共查询到20条相似文献,搜索用时 187 毫秒
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为了研究蜗轮蜗杆装置的疲劳特性,设计了一套蜗轮蜗杆疲劳测试试验台,通过一系列试验能准确测量出蜗轮蜗杆的疲劳寿命;在此基础上建立该控制系统数学模型,并对控制系统进行MATLAB仿真;实验表明,其精度满足要求,并且系统工作稳定可靠. 相似文献
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基于LabVIEW的车辆冲击试验台测控系统设计 总被引:3,自引:3,他引:0
对应用于铁道机车车辆缓冲器及车体进行冲击试验的试验台测控系统进行了研究;基于LabVIEW技术,设计了车辆及其缓冲器冲击试验台的测控系统;对测控系统构成及原理进行了介绍,并描述了电机控制系统和软件功能;借助于计算机多功能接口卡,由计算机完成冲击试验台的轨道角度以及车辆的锁闭和释放控制,通过不同轨道角度的控制实现对不同的车辆冲击速度的控制,并可完成对车钩、缓冲器及车辆冲击应力的测试;最后进行的试验表明试验台达到了设计要求. 相似文献
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采用新型的封闭功率流齿轮试验台,对新型的圓弧齿轮传动的疲劳失效进行了试验。试验齿轮是不同螺旋角,相同纵向重合度的21对齿轮副。试验结果表明:齿面疲劳裂纹产生在单啮合线轮齿开始啮入的齿面上,裂纹扩展,蔓延到齿背直至轮齿局部或整体折断。还给出了圆弧齿轮的疲劳寿命与螺旋角、润滑油粘度及转速间的关系曲线,并进行了讨论。 相似文献
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房间空调器试验台测控软件的开发 总被引:1,自引:0,他引:1
为了能在各种环境条件下对房间空调器的性能进行测试,就需要专门的仿真设备.房间空调器试验台就是用于房间空调器的自动化仿真测试设备,可进行空调器的制冷能力、制热能力、一般性能试验、自动除霜试验、环境试验、异常试验等一系列仿真试验.测控软件是本试验台的核心组成部分和灵魂,对空调器的各种试验进行组织、监控和数据处理,是软件技术、制冷技术和测量控制技术的结合.该文介绍了房间空调器试验台的构成,用VB.net来开发房间空调器试验台测控软件,进行试验过程的自动化测量监控,并将测控软件应用到实际工业现场中,满足了空调器制造商对空调器质量检测和研究开发的需要. 相似文献
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在当前汽轮机的某些极限设计工况下,基于无限寿命的线弹性考核规范已经无法满足当前的工程设计要求,需要发展弹塑性强度计算方法以及有工程意义的强度评估准则,并在此基础上引入低周疲劳寿命考核方法对零部件寿命进行分析预测.对某汽轮机末级长叶片进行弹塑性有限元分析,提出将基于局部应力 应变法的低周疲劳分析理论与商用疲劳分析软件相结合的方法对叶片进行强度设计的方法和流程.结果表明:所提出的弹塑性分析以及疲劳寿命评估方法能很好地反映长叶片的实际强度,有助于进一步制定一套完善的适合工程应用的长叶片强度评估标准,从而提高叶片的设计水平. 相似文献
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直升机旋翼系统载荷和强度飞行试验是对真实大气环境中旋翼系统应力载荷谱的研究,它提供的真实数据是理论计算所不能提供的;因此旋翼系统载荷试飞是直升机设计定型试飞中极其重要的项目;针对直升机旋翼系统载荷测试技术需求,采用模块化、冗余度和高集成的设计理念,通过多信道无线传输设计等技术,将采集的动态载荷数据调制、发射与解调,实现了多通道、高带宽和精同步的旋翼系统载荷数据采集与监控;该技术对于直升机旋翼系统载荷试飞中遇到的类似问题具有一定的借鉴意义。 相似文献
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In this short paper,we have treated the aerodynamic performance of micro downwind rotor with coning soft blades experimentally.The test wind rotor has the tip diameter of 1.5 m and three two-dimensional NACA0018 blades of 0.15 m chord whose material is light,soft and pliable foam plastic for perfect safety.From the wind tunnel test,it is realized that the performance is manageable by the coning angle of the rotor blade.In the present case,an improvement of the performance in lower wind speeds is achieved by... 相似文献
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为实现直升机旋翼桨叶挥舞角的测量,提出了一种基于双目视觉的测量方法.首先,在直升机旋翼桨叶上均匀布置编码标记点,用已标定的双目摄像机对旋翼桨叶每隔一定角度采集标记点图像;其次,对左右摄像机图像上的标记点进行解码和匹配,得到标记点的左右图像视差,进而计算标记点三维坐标;再次,利用标记点在各个角度下的三维坐标,计算旋翼中心和转轴方向,建立旋翼坐标系;最后,在旋翼坐标系下,根据标记点静止与高速旋转时在同一角度下的三维坐标,计算挥舞角大小.利用风扇叶片进行仿真试验,结果验证了该方法具有自动化程度高和测量精度高的特点,可满足直升机旋翼桨叶挥舞角测量的要求. 相似文献
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转子系统常见于旋转机械装置中,在航空、电力、化工等工业和民用的诸多行业中发挥着重要作用.转子系统一般由轴和多级叶轮组成,存在强度、疲劳、振动和噪声等一系列问题,亟待通过优化设计等手段提高产品的各项性能.由于每级叶轮都含有由多条叶片构成的叶片组,因此在应用有限元等方法分析时,即便利用了回转周期的性质,转子系统的整体自由度数目依然庞大,优化设计的计算效率有待提高.为了提高转子系统分析的效率,可将根据气动性能要求设计的单级叶盘视为状态已经确定的子系统,在具备足够计算精度的前提下对其有限元模型进行缩聚或简化,以降低整体系统的自由度.文章介绍叶片组模型的等效建模方法,以固有振动特性相近为等效准则,将有限元模型中周向环绕的叶片组等效为变参数圆柱型正交各向异性环形板,并通过理论推导和计算得到了环板模型的几何与材料等物理参数.以航空发动机低压涡轮叶盘模型为例,实现了叶片组的模型等效过程.结果表明,等效方法可在保证精度的前提下大大降低模型的自由度数目,为后续整体转子系统的优化设计提供了高效的叶盘建模方法. 相似文献
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Mark W. Blackwell Owen R. Tutty Richard D. Sandberg 《International journal of control》2016,89(1):55-68
