柔性立管整体分析(英文)

The mechanical performance of a flexible riser is more outstanding than other risers in violent environmental conditions. Based on the lumped mass method, a steep wave flexible riser configuration attached to a Floating Production Storage and Offloading (FPSO) has been applied to a global analysis in order to acquire the static and dynamic behavior of the flexible riser. The riser was divided into a series of straight massless line segments with a node at each end. Only the axial and torsional properties of the line were modeled, while the mass, weight, and buoyancy were all lumped to the nodes. Four different buoyancy module lengths have been made to demonstrate the importance of mode selection, so as to confirm the optimum buoyancy module length. The results in the sensitivity study show that the flexible riser is not very sensitive to the ocean current, and the buoyancy module can reduce the Von Mises stress and improve the mechanical performance of the flexible riser. Shorter buoyancy module length can reduce the riser effective tension in a specific range of the buoyancy module length when other parameters are constant, but it can also increase the maximum curvature of the riser. As a result, all kinds of the riser performances should be taken into account in order to select the most appropriate buoyancy module length.     

基于ITOC的船舶管系生产进度控制系统研究(英文)

Manufacturing of ship piping systems is one of the major production activities in shipbuilding. The schedule of pipe production has an important impact on the master schedule of shipbuilding. In this research, the ITOC concept was introduced to solve the scheduling problems of a piping factory, and an intelligent scheduling system was developed. The system, in which a product model, an operation model, a factory model, and a knowledge database of piping production were integrated, automated the planning process and production scheduling. Details of the above points were discussed. Moreover, an application of the system in a piping factory, which achieved a higher level of performance as measured by tardiness, lead time, and inventory, was demonstrated.     

海洋中晕船问题的案例研究(英文)

Motion sickness is one of the main reasons why travelling by sea becomes a bad memory for a number of people, mainly due to a nauseating symptom. The aim of this paper is to characterize a condition called seasickness that has affected many people from a mathematical and psychological point of view. Based on the mathematical characterization, an existing model will be reviewed and described. In the psychological aspects, a statistical study of two hundred and thirteen people was performed in order to provide a comprehensive view of the different psychological factors affecting the passengers. Motion sickness also impacts onboard safety, as it reduces the effectiveness and the operating capability of the crew when responding to hazardous situations.     

集束塔式立管总体强度分析(英文)

Bundled hybrid offset riser (BHOR) global strength analysis, which is more complex than single line offset riser global strength analysis, was carried out in this paper. At first, the equivalent theory is used to deal with BHOR, and then its global strength in manifold cases was analyzed, along with the use of a three-dimensional nonlinear time domain finite element program. So the max bending stress, max circumferential stress, and max axial stress in the BHOR bundle main section (BMS) were obtained, and the values of these three stresses in each riser were obtained through the "stress distribution method". Finally, the Max Von Mises stress in each riser was given and a check was made whether or not they met the demand. This paper provides a reference for strength analysis of the bundled hybrid offset riser and some other bundled pipelines.     

拖曳线列阵声呐的研究现状与发展趋势(英文)

对反潜技术的需求促进了拖曳线列阵技术的发展,拖曳线列阵反潜技术的快速发展,使其越来越成为现代反潜战中不可或缺的技术。因此,有必要追踪了解国内外拖曳线列阵的研究现状,并预测拖曳线列阵技术的发展趋势。     

耦合非线性三维海洋立管的边界控制(英文)

This paper presents a design of boundary controllers implemented at the top end for global stabilization of a marine riser in a three dimensional space under environmental loadings. Based on the energy approach, nonlinear partial differential equations of motion, including bending-bending and longitudinal-bending couplings for the risers are derived. The couplings cause mutual effects between the three independent directions in the riser’s motions, and make it difficult to minimize its vibrations. The Lyapunov direct method is employed to design the boundary controller. It is shown that the proposed boundary controllers can effectively reduce the riser’s vibration. Stability analysis of the closed-loop system is performed using the Lyapunov direct method. Numerical simulations illustrate the results.     

