共查询到20条相似文献，搜索用时 15 毫秒
1.
The demand for high-speed craft (mainly catamarans) used as passenger vessel has increased significantly in the recent years. Looking towards the future and trying to respond to the increasing requirement, high-speed crafts international market is passing through deep changes. Different types of high-speed crafts are being used for passenger transport. However, catamarans and monohulls have been the main choice not only for passenger vessel but also as ferryboat.Generally speaking, the efficient hydrodynamic hull shapes, engine improvements, and lighter hull structures using aluminum and composite materials make possible the increase in cruising speed.The high demand for catamarans are due to its proven performance in calm waters, large deck area compared to monohull crafts and higher speed efficiency using less power. Although the advantages aforementioned, the performance of catamaran vessels in wave conditions still needs to be improved.The high-speed crafts (HSC) market is demanding different HSC designs and a wide range of dimensions focusing on lower resistance and power for higher speed. Therefore, the hull resistance optimization is a key element for a high-speed hull success.In addition to that, trade-off high-speed catamaran (HSCat) design has been improved to achieve main characteristics and hull geometry. This paper presents a contribution to HSCat preliminary design phase. The HSCat preliminary design problem is raised and one solution is attained by multiple criteria optimization technique.The mathematical model was developed considering: hull arrangement (area and volume), lightweight material application (aluminum hull), hull resistance evaluation (using a slender body theory), as well as wave interference effect between hulls, calculated with 3D theory application. Goal programming optimization system was applied to solve the HSCat preliminary design.Finally this paper includes an illustrative example showing the mathematical model and the optimization solution. An HSCat passenger inland transport in Amazon area preliminary design was used as case study. The problem is presented, the main constrains analyzed and the optimum solution shown. Trade off graphs was also included to highlight the mathematical model convergence process. 相似文献
2.
This paper presents a new procedure for the optimization of the mooring design of floating platforms, in which an automatic design sequence is also established. Regarding the optimization philosophy, the following aspects are dealt with:
- • The optimization of the platform heading and its mooring pattern, taking into account the environmental force spreading;
- • optimum line length or line tension for each mooring line, associated to the optimization of the mooring line materials and sizes.
3.
The Next Generation Subsea Production System (NextGen SPS) is a new concept for petroleum development in ultra-deep water (UDW) areas. It can improve the structural performance of riser as well as provide several operational benefits to subsurface well completion (SWC) equipment. The design of NextGen SPS’s riser system which includes rigid riser and flexible jumper—like the free standing hybrid riser (FSHR), is a very important issue for the definition of NextGen SPS. This paper details an optimization design on the NextGen SPS’s riser system, with the assistance of the design of experiments (DOE) and surrogate model techniques. The optimization model pertaining to riser system is formulated firstly. The DOE is a statistical technique that guides a sensitive study on the behavior of the riser system before the optimization analysis. Structural responses are obtained by the fully coupled methodology. Through such a preliminary study, the effective contribution of each design variable at the riser performance will be known and some general conclusive remarks will be obtained. Based on the DOE results, design variables are screened to improve the efficiency of optimization process. Particle swarm optimization (PSO) method is employed to conduct the optimization analysis. In this analysis, surrogate models, which are developed by back propagation neural network (BPNN), replace the time consuming dynamic analysis to predict structural responses. Latin hypercube sampling (LHS) method is adopted to generate training sample and testing sample for the BPNN. NextGen SPS that operates at a depth of 3000 m is used as the case for this investigation. The efficiency of optimization design is improved by DOE and surrogate techniques, and a reduction of approximately 46% for the riser system cost is achieved. The obtained conclusions have applicability in reference to the engineering design of FSHR and the study procedure will provide reference for study on other new structure concept. 相似文献
4.
The concrete-steel platform structure is rather complicated because it involves such materials as concrete, reinforcing bars, steel, and so on. K the traditional dimension optimization method is employed, the optimal design of the platform will meet many handicaps, even it cannot be implemented at all. The multilevel optimal design approach is an efficient tool for the solution of large-scale engineering structures. In this paper, this approach is applied to the optimal design of a concrete-steel platform, which is formulated as a system level optimal design problem and a set of uncoupled substructure level optimal design problems. The process of optimization is a process of iteration between system level and substructure level until the objective function converges. An illustrative example indicates that this method is effective in the optimal design of concrete-steel platforms. 相似文献
5.
Optimal Design of Equivalent Water Depth Truncated Mooring System Based on Baton Pattern Simulated Annealing Algorithm简 总被引：2，自引：2，他引：0
The highest similarity degree of static characteristics including both horizontal and vertical restoring force-displacement characteristics of total mooring system, as well as the tension-displacement characteristics of the representative single mooring line between the truncated and full depth system are obtained by annealing simulation algorithm for hybrid discrete variables （ASFHDV, in short）. A“baton” optimization approach is proposed by utilizing ASFHDV. After each baton of optimization, if a few dimensional variables reach the upper or lower limit, the boundary of certain dimensional variables shall be expanded. In consideration of the experimental requirements, the length of the upper mooring line should not be smaller than 8 m, and the diameter of the anchor chain on the bottom should be larger than 0.03 m. A 100000 t turret mooring FPSO in the water depth of 304 m, with the truncated water depth being 76 m, is taken as an example of equivalent water depth truncated mooring system optimal design and calculation, and is performed to obtain the conformation parameters of the truncated mooring system. The numerical results indicate that the present truncated mooring system design is successful and effective. 相似文献
6.
