基于快速成型技术的抛弃式探头模型设计

抛弃式探头下沉数学模型的有效性及其运动的CFD仿真计算方法,都需要在较短时间内设计并制作模型实物,以进行实验验证。利用计算机辅助设计结合三维快速成型技术制作了探头模型,并在实验室水箱环境下进行了模型实验。探头模型的质量调整精确度较高,变化范围小于0.6 g,且重量分布均匀,下沉运动方向平稳;可控制其在有效实验水深内达到需要的下沉速度,利用高速摄像和图像处理后得到的实验结果准确可靠,可作为提高CFD仿真计算方法准确性的依据。     

基于Zemax外海观测光纤探针传感器探头结构的优化设计

光纤探针法是一种适合观测波浪破碎瞬间卷入微气泡羽流的方法,现有的观测探针探头多采用塑料、玻璃等材质,存在脆性大、损耗大、不耐低温、易腐蚀等缺点,拟设计一种蓝宝石光纤探针克服其局限性,提升探测性能.文章在介绍光纤探针传感器测量原理的基础上,采用光学仿真软件Zemax建立了光纤探针传感器探头的仿真模型,并利用模型对其每针的材质、形状、角度等结构设计关键因素进行了优化设计,由仿真结果确定了每针形状为圆锥形、传输材质为蓝宝石.该仿真结果将为后续光纤探针传感器系统的整体设计及光路优化奠定基础.     

基于Zemax的外海观测光纤探针传感器探头结构的优化设计

光纤探针法是一种适合观测波浪破碎瞬间卷入微气泡羽流的方法,现有的观测探针探头多采用塑料、玻璃等材质,存在脆性大、损耗大、不耐低温、易腐蚀等缺点,拟设计一种蓝宝石光纤探针克服其局限性,提升探测性能。文章在介绍光纤探针传感器测量原理的基础上,采用光学仿真软件Zemax建立了光纤探针传感器探头的仿真模型,并利用模型对其每针的材质、形状、角度等结构设计关键因素进行了优化设计,由仿真结果确定了每针形状为圆锥形、传输材质为蓝宝石。该仿真结果将为后续光纤探针传感器系统的整体设计及光路优化奠定基础。     

抛弃式探头下沉运动数值计算的网格划分方法研究

各类抛弃式探头下沉运动的数值计算研究都需要对探头表面和整个计算域进行网格划分的前处理过程,选择不同的网格划分方法和划分精度,会影响数值计算速度和计算精度,最终生成的网格质量决定了计算结果的收敛性和准确性。针对抛弃式探头的复杂结构,对比了两种网格划分方法、三种网格划分精度,完成探头计算区域的网格划分,采用k-ε湍流模型,进行抛弃式探头下沉运动的数值计算,并将计算结果与水箱和水库实验结果进行对比,验证了混合网格划分方法和普通精度网格对抛弃式探头下沉运动数值计算的适用性,研究结果对类似较为复杂结构的水下运动体的数值计算前处理过程具有一定的参考和借鉴意义。     

热毯式海底热流原位探测系统设计

针对海底热流探针无法对基岩海底或其他硬质海底进行热流探测的难题,基于傅里叶热力学第一定律提出了非插入式海底热毯原位探测方法,介绍了热毯式热流原位探测系统的设计。通过试验选择了合适的热毯盖层材料、对热毯的形状和设计尺寸等参数进行了设计优化,分析了热毯的工作方式并对布放技术进行了评价。热毯式海底热流探测系统为大洋中脊区域海底的热流探测提供了有效的方法,对于研究板块的热状态及板块的构造活动提供了广阔的应用前景。     

6000m级探测型AUV优化设计与阻力分析

使用ISIGHT集成EXCEL,ICEM,ANSYS FLUENT软件,搭建封闭耦合优化仿真平台。根据任务需求和布置需要得到设计变量、状态变量和目标函数,采用多岛遗传算法,优化求解得到局部最优AUV设计结果。借助SOLIDWORKS设计得到全附体模型,使用ANSYS CFX分别在0°,±2°,±4°,±8°,±16°攻角的条件下,计算其阻力值,经过经验公式对摩擦阻力的计算结果进行理论验证,证明了计算结果的可靠性。为6 000 m级探测型AUV的总体方案设计提供了线型参考和布局依据。     

