热致变色涂层技术研究进展

热致变色涂层技术是航天器热控分系统的一项重要技术,对于未来航天器执行多任务、适应空间复杂多变的热环境具有重要意义。文中分析了航天器热控对热致变色涂层技术的需求,介绍了热致变色涂层的技术原理和国内外研究情况。在此基础上,总结了热致变色涂层技术的发展规律及趋势,并对我国热致变色涂层技术的后续发展提出了建议。     

导电高分子电致变色智能热控器件

采用简单的旋涂、喷涂等方法,制备了一种由可溶性聚苯胺为主体电致变色智能热控器件.该器件的基底为聚酯,固体电解质为锂盐/聚丙烯腈.通过电切换调控,该器件发射率能够在0.46-0.75内调控,且红外光谱反射率变化大于38%.研究了厚度、预掺杂酸种类、浓度等对聚苯胺活性层发射特性的影响;考察了导电高分子聚苯胺层厚度、电切换电压等因素对涂层体系发射率调控的影响.结果表明发射率的调控范围与电化学还原的深度密切相关,通过调节材料厚度、掺杂酸种类等可有效提高发射率调控范围.该导电高分子电致变色智能热控涂层在航天器热控制方面展示了良好的应用前景.     

美国用于空间站辐射器中的热控涂层

综述了六种美国可用于空间站辐射器中的热控涂层。从涂层的性能、价格、质量以及成熟性研究，对这六种热控涂层进行了评价。结果表明，Z－93型热控涂层最适合用于空间站的辐射器中，镀银F－46薄膜型热控涂层次之。     

卫星热控涂层地面模拟试验与在轨验证比对分析

卫星在轨运行期间,热控涂层要经受空间复杂环境效应的影响,其光学和热控性能逐渐下降,影响卫星可靠性和寿命。本文利用卫星搭载技术,完成热控涂层5年的在轨试验,验证空间多因素环境对热控涂层的影响。同时,利用地面模拟试验装置,模拟空间质子、电子、紫外等5年的辐照剂量对热控涂层的作用。对在轨试验结果进行解读和分析,并与地面模拟试验结果进行比对。结果显示,在搭载试验和地面试验前,热控涂层太阳吸收比（α_s）为0.12,经5年在轨搭载试验后,α_s退化为0.23。经地面模拟试验后,α_s退化为0.22。搭载试验和地面试验的热控涂层性能均呈现线性退化规律,表明在确定的轨道环境和固定的剂量率条件下,热控涂层的退化与环境作用时间正相关,同时验证了地面试验的有效性。     

俄罗斯空间有机热控涂层发展的现状及动向

评述了俄罗斯卫星及空间站常用的两类空间有机热控涂层－高反射率白色涂层和高太阳吸收率黑色涂层的技术水平,并对其发展的新动向作了分析,为我国发展新一代长寿命卫星和空间站计划所需的有机热控涂层预研工作提出了几点建议。     

空间环境下的有机热控涂层

本文综述了国外在空间有机热控涂层领域中的研究工作和试验，着重分析了空间极端环境中紫外光辐照和原子氧侵蚀这两大因素对有机热控涂层的影响。     

TiO2-有机硅热控涂层对空间聚合材料的防护

在原子氧 (AO)地面模拟设备中对空间材料Kapton及TiO2 有机硅热控涂层进行原子氧剥蚀效应试验。用LAMBDA 9分光度计、光电子能谱 (XPS)、红外光谱 (FTIR)和扫描电镜 (SEM )研究了原子氧 (AO)对Kapton侵蚀机理及对其表面涂覆的TiO2 有机硅热控涂层的防护作用进行了表征。AO对Kapton表现了较严重的侵蚀作用 ,而所施用的TiO2 有机硅热控涂层的表面形貌则变化甚少 ,实验表明 ,该涂层对AO辐照有较强的防护效果、较好的空间稳定性和热控性能。     

热控涂层

本文介绍了热控涂层的热控原理，品种，空间稳定性及在卫星上的应用。     

低太阳吸收率αs,高发射率ε有机硅热控涂层进展

本文总结了有机硅热控涂层的设计原理及其紫外真空降解原因,评述了涂层的国内外进展.     