7.
Jing Chen Yan Lin Jun Zhou Huo Ming Xia Zhang Zhuo Shang Ji 《Ocean Engineering》2010,37(11-12):978-988
Ship’s subdivision arrangement is a multi-objective combinatorial optimization problem with multiple nonlinear constraints. This study focuses on finding a methodology for ship’s subdivision arrangement that can guarantee ship’s offshore sequential ballast water exchanging (SBWE) performances in the preliminary design stage. A mathematical model is built using minimizing trims and hull girder longitudinal bending moments and shearing forces occurred in the SBWE as the objectives, and the multiple safety criteria of the SBWE as the constraints. The longitudinal lengths of the ballast water tanks (BWTs) are taken as design variables that will alter within a reasonable length range. An elitist nondominated sorting genetic algorithm (NSGA-II) is utilized to perform the optimization, in which the nondominated sorting mechanism is employed to handle the multiple objectives, and the constraint-domination principle is utilized to handle the multiple constraints. A special crossover operator called the dispersion apportioned allelic (DAA) crossover is introduced to perform the reproduction of the special problem. A real case study of the subdivision arrangement based on the SBWE of a 50,000DWT double hull product tanker is conducted to demonstrate the feasibility and effectiveness of the proposed approach. 相似文献
8.
海洋平台优化设计的研究进展 总被引：4，自引：0，他引：4
结构优化是结构设计理论的重要发展,随着“十五”渤海大油田勘探开发战略的实施,结构优化技术将在新型抗冰振平台设计中发挥重要作用。从静力优化设计、动力优化设计、基于可靠度优化设计、全寿命优化设计四个方面论述了海洋平台结构优化设计的研究现状,并展望了海洋平台优化设计的研究前景。 相似文献
9.
在金属氧化物阳极材料研究中，采用了均匀设计方法对阳极涂层成分进行优化设计，依据阳极电化学性能试验结果，建立了阳极性能与成分间的数学模型。在回归分析基础上，筛选出金属氧化物阳极涂层成分的最佳配方，并探讨了涂层成分对阳极性能的影响。试验结果表明，贵金属组元铂的加入对金属氧化物阳极的电化学性能影响并不明显；金属氧化物阳极的电化学性能主要受贵金属铱和惰性组元钽的影响。 相似文献
10.
船体支柱的布局影响到船舶功能性舱室的布置及相应的结构设计,而目前支柱布局多依赖母型船或者工程师设计经验,缺少基于数学优化的技术支撑。变密度的拓扑优化方法可将属于离散变量优化的支柱布局问题转化为连续变量优化问题。通过悬臂梁—支柱结构的算例,验证了该方法用于解决支柱布局优化问题的可行性。针对某型VLCC的支柱—大跨度甲板结构的支柱布局优化问题,根据布置限制条件设定了支柱优化设计域,选择了两种不同的优化目标函数进行支柱的布局优化设计,最后对优化结果进行了对比分析。结果表明,本方法具有较好的可行性,无需过多设计经验即可优化得到结构性能较好的支柱布局方案,可为此类的支柱布局优化设计提供技术支撑。 相似文献
11.
12.
工业产品设计方案的模糊综合评价方法 总被引：1，自引：0，他引：1
本文根据工业产品的特点，建立了工业产品设计方案评价指标体系──－多级多指标评价体系，且具有模糊的特点．通过引入模糊优选理论，提出了设计方案模糊综合评价方法，并将其应用于除湿机的设计方案评价和选优． 相似文献
13.
Design Curves for Mooring Lines of Turret Mooring Systems 总被引：1，自引：0，他引：1
Gao Jie Tan Jiahua Chen Xiaohong
Associate Professor Shanghai Jiao Tong University Shanghai
Professor Shanghai Jiao Tong University Shanghai
Lecturer Shanghai Jiao Tong University Shanghai 《中国海洋工程》1997,(4)
This paper presents a series of design curves to aid in the selection of turret mooring systemsfor tankers based Floating Production Storage and Offloading(FPSO)systems.These curves are appropri-ate to water depths ranging from 100m to 600m.The curves can be used as a preliminary design tool,al-lowing the designer to quickly evaluate alternative mooring system configurations,including the numberof mooring lines,the characteristics of chain and wire rope to be deployed and the initial tension.With aknowledge of the total environmental force and vessel motion characteristics,the designer can determinethe appropriate system for closer evaluation. 相似文献
14.