基于遗传算法的潮流能水轮机叶片翼型优化设计研究

为了得到高性能的潮流能水轮机叶片翼型,本文在分析潮流能水轮机叶片翼型设计方法和设计要求的基础上,以NACA4418翼型为初始翼型,采用儒可夫斯基保角变换的方法对翼型进行参数化建模,以最大升阻比为目标函数,通过设定设计变量、施加约束条件等对初始翼型进行优化设计,采用MATLAB软件编程遗传算法进行全局寻优求解,寻找到最优解后,采用CFD(Computational Fluid Dynamic)软件Fluent对NACA4418翼型和优化翼型进行翼型绕流数值计算,比较数值计算结果表明,优化翼型相比于初始翼型升力系数和升阻比都有所提高。     

考虑结构-桩-土相互作用的导管架平台优化设计

首先建立了多设计准则、多约束条件的面向结构-桩-土相互作用的导管架海洋平台优化设计模型,然后给出了此模型与结构分析软件及优化算法软件相结合进行优化设计的方法,并以胜利油田埕北11#井单井采油平台为例进行优化设计.结果显示所建模型既不依赖于优化算法,也不依赖于初始设计值,目标函数值均收敛于同一极小值且收敛速度较快、减小幅度可观,从而说明了此模型的合理性.     

MPI环境下基于边界校正方法的海洋模型的并行化

基于区域分解技术,设计了一种针对海洋模型的边界校正方法,该方法不需要对原有海洋模型进行较大改动,只需要利用消息传递接口(message passing interface,MPI)编写子区域间的数据传输模块,即可实现原有海洋模型的并行化。相对于重新开发并行系统,该方法能够较快把原有模型的串行解决方案转化为并行解决方案,并且并行化后的海洋模型能够获得较高的加速比。     

UCTD探头阻力系数的数值分析及试验研究

为优化海洋动力参量拖曳式剖面测量系统(Underway Conductivity-Temperature-Depth instrument,UCTD)探头下降速度与稳定性,达到设计测量深度,提高观测数据质量,本文利用外型曲线解析式和探头基本运动方程完成初步设计,通过Fluent软件建立UCTD探头的流体动力学分析模型,计算相应的阻力系数,对其进行结构优化和重量调整,以满足技术指标的要求。2017年春季航次海试数据验证了数值仿真计算与探头结构设计的科学性和合理性,研究结果为UCTD探头水下运动规律研究和探头的设计提供参考。作为走航温盐剖面测量装置,UCTD可以快速、低成本地获取海洋水文剖面资料,广泛应用于海洋环境监测、海洋科学研究以及军事领域。     

水下升降式准实时通信潜标控制系统研制

为实现长期、连续、定点、低成本的上层海洋垂直剖面要素的准实时观测,提出了一种以STM32单片机(microcontroller unit,MCU)为主控器、采用国产温盐深传感器(conductivity temperature depth,CTD)和声学多普勒剖面流速仪(acoustic doppler current profilers,ADCP)等仪器进行剖面观测、搭载铱星通信模块或其他通信设备、适用于近海和远海的低功耗水下升降式准实时通信潜标控制系统设计方案。介绍了潜标的结构组成、控制系统硬件和软件设计,以及服务器接收软件的设计;实现了基于无线双向通信的数据补发机制和对潜标的远程控制;提出了一种适用于霍尔无刷直流电机(hall brushless direct current motor,HBLDCM)的堵转保护方法。近海和远海试验表明,该型潜标可以实现海洋垂直剖面的连续观测和数据的准实时传输,验证了潜标控制系统设计方案的可行性与稳定性。     

