大型油轮舯剖面结构的优化设计

本文用直接计算法对给定了主尺度、船型、总布置和材料的大型油轮的舯剖面的纵向构件设计进行了优化。     

磨耗车轮与曲线钢轨接触关系

利用轮轨型面测量仪测量了SS4机车JM3型磨耗车轮型面和小半径曲线钢轨型面,采用样条曲线拟合方法获得了车轮几何型面,选取5种不同磨耗程度的车轮型面,建立了三维轮轨接触有限元模型,计算了轮轨接触斑面积和接触应力.计算结果表明:4型车轮与磨耗钢轨接触时,接触斑面积最小,仅为183 mm2,Von Mises应力最大值为1 ...     

深水立管法兰接头的有限元分析

针对深水立管法兰式接头,提出一种确定螺栓预紧力的方法,并采用有限元法对其进行了强度分析。考虑到接头的几何不对称性,采用三维整体建模,通过ANSYS软件的预紧单元模拟螺栓的预紧行为,使用接触单元模拟各部件之间的相互作用。按照API规范对接头的等效膜应力、等效弯曲应力与许用应力进行校核。在接头整体分析的基础上,建立螺纹的二维轴对称模型,进行局部应力分析。计算中使用参数建模法,法兰接头、螺纹的几何尺寸、材料性质和载荷等均可方便地更改。     

Fluid-structure coupled analysis of underwater cylindrical shells

Underwater cylindrical shell structures have been found a wide of application in many engineering fields, such as the element of marine, oil platforms, etc. The coupled vibration analysis is a hot issue for these underwater structures. The vibration characteristics of underwater structures are influenced not only by hydrodynamic pressure but also by hydrostatic pressure corresponding to different water depths. In this study, an acoustic finite element method was used to evaluate the underwater structures. Taken the hydrostatic pressure into account in terms of initial stress stiffness, an acoustical fluid-structure coupled analysis of underwater cylindrical shells has been made to study the effect of hydrodynamic pressures on natural frequency and sound radiation. By comparing with the frequencies obtained by the acoustic finite element method and by the added mass method based on the Bessel function, the validity of present analysis was checked. Finally, test samples of the sound radiation of stiffened cylindrical shells were acquired by a harmonic acoustic analysis. The results showed that hydrostatic pressure plays an important role in determining a large submerged body motion, and the characteristics of sound radiation change with water depth. Furthermore, the analysis methods and the results are of significant reference value for studies of other complicated submarine structures.     

200km/h交流传动电力机车辅助变流柜结构仿真

为了确保辅助变流柜柜体结构设计的合理和使用的安全,在详细分析200 km/h交流传动电力机车辅助变流柜结构特点的基础上,利用有限元分析软件对其进行了虚拟样机结构仿真分析,分析结果表明柜体初始设计方案局部结构的最大等效应力超过了材料的许用应力,因此对柜体结构强度薄弱部位进行了合理的改进,并满足了规范要求,其研究成果为辅助变流柜的研制开发提供了一定的理论依据.     

节流脉冲火焰原子吸收法测定人体胎盘血清中微量元素

用节流脉冲火焰原子吸收法测定了人体胎盘血清中的铜、铁和锌，方法快速、灵敏和精确，样品用量少，对于不易多得的生物样品分析提供了简便方法。     

FPSO锚泊系统动力响应影响因数分析

基于三维势流理论,建立了FPSO与锚泊系统时域耦合分析方法。在时域内对设计好的锚泊系统进行动态分析,并验证了锚泊系统设计的安全性。然后对比研究了系泊线夹角、预张力、转塔位置、拖曳力系数等重要参数对FPSO锚泊系统动力响应的影响,并讨论了悬链线式和张紧式两种系泊方式的区别。总结出了这些参数的影响规律,为锚泊系统动力响应的优化提供了参考意见。     

深水起重铺管船横摇运动性能分析(英文)

For a large floating vessel in waves,radiation damping is not an accurate prediction of the degree of roll unlike other degrees of freedom motion.Therefore,to get the knowledge of roll motion performance of deepwater pipelay crane vessels and to keep the vessel working safety,the paper presents the relationship between a series of dimensionless roll damping coefficients and the roll response amplitude operator(RAO).By using two kinds of empirical data,the roll damping is estimated in the calculation flow.After getting the roll damping coefficient from the model test,a prediction of roll motion in regular waves is evaluated.According to the wave condition in the working region,short term statistics of roll motion are presented under different wave parameters.Moreover,the relationship between the maximal roll response level to peak spectral wave period and the roll damping coefficient is investigated.Results may provide some reference to design and improve this kind of vessel.     

海洋立管涡激振动抑制装置模型试验研究

本文提出三种不同的涡激振动抑制装置设计方案：扰流纤维抑制装置、反向耦合单组双螺旋叶片式抑制装置以及反向耦合双组双螺旋叶片式抑制装置,分别对其进行试验研究,对比分析各模型的振动特性和抑制效果。实验结果表明：所设计的涡激振动抑制装置,均能在一定程度上降低立管的涡激振动响应。从抑制效果来看,对称来流情况下的双组双螺旋装置的效果最佳,其次为单组双螺旋装置和长扰流纤维装置,而短扰流纤维装置和非对称迎流情况下双组双螺旋装置的效果较差。对称来流和非对称迎流情况下的双组双螺旋装置是相同的,因此,采用双组双螺旋装置时,应根据海域的长期洋流方向,合理地布置该装置,使其最大限度地发挥抑制作用.     

SPAR平台上部模块就位安装过程的碰撞响应分析(英文)

In order to assess the possible collision effect, a numerical simulation for the upper module and spar platform docking at the speed of 0.2 m/s was conducted by using the software ANSYS/LS-DYNA, and the time history of the collision force, energy absorption and structural deformation during the collision was described. The purpose was to ensure that the platform was safely put into operation. Furthermore, this paper analyzes different initial velocities and angles on the Von Mises stress and collision resultant force during the docking collision. The results of this paper showed that the docking could be conducted with higher security. The data in this paper can provide useful references for the determination of the upper module's offshore hoisting scheme and practical construction by contrasting the numerical simulation results of the parameters on the docking collision.