新型无机热控涂层的性能及应用

采用自制新型无机白色填料、无机黏结剂制备了高稳定无机热控涂层。对热控涂层的厚度、面密度、热辐射性能、真空挥发性、热循环性能、空间环境稳定性(真空-紫外、真空-质子、真空-电子、原子氧)及多种基材的适应性进行了测试与验证。结果表明:新型无机热控涂层的太阳吸收比≤0.07、半球发射率≥0.90、面密度200～360 g/m~2,经过地面模拟空间环境试验后涂层的太阳吸收比退化量较小,具有优异的空间环境稳定性,适用于多种基材表面。     

有翼高超声速再入飞行器气动设计难点问题

有翼高超声速再入飞行器是近年来的研究热点,气动设计是飞行器设计的关键。为了更清楚地认识有翼高超声速再入飞行器气动设计的难点问题,对有翼高超声速再入飞行器的发展、优势及总体任务剖面进行了介绍,从5个方面详细介绍了该类飞行器气动设计的难点问题,包括多约束复杂面对称气动布局设计、高温真实气体效应对气动特性影响、天地差异与天地换算方法、反作用控制系统(RCS)喷流干扰对气动特性的影响以及气动数据不确定度等,简要阐明了这些难点问题对总体设计的重要性以及初步的解决思路,为有翼高超声速再入飞行器气动设计提供了一些参考。     

Simulation and Analysis of Crashworthiness of Fuel Tank for Helicopters

Crashworthiness requirement of fuel tanks is one of the important requirements in helicopter designs. The relations among the protection frame, textile layer and rubber layer of the fuel tank are introduced. Two appropriate FE models are established, one is for an uncovered helicopter fuel tank without protection frame, and the other is for fuel tank with protection frame. The dynamic responses of the two types of fuel tanks impinging on the ground with velocities of 17.3 m/s are numerically simulated for the purpose of analyzing energy-absorbing capabilities of the textile layer and protection frame. The feasibility of the current crashworthiness design of the fuel tank is examined though comparing the dynamic response behaviors of the two fuel tanks.     

The effect of inlet conditions on the flow and heat transfer in multiple rotating cavity with axial throughflow

This paper discusses experimental results from two different build configurations of a heated multiple rotating cavity test rig.Measurements of heat transfer from the discs and tangential velocities are presented.The test rig is a 70% full scale version of a high pressure compressor stack of an axial gas turbine engine.Of particular interest are the internal cylindrical cavities formed by adjacent discs and the interaction of these with a central axial throughflow of cooling air.Tests were carried out for a range of non-dimensional parameters representative of high pressure compressor internal air system flows(Re up to 5×106 and Rez up to 2×105).Two different builds have been tested.The most significant difference between these two build configurations is the size of the annular gap between the(non-rotating) drive shaft and the bores of the discs.The heat transfer data were obtained from thermocouple measurements of surface temperature and a conduction solution method.The velocity measurements were made using a two component,LDA system.The heat transfer results from the discs show differences between the two builds.This is attributed to the wider annular gap allowing more of the throughflow to penetrate into the cavity.There are also significant differences between the radial distributions of tangential velocity in the two builds of the test rig.For the narrow annular gap,there is an increase of non-dimensional tangential velocity V/Ωr with radial location to solid body rotation V/Ωr=1.For the wider annular gap,the non-dimensional velocities show a decrease with radial location to solid body rotation.      

ν-gap度量及其在飞行控制律评估中的应用

 传统控制律评估方法主要用于单输入单输出（SISO）系统，且对模型参数摄动考虑不够全面,针对这些不足，研究了ν-gap度量方法。在介绍系统广义稳定裕度相关概念的基础上，给出了ν-gap度量的定义、特点和性质以及近似摄动模型的计算，提出ν-gap度量评估控制律的步骤。实例结果表明，该方法不仅克服了上述传统评估方法的缺陷，而且还有根据所求的各摄动影响情况忽略影响小的元素，以减少计算量及可以找到最坏情况下的参数摄动组合等优点。     

突破技术趋同，波音再现竞争优势

 波音公司面临着来自空客公司的巨大挑战,企业战略性创新才是公司成功的关键。为此波音公司的全部战略性研究集中在扩大产品的差异性上,体现在3个方面：电子化（e-Enabled）运营环境、整体复合材料机身部件的制造技术和支持波音787客机的全球协同环境（GCE）。     