一种提高深远海全深度声速剖面重构精度的方法

开展多波束水深测量应同步进行声速剖面探测。因海上作业条件恶劣、作业时间受限及设备性能局限等影响,在深远海海域常获取不到全深度的实测声速剖面。尽管利用温盐场模型可将声速剖面直接延拓至实地水深的最大深度,但这种气候态平均声速剖面与实际的声速剖面间存在不可控的系统性偏差,会给声速改正及水深测量成果带来质量隐患。给出了一种提高深远海全深度声速剖面重构精度的方法,即利用有效探测深度附近的实测温度盐度值,对大于有效探测深度的各水层的模型温度盐度值施加程度不一的约束控制。结果表明,经优化后全深度声速剖面的重构精度得到明显提高,其中2个XCTD站点声速剖面的互差SSPD分别由-2.5～1.0 m/s优化为0.0～1.0 m/s、0.0～2.6 m/s优化为-1.5～0.0 m/s; 2个CTD站点声速剖面的互差SSPD分别由-0.5～1.7 m/s优化为-0.4～0.3 m/s、-2.15～0.8 m/s优化为-1.4～0.8 m/s。     

Simultaneous optimization of propeller–hull systems to minimize lifetime fuel consumption

In traditional naval architecture design methodologies optimization of the hull and propeller are done in two separate phases. This sequential approach can lead to designs that have sub-optimal fuel consumption and, thus, higher operational costs. This work presents a method to optimize the propeller–hull system simultaneously in order to design a vessel to have minimal fuel consumption. The optimization uses a probabilistic mission profile, propeller–hull interaction, and engine information to determine the coupled system with minimum fuel cost over its operational life. The design approach is tested on a KCS SIMMAN container ship using B-series propeller data and is shown to reduce fuel consumption compared to an optimized traditional design approach.     

Parametric Geometric Model and Hydrodynamic Shape Optimization of A Flying-Wing Structure Underwater Glider

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%.     

基于拓扑优化与多目标优化的集装箱相似畸变模型设计

使用相似原理构建缩尺模型是探究大型结构性能的最基本和最优途径。基于PATRAN软件的PCL语言与ISIGHT软件,提出一种联合静动力学、拓扑优化与多目标优化的集装箱相似畸变模型构建方法。利用拓扑优化的SIMP法(Solid Isotropic Material with Penalization)得到缩尺集装箱墙壁结构的最优材料分布,既保证了结构性能又降低了缩尺模型的重量;基于全局多目标算法建立优化模型,采用有限元方法对集装箱性能进行分析,以结构刚度和一阶模态频率为目标函数进行寻优,得到相似模型的最优设计参数。最终利用有限元分析验证该模型的合理性。结果表明:该方法具有一定的通用性,能为其它类似结构的相似模型构建提供参考。     

Optimum Design of Jacket Platforms Considering Structure-Pile-Soil Interaction

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.     

Optimization design on the riser system of next generation subsea production system with the assistance of DOE and surrogate model techniques

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.     

A decision support system for floating platform design

This paper describes a methodology developed for the preliminary design of floating production platforms. The preliminary design approach interlinks the mathematical design model with global optimization techniques. To illustrate the design procedure, the initial intermediate and final results are presented. They provide a clear understanding of the mathematical model and the decision support system. The preliminary design approach described here is based on the commercial software which is interfaced to what is called the FPS system and linked to a SEARCH package for design solutions. The paper summarizes the preliminary design approach, the mathematical model optimization and presents semisubmersible and TLP platform examples.     

南海北部海洋生态模型的参数分析及遗传算法优化

海洋生态系统动力学模型是研究海洋生态环境的重要手段。随着模型的发展, 生态参数取值不确定性增加, 对模型结果的影响逐渐增大, 因此模型参数优化显得尤为重要。本研究在南海北部应用一维物理-生态耦合模型, 通过对模型生态参数进行敏感性分析, 获取关键生态参数, 利用遗传算法对参数进行优化。结果表明, 模型中的敏感参数主要集中于浮游植物生长和浮游动物生长、摄食和死亡以及碎屑沉降等过程。针对以上参数利用遗传算法优化, 发现仅加入表层卫星数据, 模型表层和垂向模拟误差分别降低27.80%和21.40%; 加入垂向观测数据, 表层和垂向模拟误差分别降低14.90%和32.70%。遗传算法应用于海洋生态模型的关键参数优化研究, 所获取的参数对模型有明显的改善效果, 提高了耦合模型对生态系统的模拟精度, 为参数优化在三维模型中的应用提供了依据。