摘要：This study proposed a design and optimization strategy for a tandem arranged cascade using the Non-dominated Sorting Genetic Algorithm(NSGA) Ⅱ multi-objective optimization algorithm and Back Propagation(BP) neural network technology. The NASA Stage 35 was employed as the initial bench mark in the present study and five geometric control parameters were working as the optimization parameters aiming to enhance the aerodynamic performance in terms of total pressure rise and efficiency. Results showed that the feasibility and capability of the proposed optimization strategy was successfully examined. In view of the fact that the initial tandem cascade(directly scaling down from NASA Stage 35) cannot guarantee the aerodynamic performance, first optimization trial was conducted to optimize the initial design. Results showed that the optimum can improve the flow quality whereas the separation on the blade is decayed or even eliminated particularly at the tip and root regions. However, compared with the initial tandem design, the enhancement in total pressure ratio(0.47%) and efficiency(1%) are too small to be noticed. Second investigation was particularly emphasizing on a high turning tandem compressor with an increment by 28°. The pressure rise and efficiency were augmented by 1.44% and 2.34%(compared to the initial tandem design), respectively. An important conclusion can be drawn that the optimization strategy is worthy to be used in high turning compressors with a considerable performance improvement.

摘要：以1台低速大尺寸轴流对转压气机为研究对象，利用布置在前/后转子叶顶的高频动态压力传感器阵列捕捉到其在不同转速配置和不同畸变条件下的失速初始扰动特征。通过分析在失速工况下采集到的压力波，得到的结果表明：当压气机来流均匀时，设计转速下的失速扰动类型为旋转失速，且传播方向与后转子旋转方向一致；当转速比为1.40时，成熟发展的失速扰动固定在周向某一位置，不沿周向旋转；随着前/后转子转速差进一步增大，转速比为1.52时的失速扰动类型又转变为旋转失速，但由于后转子对前转子尾迹的抽吸作用减弱，失速扰动传播方向与前转子转向一致。当改变压气机来流条件为周向进气畸变时，不同转速比下的失速扰动特征与均匀进气一致，但畸变会引起不同周向位置的失速前压力序列产生不同幅度的波动，利用联合经验模态分解-局部均值分解（EMD-LMD）方法捕捉到了随时间能量逐渐增强的失速前小扰动。

摘要：Swirl recovery vanes（SRVs） are a set of stationary vanes located downstream from a propeller, which may recover some of the residual swirl from the propeller, hoping for an improvement in both thrust and efficiency. The SRV concept design for a scaled version representing the Fokker 29 propeller is performed in this paper, which may give rise to a promotion in propulsive performance of this traditional propeller. Firstly the numerical strategy is validated from two aspects of global quantities and the local flow field of the propeller compared with experimental data, and then the exit flow together with the development of propeller wake is analyzed in *** kinds of SRV are designed with multiple circular airfoils. The numerical results show that the swirl behind the propeller is recovered significantly with Model V3, which is characterized by the highest solidity along spanwise, for various working conditions, and the combination of rotor and vane produced 5.76% extra thrust at the design point. However, a lower efficiency is observed asking for a better vane design and the choice of a working point. The vane position is studied which shows that there is an optimum range for higher thrust and efficiency.

摘要：涵道风扇是未来绿色航空动力的重要发展方向,快速、准确的涵道风扇设计方法成为工程领域的迫切需求。在传统的涵道风扇设计方法中,部件间的耦合效应需要建立在完善的三维数值计算或试验数据的基础之上。而本文发展了考虑涵道风扇关键部件耦合效应的设计方法,形成了涵道风扇一体化设计手段,并以此为基础开展了涵道风扇的一体化设计及验证工作。结果表明:相比于简单叠加设计方法,耦合设计使叶片推力设计误差由15%减小到3.5%;采用部件耦合方法设计的带有扩张喷管涵道风扇和等直径喷管涵道风扇的转静叶片推力设计误差满足工程需求,确认了部件耦合的设计方法正确传递了部件间的影响关系;通过试验对设计结果进行了推力校验,试验结果与设计点的总推力误差为1.25%,证明了本文发展的耦合设计方法的准确性。

