壤蓄热球的直径存在最优值，可使得蓄热器在单位泵功下获得最大的蓄热量，并且该最佳值随着流体进出口压差增加而减小。该研究可为未来月壤蓄热器的设计和优化提供理论指导。     

专用测试装备计量特性的分析方法

为解决专用测试装备计量特性的分析评定难题，提高装备量值溯源的有效性，从装备使用者视角出发，以测试能力为基点，应用系统分析法，形成了包括方法思路、识别范围、“可计量”原则、分析步骤和结果表达等内容的计量特性分析方法。最后，以炮口冲击波测试系统为例，对该分析方法的应用进行了验证。结果表明：该方法简单易行，既可以为在役装备重新评定计量特性提供支持，也可以为新建（或在研）装备论证提供参考。