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42.
大型半潜式钻井平台安全关键技术研究 总被引:1,自引:1,他引:0
BINGO—9000型平台是目前世界上最先进的第五代半潜式钻井平台,能在深海(工作水深3000m),恶劣气候海况(零下20℃、风速41m/s、浪高32m)下开采石油。以BINGO—9000型平台为例,介绍了平台结构和压载状态实时监测系统设计的关键技术问题,以及基于疲劳寿命分析的结构设计思想。展开了该平台波浪载荷的分析计算,在此基础上对主体结构进行了三维有限元强度分析。对平台特殊结构如K型管节点及支撑结构和立柱结构进行了强度分析和疲劳寿命分析。还研究了平台吃水数据采集、压载状态监测等技术。通过以上关键技术的研究,平台结构设计更趋安全可靠合理,既具有必需的强度储备,又可减轻结构重量。 相似文献
43.
J.F. Shriver H.E. Hurlburt O.M. Smedstad A.J. Wallcraft R.C. Rhodes 《Journal of Marine Systems》2007,65(1-4):3
A 1/32° global ocean nowcast/forecast system has been developed by the Naval Research Laboratory at the Stennis Space Center. It started running at the Naval Oceanographic Office in near real-time on 1 Nov. 2003 and has been running daily in real-time since 1 Mar. 2005. It became an operational system on 6 March 2006, replacing the existing 1/16° system which ceased operation on 12 March 2006. Both systems use the NRL Layered Ocean Model (NLOM) with assimilation of sea surface height from satellite altimeters and sea surface temperature from multi-channel satellite infrared radiometers. Real-time and archived results are available online at http://www.ocean.nrlssc.navy.mil/global_nlom. The 1/32° system has improvements over the earlier system that can be grouped into two categories: (1) better resolution and representation of dynamical processes and (2) design modifications. The design modifications are the result of accrued knowledge since the development of the earlier 1/16° system. The improved horizontal resolution of the 1/32° system has significant dynamical benefits which increase the ability of the model to accurately nowcast and skillfully forecast. At the finer resolution, current pathways and their transports become more accurate, the sea surface height (SSH) variability increases and becomes more realistic and even the global ocean circulation experiences some changes (including inter-basin exchange). These improvements make the 1/32° system a better dynamical interpolator of assimilated satellite altimeter track data, using a one-day model forecast as the first guess. The result is quantitatively more accurate nowcasts, as is illustrated by several model-data comparisons. Based on comparisons with ocean color imagery in the northwestern Arabian Sea and the Gulf of Oman, the 1/32° system has even demonstrated the ability to map small eddies, 25–75 km in diameter, with 70% reliability and a median eddy center location error of 22.5 km, a surprising and unanticipated result from assimilation of altimeter track data. For all of the eddies (50% small eddies), the reliability was 80% and the median eddy center location error was 29 km. The 1/32° system also exhibits improved forecast skill in relation to the 1/16° system. This is due to (a) a more accurate initial condition for the forecast and (b) better resolution and representation of critical dynamical processes (such as upper ocean – topographic coupling via mesoscale flow instabilities) which allow the model to more accurately evolve these features in time while running in forecast mode (forecast atmospheric forcing for the first 5 days, then gradually reverting toward climatology for the remainder of the 30-day forecast period). At 1/32° resolution, forecast SSH generally compares better with unassimilated observations and the anomaly correlation of the forecast SSH exceeds that from persistence by a larger amount than found in the 1/16° system. 相似文献
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45.
液化天然气(LNG)的海上运输 总被引:3,自引:0,他引:3
概括介绍了世界液化天然气(LNG)海上运输的发展,并对液化天然气海上运输链及其组成,以及当前世界液化天然气主要项目情况进行概述。 相似文献
46.
Hsien-Ter Chou 《Journal of Marine Science and Technology》1996,1(3):149-154
A study of the mixing behavior of liquid waste after ocean dumping is essential for the identification of dump sites, as well
as for impact assessment on the surrounding oceanic waters. The dilution of liquid waste in the wakes of ships at sea is explored
in this study, and the effects of the circumstances of the discharge operation such as the discharge rate, and the size and
speed of the vessel, and the oceanic parameters such as currents and turbulence level in the water column, are examined. the
mixing process is categorized into three stages: near-wake, far-wake, and long-term diffusion. Dilution rates in the three
stages are derived, based on the theories of diffusion and momentumless wakes. In the far-wake stage, the speed of the ship
is the most effective parameter in enhancing the dilution rate. The formulae for dilution rates in the farwake stage and for
long-term diffusion agree well with field measurements, while the well-known IMCO formula underestimates the dilution rate.
Presented at the International Conference on Technology for Marine Environment Preservation (MARIENV '95), Tokyo, Japan, September
24–29, 1995. 相似文献
47.
上海海洋工程产业现状和发展 总被引:1,自引:0,他引:1
为加块发展上海的海洋工程,对上海的海洋工程历史和现状作了调查研究,按照“十一五”规划以及上海的具体情况,对其未来发展方向作了展望。 相似文献
48.
在分析自航水雷对沉底稳定性和自航性能要求的基础上,提出了两种使自航水雷同时满足沉底稳定性与自航性能要求的方法,给出了相应的设计实例,并对设计结果进行了分析、讨论。 相似文献
49.
介绍12m前置出口客车JS6120GC底盘的布置、性能参数及结构特点,分析和解决设计中遇到的问题。 相似文献
50.