Combining high precision numerical analysis methods with optimization algorithms to make a systematic exploration of a design space has become an important topic in the modern design methods. During the design process of an underwater glider''s flying-wing structure, a surrogate model is introduced to decrease the computation time for a high precision analysis. By these means, the contradiction between precision and efficiency is solved effectively. Based on the parametric geometry modeling, mesh generation and computational fluid dynamics analysis, a surrogate model is constructed by adopting the design of experiment (DOE) theory to solve the multi-objects design optimization problem of the underwater glider. The procedure of a surrogate model construction is presented, and the Gaussian kernel function is specifically discussed. The Particle Swarm Optimization (PSO) algorithm is applied to hydrodynamic design optimization. The hydrodynamic performance of the optimized flying-wing structure underwater glider increases by 9.1%. 相似文献
15.
SONG Yupu FENG Sheng KANG Haigui
Professor Ph. D. PhD Supervisor State Key Laboratory of Coastal Offshore Engineering Dalian University of Technology 《中国海洋工程》1999,(3)
This paper proposes an optimum design medel for the offshore jacket platform considering multi-design criteria,multi-design constraints and the structure-pile-soil interaction,and gives an optimum designprocedure in which the proposed optimum design model is used together with structural analysis softwareSAP91 and optimum algorithm software OPBI.The Chengbei ~#11 offshore platform,which lies in theShengli oil field,is designed by use of the above optimum design model.The results show that the optimumdesign model is stable,and it depends on neither the optimization algorithm nor initial values of design vari-ables.All values of the objective function converge to the same minimum value,and the speed of conver-gence is high,showing that the proposed optimum design model is reasonable. 相似文献
16.
An optimization approach for fairing of ship hull forms 总被引：2，自引：0，他引：2
Ebru Sariz 《Ocean Engineering》2006,33(16):2105-2118
This paper presents a numerical fairing procedure to be used at the preliminary design stage to create high-quality ship hull form geometry. The procedure is based on a variational optimization approach in which a fairness measure related to the surface curvature is the objective function to be minimized subject to a set of geometric constraints to ensure that the final form has the required geometric characteristics. The optimization variables are selected as the control points of a B-spline surface representing the initial hull form. A nonlinear direct search technique is employed to solve the problem. The methodology is applied for typical ship forms to indicate that, provided that the designer can specify appropriate design objectives and geometric constraints, the methodology can produce alternative hull forms with significantly improved fairing characteristics. The choice of the fairness objective function is shown to have a crucial effect on the quality of the hull surface. Highly nonlinear exact fairness functionals yield surfaces of high quality at the expense of high-computerized effort. 相似文献
17.
The floating oil storage system has been proposed as a new facility for Strategic Petroleum Reserve (SPR) in China. Mooring is one of the key technologies to ensure the safety, reliability, and performance of the oil storage system. This paper describes the concept, analysis, design and reliability of the mooring system. For mooring system design of these oil vessels, analysis is essential of the behavior of the vessel in connection with mooring facilities of nonlinear resilience. A nonlinear mathematical model for analyzing a moored vessel is established and solved. Some results of numerical simulations are presented. Assessment of the safety regarding the mooring system in terms of failure probability is carried out. Another simulation model for calculating the failure probability of the mooring system is proposed. The design parameters that have an influence on the characteristics of the failure probability have been identified. The simulation results show that the mooring system has an annual reliab 相似文献
18.
A ship optimal trajectory planning method based on the dynamic model of the ship is presented. First a mathematical modular model is introduced for describing the non-linear dynamics of the ship. Then the problem of optimal trajectory planning is discussed. The trajectory is obtained through the optimization of a time-energy criterion, taking into account constraints on the steering system, environment, non-linearities, and non-convexity of the state space equations. The discrete augmented Lagrangian approach is used to compute the optimal constrained controller. The method was programmed on a HP700 workstation. This approach was applied to automatic ship berthing maneuver 相似文献
19.
水下柔性鱼形机构原理及单尾鳍板水动力试验研究 总被引：4，自引：0，他引：4
柔性鱼形机构是模拟鱼类运动的一种仿生机械系统。对鱼类运动的观察与研究 ,实质上是寻求水域中最优推进形式的过程 ,是工程优化设计的途径之一。在研究及优化柔性鱼形机构时涉及到水动力学及控制模型的问题 ,因此取出鱼形机构的尾鳍部分进行敞水试验 ,既能为有关模型的建立提供依据 ,更重要的是对鱼形机构的可行性进行论证 相似文献
20.
A semi-analytic approach is presented in this paper which is capable of predicting the static performance of marine cables. The solution is derived as a function of only three parameters which can be solved numerically by implementing different kinds of boundary conditions. The efficiency and accuracy of the method permit quick parametric studies for optimal selection of the system particulars which is undoubtedly useful for preliminary design. A number of numerical examples demonstrates the validity of the approach adopted. 相似文献