临近空间飞行器测控与信息传输系统频段选择

 临近空间飞行器是高性能信息化武器平台,测控（TT&;C）与信息传输系统是其信息保障的核心,而选择合理、可行的频段是展开系统设计的前提和基础。频段选择影响到整个技术方案的制定,是一个需综合考虑、影响深远并具有战略意义的关键问题,从国际电联（ITU）国际标准、高速数传、接收信噪比（SNR）、“三抗”、超视距中继、黑障、雨衰以及设备研制成熟度8个方面全面、细致论证了近空间平台测控系统的频段选择问题,最终得出在视距链路中以Ka频段为宜,在超视距链路中以Ku/Ka双频段为宜的结论。     

基于弯曲激波压缩系统的高超声速进气道反设计研究进展

总结了近十年来弯曲激波压缩研究的主要成果。提出了弯曲激波压缩系统的新概念,即利用特殊设计的楔形弯曲压缩面或空间弯曲压缩面,产生一系列与前缘弱激波相互交汇或叠加的压缩波系,从而使前缘激波弯曲,形成特殊的弯曲激波,它与波后的等熵压缩波来共同完成对气流的压缩。在此基础上,实现了由给定出口气动参数的超声速内流道反设计,实现了由给定压缩面压力分布和给定压缩面马赫数分布要求的型面反设计,实现了由给定激波波面的压缩型面反设计。研究证明,弯曲压缩面-弯曲激波压缩系统具有良好的综合气动性能,为高性能高超声速进气系统的气动设计提供了一种全新的设计方法。     

Integrated Entry Guidance for Reusable Launch Vehicle

A method for the implementation of integrated three-degree-of-freedom constrained entry guidance for reusable launch vehicle is presented. Given any feasible entry conditions, terminal area energy management interface conditions, and the reference trajectory generated onboard then, the method can generate a longitudinal guidance profile rapidly, featuring linear quadratic regular method and a proportional-integral-derivative tracking law with time-varying gains, which satisfies all the entry corridor constraints and meets the requirements with high precision. Afterwards, by utilizing special features of crossrange parameter, establishing bank-reversal corridor, and determining bank-reversals according to dynamically adjusted method, the algorithm enables the lateral entry guidance system to fly a wide range of missions and provides reliable and good performance in the presence of significant aerodynamic modeling uncertainty. Fast trajectory guidance profiles and simulations with a reusable launch vehicle model for various missions and aerodynamic uncertain-ties are presented to demonstrate the capacity and reliability of this method.     

Experimental Study on Effects of Fuel Injection on Scramjet Combustor Performance

In order to investigate the effects of fuel injection distribution on the scramjet combustor performance, there are conducted three sets of test on a hydrocarbon fueled direct-connect scramjet test facility. The results of Test A, whose fuel injection is carried out with injectors located on the top-wall and the bottom-wall, show that the fuel injection with an appropriate close-front and centralized distribution would be of much help to optimize combustor performances. The results of Test B, whose fuel injection is performed at the optimal injection locations found in Test A, with a given equivalence ratio and different injection proportions for each injector, show that this injection mode is of little benefit to improve combustor performances. The results of Test C with a circumferential fuel injection distribution displaies the possibility of ameliorating combustor performance. By analyzing the effects of injection location parameters on combustor performances on the base of the data of Test C, it is clear that the injector location has strong coupled influences on combus- tor performances. In addition, an inner-force synthesis specific impulse is used to reduce the errors caused by the disturbance of fuel supply and working state of air heater while assessing combustor performances.     

(高)超声速流动试验技术及研究进展

近年来,与高速飞行器相关的(高)超声速流动受到了极大的关注。这类流动所具有的非定常性、强梯度和可压缩性对试验方法和风洞设计技术提出了挑战。超声速纳米示踪平面激光散射(NPLS)技术是由作者所在团队研发的非接触光学测试技术。它能够以较高的空间分辨率来揭示超声速三维流场的一个瞬态剖面的时间解析的流动结构。介绍了NPLS技术以及基于NPLS开发的密度场测量、雷诺应力测量和气动光学波前测量等方法,并回顾了这些技术在超声速边界层、超声速混合层、超声速压缩拐角、激波/边界层相互作用和光学头罩绕流等流动中的应用,清晰地再现了边界层、混合层、激波等典型流场结构及其时空演化特性。另外,为了模拟和研究高空大气条件下边界层自然转捩和超声速混合层的转捩特性,介绍了高超声速静风洞、超-超混合层风洞的设计技术以及层流化喷管的设计方法。