地埋管换热器的数值模拟研究

文中阐述了地埋管换热器数值模拟研究中将要涉及的一些传热理论,并根据这些理论建立出单根U型地埋管换热器的数值模型。再结合上海地区工程实例模拟了地埋管换热器与周围土壤的换热过程,通过分析不同条件下的地埋管换热器四周温度场的分布情况,总结出土壤导热系数、孔隙度、每米孔深的平均放热量以及地下水的渗流速度对四周温度场的影响。     

水下采油树界面研究(英文)

介绍了水下油气行业中水下采油树的主要界面。论述了各界面相应的要求。对水下采油树同一界面中的两种接头进行了对比,探讨了这两种接头的优缺点,并结合实际经验提出了这两种接头的适用环境。     

深水SCR立管触地区域管土作用研究进展(英文)

钢悬链线立管作为一种全新的深水立管系统已经在国外多个项目中应用,总结了有关深水钢悬链线立管触地区域管土相互作用的研究进展,主要包括STRIDE和CAluSIMA工业合作计划的研究数据和其他的相关论文,能够为国内深水钢悬链线立管的研究提供参考.     

双螺旋折流板换热器最佳螺旋角的研究

为了研究换热器的传热性能与双螺旋折流板换热器的螺旋角的关系，通过建立多个不同螺旋角的管壳式换热器模型，运用数值计算的技术手段对其进行模拟，并对其数值模拟结果进行对比分析。结果表明：双螺旋折流板换热器存在最佳螺旋角使得换热器的换热性能最优。相同换热器结构的条件下，壳程进口流量对双螺旋折流板换热器的最佳螺旋角没有影响。随着壳径的增大，双螺旋折流板式换热器的最佳螺旋角有下降趋势。     

中国视窗(英文)

Pollution prevention regulations of Chi- nese ships due to take effect in July 2007The Regulations on Management of Safe Operation and Pollution Prevention re- cently promulgated by China MSA stipu- lates that the third stage ships must ob- tain safety ma…     

ROV空间运动仿真研究(英文)

In order to analyze the spatial maneuverability of the remotely operated underwater vehicle(ROV),the 6-DOF motion mathematic model of the ROV was founded.Hydrodynamics were analyzed by using the Taylor series.The thrusters on the ROV were discussed.This paper considers three cases of motion simulation:vertical motion,rotational motion and Z-shape motion.A series of simulation experiments showed that the 6-DOF motion mathematic model was correct and reliable,and also fit with the scene simulation.     

海上风力机安装技术研究(英文)

Wind power has made rapid progress and should gain significance as an energy resource, given growing interest in renewable energy and clean energy. Offshore wind energy resources have attracted significant attention, as, compared with land-based wind energy resources, offshore wind energy resources are more promising candidates for development. Sea winds are generally stronger and more reliable and with improvements in technology, the sea has become a hot spot for new designs and installation methods for wind turbines. In the present paper, based on experience building offshore wind farms, recommended foundation styles have been examined. Furthermore, wave effects have been investigated. The split installation and overall installation have been illustrated. Methods appropriate when installing a small number of turbines as well as those useful when installing large numbers of turbines were analyzed. This investigation of installation methods for wind turbines should provide practical technical guidance for their installation.     

操作与悬挂工况下的深海立管有限元分析(英文)

近年来,在深海进行油气开发的技术进展日新月异,全世界的海洋工程公司都在用更新的科技手段努力向更深的海域拓展,向深海进军已经成为了整个海洋行油工业的总体趋势.作为连接、平台设备和海底的重要设备,深海海洋立管的设计和使川也越来越趋向标准化.该文以某深海立管为例,从操作工况和悬挂工况两个方面探讨了钻井立管的整体分析中遇到的主要问题并进行了相关的校核.该文的具体上作包括计算了立管在钻探模态下的旋转角度和应力分布,确定了操作半径、浮箱数日等要素,并根据API规范进行了校核.根据计算的结果可以看出,所选的立管在恶劣海况下的操作半径相对较小,而确定的浮箱数略多,相关结论对立管的初步设计具有较好的参考意义.     

