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151.
34万吨级FPSO的中横剖面优化设计 总被引:4,自引:1,他引:4
以中横剖面的面积最小为目标函数,应用自适应步长随机搜索法,对34万吨级FPSO中横剖面进行了优化设计,并将规范设计结果和优化设计结果进行了比较,优化效果较好。 相似文献
152.
Unified Water Gravity Wave Theory and Improved Linear Wave 总被引:2,自引:0,他引:2
Fu Yuhua Senior Engineer Structural Engineering Department China Offshore Oil Development Engineering Corp. Beijing 《中国海洋工程》1992,(1)
- Based on Least Square Method, this paper presents variational principle for handling various water gravity wave theories and the unified water gravity wave theory was given. By using this variational principle of unified water wave theory, two kinds of improved linear waves were derived. The first one uses the same boundary conditions which were applied to derive 5-order Stokes wave. The second one uses the accurate boundary conditions (Eqs. 11 and 12). The two improved linear waves were compared with the existing linear wave. 相似文献
153.
苏厚熙 《海洋地质与第四纪地质》1993,13(1):65-72
乌石凹陷是北部湾盆地的一个以下第三系沉积为主的生油凹陷。主要生油层流沙港组泥页岩生油指标高、厚度大、分布面积广,具有丰富的油气源;在早第三纪已形成的四个局部构造带为有利的油气聚集场所。凹陷东部流沙港组存在高压异常,而凹陷西部存在流沙港组与涠洲组两套烃源岩。 相似文献
154.
- This article briefs how to improve the holding power of a drilling vessel's anchor and to remove those unreasonable structures by such a technology - underwater-explosion technology. The article gives details of the structure, characteristics and applications of a rocket-launched anchor; as well as the principle, properties, applications of directional explosion cutting. 相似文献
155.
Zhao Deting
Senior Engineer China Offshore Oil Development Engineering Corporation Beijing 《中国海洋工程》1995,(4)
Based on some mechanical principles, this paper presents a new way for simplifying the tower structure on the platform, i. e., substituting the three-dimensional tower structure by using beam elements. For the overall analysis of offshore platform, this method can not only save man- power and computer time, but also get better results. This paper introduces the equivalent-simplifying method and its application in engineering. 相似文献
156.
Fu Yuhua
Senior Engineer China Offshore Oil Development Engineering Corporation P. O. Box Beijing 《中国海洋工程》1995,(3)
- This paper presents the method of determining JONSWAP spectrum by using measured wave data. If Hs, Tz and Tc are the measured significant wave height, average zero-up crossing wave period and average period between wave crests respectively and let y = T Z / TC; this paper provides equation to solve y fromf(y,y) = 0. From the solutions of this equation and by using LSM, the expression relating y as a function of y (for 2.54相似文献
157.
A New Model for Ice Forces on A Conical Structure 总被引:1,自引:0,他引:1
The ice force is an important factor to be taken into account for offshore structures in cold regions, and the calculation method of the ice force is meaningful for the offshore structure design. The cone is now used as an optimal ice-resistant structure because it can cause bending failure of the ice sheet. The interaction between an ice sheet and a conical structure is studied in this paper and Croasdale‘s model is modified based on field observations. The newly built model separates the ice sheet into the emersed part and the floating part, and the equilibrium analyses are canied out respectively. The bending moment distribution of the ice sheet is analyzed for the determination of the position of bending failure, which serves as a supplementary restraint. The analytic solution of the ice foree on a conical structure is obtained it is verified with the experimental data of previous researches. 相似文献
158.
Chu Liangcheng Qu Naisi Guo Yonggang Lu Min Ph.D. Dalian University of Technology Dalian
Associate Professor Dalian University of Technology Dalian
Assistant M.S. Dalian University of Technology Dalian
Engineer Bohai Oil Company Tianjin 《中国海洋工程》1993,(4)
- Theoretically speaking, it is impossible to make the differential equation of motion uncoupled for the natural modes of a system in consideration of the attached water. The hydro-elastic structure is equal to the, non-proportional damping system. In this paper a perturbation analysis method is put forward. The structure motion equation is strictly solved mathematically, and the non-proportional damping problem is transformed into a series of proportional damping ones in the superposition form. The paper also presents the calculation formula of the dyanamic response of the structure being subjected to harmonic and arbitrary load. The convergence of the proposed method is also studied in this paper, and the corresponding convergence conditions are given. Finally, the proposed method is used to analyze the displacement response of a real offshore platform. The calculation results show that this method has the characteristics of high accuracy and fast convergence. 相似文献
159.
160.
应用地球化学方法评价断层的封闭性 总被引:8,自引:1,他引:7
断层的封闭性和连通性研究对于了解断层在油气成藏和石油开发中的影响具有重要的意义.根据断层附近油藏的地球化学特征, 可以研究排烃期断层的封闭性.在涠西南凹陷油田的研究工作中, 通过断层两端油层的化学组成指纹的差异, 证实了断层的存在, 虽然断距较小, 但仍影响了油藏的连通.对欧利坨子地区靠近断层的油藏分析表明, 本区的深大断裂可以作为油气的有效通道, 靠近断层油藏成熟度较高, 且含氮化合物较丰富.本研究提供的2个实例证实地球化学方法用于判断断层的封闭性有着不可替代的优越性. 相似文献