半球谐振陀螺温漂误差补偿方法分析简述

半球谐振陀螺是一种具有惯导级性能的高精度固体振动陀螺,它基于哥氏振动原理,利用半球唇壳的径向振动驻波进动效应感测基座旋转。在陀螺的工作过程中,温度变化引发了振动频率、阻尼和耦合系数等的严重漂移。依据半球谐振陀螺的工作原理,重点讨论了温度漂移误差对半球谐振陀螺精度的影响及补偿方法。最后,对现阶段常用的温度误差补偿方法进行了总结,并对半球谐振陀螺温漂技术的发展趋势和应用前景进行了展望。     

半球动压马达转子端面垂直度检测装置

在半球动压马达转子端面垂直度的工序中,检测一直是影响生产效率的重要瓶颈问题,因没有理想的检测手段,目前只能依赖三坐标仪进行检测.因检测频繁、测点多、耗时长,极大地影响了生产效率.介绍了一种基于光学检测原理研制的端面垂直度检测装置,工程实际应用结果表明,它具有检测精度高、操作简便、时间短的特点,极大地提高了检测效率,在提高生产效率方面具有重大的实际意义.     

基于响应面设计的马达锥配结构参数仿真分析

利用响应面法设计仿真试验,研究动压马达转子体锥配连接结构3个因素(锥配斜度系数、锥配过盈量、薄壁厚度)对2个指标(球碗变形、锥配效果)的影响大小.通过因素影响力分析及响应面分析,得到各因素指标之间关系,并据此给出较优的转子体结构参数:薄壁厚度1.2mm、锥配斜度系数250、锥配过盈量3.9μm,对应球碗变形量0.122...     

高超声速非平衡流场多个振动温度模型的数值研究

利用数值求解热化学非平衡Navier-Stokes方程的方法,建立了考虑一个和多个振动温度的高超声速热化学非平衡流场的CFD计算程序,并对半球模型和球锥模型进行了数值计算,研究结果表明:(1)各个分子组分的振动温度分布于考虑一个振动温度模型的振动温度周围,即一个振动温度模型的振动温度是多个振动温度模型的各个分子组分振动温度的一种平均值;(2)在模型身部,振动温度的峰值高于平动温度的峰值;在模型近尾出现振动温度冻结并高于平动温度。     

半球谐振陀螺技术发展趋势

半球谐振陀螺 （Hemispherical Resonator Gyroscope, HRG）是一种高可靠、长寿命、高精度的振动陀螺,具有一系列独特优势,适宜于空间领域。简要叙述了半球谐振陀螺的工作原理,对半球谐振陀螺的优势和关键技术进行了阐述,介绍了国内外发展现状和国外主要应用方向,以及半球谐振陀螺技术的发展趋势。     

半球动压马达半球孔加工误差的分析与改进

本文分析了手工研配陀螺动压马达半球孔与轴配合间隙过程中,孔易出现的各种形状误差的原因。针对误差出现的原因,提出了选择合理的磨料配方,采取改进研具形状、材料等切实有效的方法,解决了半球孔与轴的关键研配工艺,这些方法在实际工作中被证明是有效可行的。     

基于流固耦合的斜激波冲击作用下曲壁板气动弹性分析

采用自主发展的双向流固耦合求解器,研究了斜激波冲击作用下曲壁板的气动弹性响应特性。曲壁板的几何非线性大变形运动方程采用有限差分法求解,流体控制方程基于有限体积法求解,双向流固耦合采用交错迭代算法。计算结果表明:当动压小于临界颤振动压时,曲壁板表现出静平衡状态,且随着动压的增大,壁板变形的非对称性越明显。当动压大于临界颤振动压时,壁板振动位移先增大后减小,最终达到稳定颤振状态,且该极限环颤振并不关于初始位置正负对称的。同时,随着动压的增大,壁板颤振的正向峰谷值、负向峰谷值和振幅均逐渐增大,颤振频率则逐渐减小。壁板振动响应规律并不随着壁板弯曲高度的改变而单调递增或递减,较小的弯曲高度可以降低壁板颤振临界动压值,但是当弯曲高度进一步增大后,由于气动非线性特性增强,准周期无规则运动状态被激发了出来,临界颤振动压迅速升高。     

半球轴承批量检测夹具的设计及应用

三坐标测量机是快速自动测量设备,其装夹工件环节产生的准备时间对测量效率的影响远比手动量仪大.因此在批量轮番生产方式下采取有效措施,缩短测量准备时间,对提高产品检测效率具有重要意义.针对动压马达半球轴承成批轮番生产检测的任务特点,在分析检测流程、零件结构以及测量机工作特点的基础上,设计了由孔系基础板及专用定位、支承、紧固件组成的半球轴承批量检测夹具,实现了工件离线快速装夹、缩短了测量准备时间.通过实际应用证明了此方法的有效性.     

超声波马达机理的研究

超声波马达是一种由超声振动而获得驱动力的新型电机。它利用作为定子的压电陶瓷振子,通过压电效应产生高频振动并依靠摩擦力来驱动压置在其上的转子运动。其特点;结构简单,且转速低,单位体积转矩大,响应性能良好,控制性能好,效率高。     

半球谐振陀螺在平台惯性系统中的应用研究

半球谐振陀螺作为新型振动陀螺, 具有长寿命、长稳定期、高精度等优 点,能显著提高惯性系统的性能。讨论了半球谐振陀螺的特点,分析了其误差模型,研 究了半球谐振陀螺在平台惯性系统的应用技术和方法,重点介绍了基于半球谐振陀螺的 平台稳定回路、框架归零回路和调平锁定回路设计,并通过试验样机进行了试验验证。     

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.      

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。     

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。     

Research on Auto-detection for Remainder Particles of Aerospace Relay Based on Wavelet Analysis

Aerospace relay is one kind of electronic components which is used widely in national defense system and aerospace system. The existence of remainder particles induces the reliability declining, which has become a severe problem in the development of aerospace relay. Traditional particle impact noise detection (PIND) method for remainder detection is ineffective for small particles, due to its low precision and involvement of subjective factors. An auto-detection method for PIND output signals is proposed in this paper, which is based on direct wavelet de-noising (DWD), cross-correlation analysis (CCA) and homo-filtering (HF), the method enhances the affectiv-ity of PIND test about the small particles. In the end, some practical PIND output signals are analysed, and the validity of this new method is proved.