摘要：为理解超紧凑大S弯进气道与风扇的耦合效应,基于体积力模拟方法开展了一体化计算研究。研究的进气道长径比为2.5,使用rotor 67进行耦合分析,体积力模型与冻结转子计算得到的总压比、总温比和等熵效率分别相差4.49%,0.26%和2.38%。流场分析表明,风扇对入口段流场影响较为明显,主要体现为畸变区的顺向偏转与微弱衰减;进气道出口畸变经过风扇叶片后得到改善,大低压区和反向旋流基本消失;而流体在叶片的前后缘旋流角与轴向速度的综合改变量越大,风扇对气流做功越多。总的来说,超紧凑大S弯进气道与风扇之间耦合比较明显,需要在设计时进行详细的考察。

摘要：利用几何代数的多维统一性与运动表达的简明性特征,设计了用几何代数向量场拟合进行地表坡向表达和提取的新算法。基于高斯合成曲面模型模拟的多尺度格网DEM数据,对坡向计算的正确性、抗噪性及空间整体性进行验证和统计分析,显示几何代数向量场拟合方法能正确提取地表坡向,且较之三阶反距离平方权算法具有更强的抗噪性;选取5类典型的不同地貌类型数据进行最优窗口和坡向提取试验,黄土丘陵,梁、峁、塬和风沙地貌的最优窗口大小分别为13、11、11、11、17,所提取的坡向可以较好地反映不同地貌类型的结构特征。

摘要：The main advantage of tail-sitter unmanned aerial vehicle (UAV) are introduced. Three design solutions of rotor tail-sitter lift system of UAV have been presented and the respective control strategies and characteristics of three solutions are also analyzed in the paper, through the related experiments the design of twin-rotor lift system is verified, and its feasibility is proved. The characteristics and the applying background of the twin-rotor tail-sitter UAV are described in detail. Some useful conclusions of the lift system for tail-sitter UAV are obtained.

摘要：Small-scale vertical axis wind turbine (VAWT) rotor is developed for use in areas lacking adequate energy infrastructure. The materials and methods of construction are selected to minimize cost as much as possible. The paper describes the design of different kinds of vertical axis wind turbine rotors having different number of blades and twist angle. The aim of the work is to study the influence of the different designs on rotational speed and power of rotor in different wind speed.

摘要：以600 Wh飞轮储能系统为研究对象,为计算飞轮转子系统的临界转速分布及评估在高转速下运动稳定性,采用SolidWorks进行三维建模并导入有限元软件SAMCEF rotor求解其临界转速和模态振型。对飞轮储能系统进行升降速试验采集动态试验数据并通过时域图、频域图、轴心轨迹图进行分析。将有限元分析与试验数据进行对比,结果表明:飞轮转子系统在临界转速时振幅明显大于稳定转速时,在工作转速中,轴心轨迹重复性较好,没有超过气隙值0.3 mm,稳定性良好,为不同储能飞轮转子的改善和设计提供参考和依据。

摘要：An interactive computer aided preliminary design system has been developed mainly for gas turbine engine rotors. The design system covers three parts: disks, shafts and rotor dynamics. A nu- merical optimization package called MPOP is used to minimize the weight of disks, shafts and optimize the arrangement or stiffness of bearings for rigid or flexible rotors subjected to certain constraints of sizes, shapes, stresses, deflections, stiffness and frequencies. Various forms of disks, shafts, rotors and structure-analysing result curves are displayed on the screen. Designer may select, inspect or modi- fy the results interactively. The integrated design of structure, optimization, strength and rotor dynamics has improved design quality and reduced turnaround time during preliminary design phase of gas turbine engine develop- ment. As an example, a real preliminary design of an aeroengine turbine rotor is described.

摘要：飞轮转子系统的结构布局对其高速旋转的稳定性有至关重要影响,以600Wh飞轮储能转子系统作为研究对象,通过建模及理论分析得到了转动惯量比与旋转运动稳定性之间存在的关系,采用转子动力学专业分析软件SAMCEF rotor分析了两种不同转动惯量比转子的涡动频率振型,临界转速等。有限元分析结果和理论建模分析结果互为验证,结果表明:当转动惯量比接近1时,对工作转速超过一阶临界转速的飞轮转子系统,转动惯量比小于1时稳定性较转动惯量比大于1时更有优势,研究结果对以后大容量飞轮储能转子系统结构设计有重要参考依据。

摘要：Van Zante等首次提出了诱导涡的概念,在研究诱导涡与压气机叶尖流场的关系之前需要回答"诱导涡是否存在"这一问题。为此以跨音转子NASA rotor 35为研究对象,采用四种不同的网格配置在80%设计转速下进行单通道数值模拟。数值计算均捕捉到了流场的主要特征,与实验结果符合较好;但没有出现所谓的诱导涡,因此对叶尖区流场的关注焦点仍然可以集中在叶顶间隙泄漏流本身。尽管如此,近机匣壁网格不断加密还是会对泄漏流的轨迹产生影响;因此Van Zante等提出的用来评估壁面剪切层强弱的参数VD依旧具有参考价值,只是针对其物理意义的解释需要重新阐述。

摘要：针对飞轮储能系统升降速实验中极限转速为9300 r/min,小于飞轮储能的最高工作转速15000 r/min,这会大幅降低飞轮储能系统的最大储能量。为提高飞轮储能实验中极限转速,从结构设计角度出发,采用理论公式分析、SAMCEF rotor有限元仿真分析并结合实验数据来研究盘式飞轮转子和柱式飞轮转子的临界转速分布规律及其稳定性。分析发现,质量相同、结构不同的盘式飞轮转子其二阶临界转速远远超过柱式飞轮转子,两者的一阶临界转速相同。根据不同工作转速和储能量要求的飞轮转子,采取不同的结构方案,确保其达到工作转速要求并稳定运行。

摘要：Non-axisymmetric endwall is numerically investigated to suppress the secondary endwall flow in a HP turbine suction *** endwall contour is represented by a non-uniform rational B-spline *** solution spaces are designed by the rule of hypercube sampling through variation of nodal radial *** most effective endwall contour is obtained through screening all available samples with surrogate-based *** show that non axisymmetric endwall reduces the turbulence kinetic energy of the passage vortex by 5.5%and the total pressure loss 1.6%.Local heat transfer coefficient is lowered on the afore passage endwall surface with a certain increment on the aft passage *** averaged heat transfer coefficient is reduced.