新概念认知声纳初步研究(英文)

The performance of a sonar system is closely related to the marine environment and the target characteristics. When dealing with the echoes of a traditional active sonar system, the sonar designers often do not take into account the influence of the environmental information and prior knowledge perceived by sonar receivers, making it difficult to obtain desired processing results. Based on the basic principle and key technology of sonar, this paper proposed a cognition-based intelligent sonar system in theory--cognitive sonar. Cognitive sonar is capable of jointly optimizing the transmission waveform and receiver according to the changes of environment so that its detection and identification performance can be significantly improved.     

水筒中直线涡运动的理论探讨(英文)

本文讨论了正方形截面水筒中直线涡的运动。当涡线不位于水筒中心线上时,数值计算表明,涡线在水筒截面平面上将沿近似螺旋线的轨迹运动。若涡线接近水筒中心线,则轨迹接近圆。文章详细分析了位于水筒中心线直涡线的运动稳定性,其结论是除了零波数的扰动,在其他任何波数的扰动下,涡线总可保持在水筒中心线上。对于零波数扰动,则与不位于水筒中心线的涡线运动情况一样,将逐步偏离水筒中心。     

波浪作用下沉管隧道管段沉放过程的频域响应(英文)

大型沉管隧道管段的沉放是沉管隧道施工中的关键环节之一.为了解沉管隧道管段沉放过程中的运动特性,对双驳船施工沉放的沉管隧道管段进行了频域计算分析.基于线性波理论和三维分布源法,计算得到波浪作用下沉管管段沉放过程中的波浪荷载及频域运动响应.计算中假定驳船本身的运动较小,忽略了驳船的运动对管段运动响应的影响,缆绳作用力由静力学方法计算.计算结果表明,沉管受到的波浪荷载在靠近水面的位置较大,并随着沉管沉放深度的增加而减小;随着波浪周期的增大,沉管受到的波浪荷载先增大而后减小;沉管的运动响应一般在离水面近的位置较大,并随着沉放深度的增加而减小.     

MARPOL附则Ⅵ(英文)

2011年7月11日至15日,第62届海洋环境保护委员会(MEPC)在伦敦召开,国际海事组织(IMO)通过了几项国际防止船舶污染海洋公约(MARPOL)修正案,包括通过了强制性的国际航行船舶温室气体减排措施规定。会议通过了新的第4章,MARPOL附则VI,并计划于2013年1月实施。该附则号召所有400gt及以上的新造船应取得国际能源效率证书及采用的"Attained EEDI"(能源效率设计指标)应不大于最大容许"Required EEDI"。Required EEDI基线值为7类船舶限定了总载重量,分别是散货船、燃气油轮、油轮、化学品船、有害液体集装箱船、杂货船、冷藏货船及多用途船。     

深水SPAR平台截断技术研究(英文)

To solve the dimensional limitations of physical models in tests, an equivalent water depth truncated design for a classical SPAR working in 913 m water was investigated. The water depth was reduced to 736m and then to 552m. As this was done, the mooring line lengths, EA value, and mass per meter were adjusted. Truncation rules and formulas for parameters and truncation factors were proposed. SPAR static characteristics were made to be consistent with those at full water depth. Then further time-domain coupled analysis was carried out for the SPAR when the mooring system experienced waves. The mooring lines were simulated by quasi-static method. Global responses and mooring line forces were found to agree well with test results for a prototype at that water depth. The truncation method proved to be robust and reliable.     

水下拖缆抛物构型分析研究(英文)

This article discusses the dynamic state analysis of underwater towed-cable when tow-ship changes its speed in a direction making parabolic profile path. A three-dimensional model of underwater towed system is studied. The established governing equations for the system have been solved using the central implicit finite-difference method. The obtained difference non-linear coupled equations are solved by Newton's method and satisfactory results were achieved. The solution of this problem has practical importance in the estimation of dynamic loading and motion, and hence it is directly applicable to the enhancement of safety and the effectiveness of the offshore activities.