摘要：明代通俗小说的兴盛与雕版印刷业的发展有重要关系。通俗小说刊刻起步于嘉靖年间,在万历时得到了迅猛发展,除了与印刷业的发展一致外,匠体字的运用也起到了重要作用。建阳刻书具有浓厚的商业气味,采用上图下文的插图方式,内容与印刷都比较粗陋,针对的是文化层次较低的读者。万历间江南民间出版业有了很大的发展,南京、苏州和杭州都是通俗小说出版的重要地区。到了天启、崇祯间,出版中心已逐渐转移到了这一带,这对通俗小说的装帧、题材及内容都产生了深刻影响。江南刻书开始重视书籍的质量,部分作品的插图、印刷都非常精美,成为可以独立欣赏的艺术品,同时某些具有较高素养的文人加入通俗小说的创作,也改变了通俗小说的美学风貌,呈现出文人小说的特点。

摘要：为寻找新的高活性农药 ,根据生物等排原理 ,设计合成了 10种未见文献报道的N′ 5 ( 1H 1,2 ,3 ,4 四唑基 ) N 芳甲酰基硫脲类化合物 .它们的结构经IR ,1HNMR和元素分析确证 .初步的生物活性测定结果表明 ,部分化合物具有优良的除草活性或植物生长调节活性 .

摘要：以设计的某对转压气机级为研究对象,应用F INE/TURBO和CFX软件研究了设计转速、典型工作状态下该压气机的性能和流场细微结构,为进一步优化对转压气机叶片设计提供了依据。计算结果表明:在压气机中反向旋转转子叶片布局设计较好的前提下,对转技术可以在较小的空间里实现较高的压比,从而大幅度提高发动机的推重比;文中给出的对转压气机设计局部流场结构还未达到最优,三维叶片还需要进一步改进,主要表现在一级转子根部和尖部附面层较厚,并伴随有分离现象;二级转子尖部分离流动强烈,使得下游叶片来流发生较大畸变;出口导叶设计尚不理想,集中表现为在根部和尖部有较弱的分离流。

摘要：为提高压气机串列叶栅复杂气动构型优化设计的效率,本文基于本征正交分解(POD)理论,建立了集几何外形参数化、样本空间降维、气动性能求解、降维模型构建和遗传算法寻优于一体的串列叶栅高效优化设计系统,针对叶型型面和叶片相对位置关系参数,开展了多目标优化设计工作。在7°攻角工况下,优化后的串列叶栅的静压升提高了0.53%,总压损失系数下降了9.25%,其他攻角条件下叶栅性能同样也得到了改善。与传统CFD方法相比,极大提高了优化效率,与基于Kriging代理模型相比,本文发展的优化系统由于缩小了设计变量空间,提高了优化的迭代效率,收敛耗时仅为Kriging代理模型的0.0796%。此外,基于POD方法的优化设计系统具有更高的建模精度,使串列叶栅获得了更高的静压升和更低的总压损失系数。优化后的串列叶栅节距系数增大、弯角比减小,减小了掺混损失,抑制了流动分离,改善了全攻角范围内的气动性能。

摘要：真实环境中得到的图像常会受到多种模糊降质过程的影响,导致成像质量下降,为此提出一种图像退化模型及相应的复原算法.与传统的级联方式不同,该算法假定模糊核函数是散焦与运动模糊的加权和形式;在散焦模糊给定的情况下,使用广义拉普拉斯分布作为运动模糊的统计模型,并在期望最大化(EM)算法框架下估计模糊核函数;最后利用估计的模糊核函数进行图像复原.实验结果表明,采用文中的复原算法能够较为准确地辨识出模糊核,提升了图像复原的效果.

摘要：为研究航空发电机匹配风扇设计的实用性方法,通过相应的实验装置,对某型航空发电机进行了风阻特性实验。通过强迫通风实验测得发电机不同状态下的风阻、流量及温升,根据实验结果及该发电机设计要求,利用正交设计方法设计出一种宽弦、大转折角、高稠度的轴流冷却风扇,同时设计了特殊的扩张轮毂结构,以进一步提高冷却性能。对加装设计风扇的发电机进行实验,验证了该风扇适用于该发电机冷却系统的高压差、小流量工况。