The inclusion of smart devices in wind turbine rotor blades could, in conjunction with collective and individual pitch control, improve the aerodynamic performance of the rotors. This is currently an active area of research with the primary objective of reducing the fatigue loads but mitigating the effects of extreme loads is also of interest. The aerodynamic loads on a wind turbine blade contain periodic and non-periodic components and one approach is to consider the application of iterative learning control algorithms. In this paper, the control design is based on a simple, in relative terms, computational fluid dynamics model that uses non-linear wake effects to represent flow past an airfoil. A representation for the actuator dynamics is included to undertake a detailed investigation into the level of control possible and on how performance can be effectively measured. 相似文献
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Turbine blades are the key aerodynamic parts and most widely used in turbomachinery. Rather than working individually, turbine blades are assembled on the rotor of turbomachinery to constitute bladed disks as the basic working units. Therefore, the quality of turbine blade assembly is crucial for guaranteeing the long and safe operation of turbomachinery with good performance. Aiming at this critical issue, two assembly error specifications of turbine blades are firstly defined as Circumferential Indexing Error and Axial Positioning Error, which are key factors affecting the throat and the incidence of turbine cascade. Then, the corresponding feature-based analysis methods are presented in this paper. Finally, the proposed theory and methods are experimentally verified through the bladed disk of a steam turbine rotor. The results demonstrate that the two defined assembly error specifications of turbine blades can be effectively extracted using the proposed methods. The assembly error of turbine blades can be used to evaluate the aerodynamic performance and the operating safety of turbine. Moreover, a guide can also be provided for the subsequent adjustment and correction of turbine blade assembly. 相似文献
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Jean-Jacques Chattot 《Computers & Fluids》2006,35(7):733-741
A helicoidal vortex model is used to predict the flow past the blades of a wind turbine. As the tip speed ratio (TSR) varies, the environment in which the blades operate varies, and for low enough TSR, the local angle of attack α will be larger than (α)Clmax, the incidence of maximum lift. The problem becomes highly nonlinear and it is shown that adding an artificial viscosity term to the equation allows the iterative algorithm to converge toward a smooth solution that is physically acceptable.The introduction of unsteady effects is useful to understand the cyclic forces and moments due to yaw or tower interaction, both for the design of blades to account for fatigue and for power output prediction. The 2-D impulsively plunging plate problem is solved with a semi-implicit scheme and the integral and numerical solutions compared and shown to be in excellent agreement. A 2-D test case to study the convection of a periodic shedding of vorticity downstream of a blade element is analyzed using the same semi-implicit algorithm and a stretched mesh similar to that used to model a turbine vortex sheet. The scheme captures accurately the vorticity distribution in the wake. Finally, the scheme is applied to the simulation of the NREL two-bladed rotor in yaw to assess the validity of the approach. 相似文献