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半球谐振陀螺是一种基于哥式效应的固体波动陀螺,具有高精度、长寿命、高可靠性的优势,是未来陀螺的重要方向,国内外均开展了半球谐振陀螺的相关研究。本文对美国、俄罗斯、法国以及国内的半球谐振陀螺研究历程、技术及应用现状进行了介绍,在半球谐振陀螺技术发展过程中存在着加工制造难度大、动态范围小以及全角模式下存在角速度测量阈值等技术瓶颈,亟需突破高Q值材料、两件套陀螺加工制造以及全角模式控制等关键技术研究。半球谐振陀螺的未来发展方向包括高精度、大动态、低成本以及轻质小型化等,在航天、航海、战略战术武器等诸多领域上,半球谐振陀螺都将有着良好的应用前景。 相似文献
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半球谐振陀螺是具有精度高、质量小、寿命长等特点的新型固态陀螺,在航海、航空、航天等领域有着广泛应用前景。半球谐振陀螺的质量不均匀性调平技术是制造高精度半球谐振陀螺的关键技术。针对半球谐振陀螺质量不均匀性调平技术,首先对谐振子性能影响最大的四次谐波缺陷辨识方法及其关键性能指标发展现状进行了分析;其次,对影响谐振子性能的一次、二次、三次谐波缺陷辨识方法进行了归纳梳理;然后,总结分析了谐振子四类调平工艺——传统机械加工、化学刻蚀、激光刻蚀和离子束刻蚀的工艺方法及特点;最后,展望了谐振子调平技术待解决的问题及未来研究的重点。 相似文献
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《导航定位与授时》2019,(6)
正回顾半球谐振陀螺技术发展历史,应该说,美国诺格公司(含台尔柯、利顿阶段)发明并发展了半球谐振陀螺,而法国萨基姆公司(后合并为赛峰公司)赋予了半球谐振陀螺新的发展空间和机遇。2000年前后,萨基姆公司提出平面电极两件套方案,并在此基础上先后突破了全角控制、参数自校准、谐振子批量制造等关键难题,针对陆海空天多个应用领域研制了典型产品,特别是2018年发布了精度可达1海里/5天的战略级惯导系统,以至于该公司信心满满的宣称半球谐振陀螺将改变惯性技术版图,并对其进行大力商业推广。这一系列动作和成果引人瞩目,美、俄以及我国近年来重新关注半球谐振陀螺技术的发展,并投入了极大的研究热情。 相似文献
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有翼高超声速再入飞行器气动设计难点问题 总被引:2,自引:1,他引:2
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。 相似文献
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LUO Cheng LIU Hua YANG Jia-ling LIU Kai-xin 《中国航空学报》2007,20(3):230-235
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. 相似文献
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The effect of inlet conditions on the flow and heat transfer in multiple rotating cavity with axial throughflow 总被引:1,自引:0,他引:1
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. 相似文献
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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)。 相似文献
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临近空间飞行器测控与信息传输系统频段选择 总被引:7,自引:0,他引:7
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。 相似文献
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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 总被引:3,自引:0,他引:3
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。 相似文献
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Integrated Entry Guidance for Reusable Launch Vehicle 总被引:2,自引:2,他引:0
NING Guo-dong ZHANG Shu-guang FANG Zhen-ping 《中国航空学报》2007,20(1):1-8
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. 相似文献
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Wu Xianyu Li Xiaoshan Ding Meng Liu Weidong Wang Zhenguo 《中国航空学报》2007,20(6):488-494
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. 相似文献
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(高)超声速流动试验技术及研究进展 总被引:1,自引:1,他引:1
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。 相似文献