基于最小二乘支持向量机的工具误差分离与折合

制导工具误差分离与折合是导弹精度评定中的重要问题,提出了利用支持向量机方法获得工具误差系数估计和进行弹道误差折合的新方法,由于支持向量机综合考虑了结构风险和经验风险,使得模型的泛化能力增强。仿真计算表明,与最小二乘和主成分方法相比,最小二乘支持向量机获得的误差系数估计与真值更加接近,折合得到的全程弹道遥外差更加准确。     

转子叶尖间隙对高负荷压气机性能影响的数值计算和试验验证

为了研究高负荷压气机转子叶尖间隙对压气机性能的影响，采用数值模拟软件NUMECA对某4级压气机和其中的1个 典型级进行了不同间隙的计算。计算结果表明：当间隙超过叶高的0.52%后，叶尖流场出现堵塞，喘点压比衰减速度开始加剧，直 至5.24%性能衰减速度逐渐减弱；在多级环境中，4级压气机间隙增大叶高的0.5%，喘点压比降低了约0.6%～4.3%，间隙增大的叶 排作功能力降低是压气机喘点总压比降低的主要原因，其中前2级间隙增大对总性能影响较大。同时，通过4级压气机试验验证 了间隙对性能的影响，验证结果表明：间隙增大叶高的0.78%后，4级压气机喘点压比和峰值效率分别降低了1.4%和0.4%，在 65%～88%叶高时的压比和效率的性能衰减较为明显。     

Effective filtering of target glint

An effective filter structure is suggested for filtering of target glint in active homing engagements of a ship-to-ship missile. The proposed filter has decoupled range and angle channels so that it has a sound mathematical basis as well as computational efficiency as applied to the interacting multiple model algorithm. The proposed algorithm in conjunction with an impact angle control law is tested by a series of simulation runs and it is shown to have superior performance compared with the other filter structures     

TiC和ZrC颗粒增强钨基复合材料

用粉末冶金热压法制备了ＴｉＣｐ／Ｗ和ＺｒＣｐ／Ｗ两种钨基复合材料，对其高温强度进行了研究，结果表明，随着温度提高，两种复合材料的抗弯强度开始时逐渐提高，当ＴｉＣｐ／Ｗ复合材料达到１０００℃时有最大值１１５５ＭＰａ，ＺｒＣｐ／Ｗ复合材料在８００℃时最大值８２９ＭＰａ，分别比各自的室温强度提高５７％和１７％。而后，随温度的进一步提高，复合材料的强度又下降，分析了复合材料高温增强的机理。     

蜡纸存贮法在高超声速脉冲风洞舵-锥干扰流场显示中的应用

简述了蜡纸存贮法在高超声速脉冲风洞锥—舵干扰流场显示中的应用，给出了迎风面内舵周围干扰区立体和平面展开两种油流谱图，揭示了其三维干扰流动的特征。     

线圈法漏磁探伤的信号特性分析

本文由标量磁位计算圆柱形点缺陷的漏磁场，然后计算穿过式线圈及旋转式线圈探测点缺陷的漏磁场产生的感应电动势，分析这些检测信号的特性并得出相应的结论。     

过氧化氢／煤油发动机推力室气液燃烧数值模拟

采用离散相模拟颗粒随机轨道方法处理两相流动,采用SST后刊湍流模型,利用燃料的单步总反应模型模拟煤油蒸汽燃烧,针对过氧化氢／煤油发动机推力室,进行三维两相燃烧数值模拟。对推力室的总体流场特征及性能进行了初步研究,为开展进一步的数值研究奠定基础。     

Airfoil Aeroelastic Flutter Analysis Based on Modified Leishman-Beddoes Model at Low Mach Number

Based on modified Leishman-Beddoes (L-B) state space model at low Mach number (lower than 0.3), the airfoil aeroelastic system is presented in this paper. The main modifications for L-B model include a new dynamic stall criterion and revisions of normal force and pitching moment coefficient. The bifurcation diagrams, the limit cycle oscillation (LCO) phase plane plots and the time domain response figures are applied to investigating the stall flutter bifurcation behavior of airfoil aeroelastic systems with symmetry or asymmetry. It is shown that the symmetric periodical oscillation happens after subcritical bifurcation caused by dynamic stall, and the asymmetric periodical oscillation, which is caused by the interaction of dynamic stall and static divergence, only happens in the airfoil aeroelastic system with asymmetry. Validations of the modified L-B model and the airfoil aeroelastic system are presented with the experimental airload data of NACA0012 and OA207 and experimental stall flutter data of NACA0012 respectively. Results demonstrate that the airfoil aeroelastic system presented in this paper is effective and accurate, which can be applied to the investigation of airfoil stall flutter at low Mach number.     

Cf / E 预浸料先进拉挤固化工艺

为探索与预浸料先进拉挤成型技术相适应的工艺方案,采用DSC研究了碳纤维/环氧预浸料USN12500的固化放热过程,对USN 12500的典型固化工艺进行改进,以此为基础设计了不同压力和加压时机下的试验方案,采用实验室现有设备模拟先进拉挤过程制备了试样,以制品的孔隙率作为考察指标优选了的拉挤成型固化的工艺参数.结果表明:制品在110℃下处理20 min,热压阶段130℃下处理15 min同时保持0.4MPa的工艺压力,后固化150℃下处理1.5h为工艺试验的优化方案,并且能够制得孔隙率＜1.1％的制品.