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China Ocean Engineering 2020年第4期34卷 488-499页

作者： YUAN Yu-chao XUE Hong-xiang tang wen-yong State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Vortex-induced vibration(VIV)for flexible cylinders under combined uniform and oscillatory flow is a challenging and practical issue in ocean *** this paper,a time domain numerical model is adopted to investigate the characteristics of cross-flow VIV response and fatigue damage under different combined flow ***,the adopted VIV model and fatigue analysis procedure are validated well against the published experimental results of a4-m cylinder model under pure oscillatory ***,forty-five combined flow cases of the same cylinder model are designed to reveal the VIV response characteristics with different non-dimensional oscillation period T^*and combined ratio *** combined flow cases are classified into three categories to investigate the effect of r on cylinder’s dynamic response,and the effect of T*is described under long and short period ***,fatigue analysis is carried out to investigate how the structural fatigue damage varies with the variations of r and T^*.The captured characteristics of structural response and fatigue damage are explained through the VIV mechanism analysis.

关键词： vortex-induced vibration fatigue damage flexible cylinders combined flow

Theoretical Approximation of Focusing-Wave Induced Load upon A Large-Scale Vertical Cylinder

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China Ocean Engineering 2017年第5期31卷 598-606页

作者： XUE Hong-xiang HU Zhe tang wen-yong ZHANG Xiao-ying WANG Kun-peng State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Key Laboratory of Ships and Ocean Engineering of Fujian Province Jimei University School of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology

Until now, most researches into the rogue-wave-structure interaction have relied on experimental measurement and numerical simulation. Owing to the complexity of the physical mechanism of rogue waves, theoretical study on the wave-structure issue still makes little progress. In this paper, the rogue wave flow around a vertical cylinder is analytically studied within the scope of the potential theory. The rogue wave is modeled by the Gauss envelope, which is one particular case of the well-known focusing theory. The formulae of the wave-induced horizontal force and bending moment are proposed. For the convenience of engineering application, the derived formulae are simplified appropriately, and verified against numerical results. In addition, the influence of wave parameters, such as the energy focusing degree and the wave focusing position, is thoroughly investigated.

关键词： rogue wave Gauss envelope upright cylinder potential theory analytical approximation

Behavior of Unbonded Flexible Risers Subject to Axial Tension

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China Ocean Engineering 2014年第2期28卷 249-258页

作者：任少飞唐文勇郭晋挺 State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Naval Architecture and Marine Engineering University of Michigan

Owing to nonlinear contact problems with slip and friction, a lot of limiting assumptions are made when developing analytical models to simulate the behavior of an unbonded flexible riser. Meanwhile, in order to avoid convergence problems and excessive calculating time associated with running the detailed finite element （FE） model of an unbonded flexible riser, interlocked carcass and zeta layers with complicated cross section shapes are replaced by simple geometrical shapes （e.g. hollow cylindrical shell） with equivalent orthotropic materials. But the simplified model does not imply the stresses equivalence of these two layers. To solve these problems, based on ABAQUS/Explicit, a numerical method that is suitable for the detailed FE model is proposed. In consideration of interaction among all component layers, the axial stiffness of an eight-layer unbonded flexible riser subjected to axial tension is predicted. Compared with analytical and experimental results, it is shown that the proposed numerical method not only has high accuracy but also can substantially reduce the calculating time. In addition, the impact of the lay angle of helical tendons on axial stiffness is discussed.

关键词： unbonded flexible risers axis stiffness quasi-static contact friction

Analytical and Numerical Models to Predict the Behavior of Unbonded Flexible Risers Under Torsion

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China Ocean Engineering 2016年第2期30卷 243-256页

作者：任少飞薛鸿祥唐文勇 State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240China

This paper presents analytical and numerical models to predict the behavior of unbonded flexible risers under *** analytical model takes local bending and torsion of tensile armor wires into consideration,and equilibrium equations of forces and displacements of layers are *** numerical model includes lay angle,cross-sectional profiles of carcass,pressure armor layer and contact between ***/Explicit quasi-static simulation and mass scaling are adopted to avoid convergence problem and excessive computation time caused by geometric and contact *** show that local bending and torsion of helical strips may have great influence on torsional stiffness,but stress related to bending and torsion is negligible;the presentation of anti-friction tapes may have great influence both on torsional stiffness and stress;hysteresis of torsion-twist relationship under cyclic loading is obtained by numerical model,which cannot be predicted by analytical model because of the ignorance of friction between layers.

关键词： unbonded flexible riser torsion tensile armor layers anti-friction tapes load distribution quasi-static

Cross-Flow VIV-Induced Fatigue Damage of Deepwater Steel Catenary Riser at Touch-Down Point

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China Ocean Engineering 2014年第1期28卷 81-93页

作者：王坤鹏唐文勇薛鸿祥 State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University

A prediction model of the deepwater steel catenary riser VIV is proposed based on the forced oscillation test data, taking into account the riser-seafloor interaction for the cross-flow VIV-induced fatigue damage at touch-down point （TDP）. The model will give more reasonable simulation of SCR response near TDP than the previous pinned truncation model. In the present model, the hysteretic riser-soil interaction model is simplified as the linear spring and damper to simulate the seafloor, and the damping is obtained according to the dissipative power during one periodic riser-soil interaction. In order to validate the model, the comparison with the field measurement and the results predicted by Shear 7 program of a full-scale steel catenary riser is carried out. The main induced modes, mode frequencies and response amplitude are in a good agreement. Furthermore, the parametric studies are carried out to broaden the understanding of the fatigue damage sensitivity to the upper end in-plane offset and seabed characteristics. In addition, the fatigue stress comparison at TDP between the truncation riser model and the present full riser model shows that the existence of touch-down zones is very important for the fatigue damage assessment of steel catenary riser at TDP.

关键词： VIV steel catenary riser touch-down point riser-soil interaction fatigue damage

Numerical Wave Tank Based on A Conserved Wave-Absorbing Method

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China Ocean Engineering 2016年第1期30卷 137-148页

作者：扈喆唐文勇薛鸿祥张晓莹 State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China Collaborative Innovation Center for Advanced Ship andDeep-Sea Exploration Shanghai 200240 China Bureau Veritas Marine (China) Co. Ltd Shanghai 200011 China

Recently the numerical wave tank has become a widely-used tool to study waves as well as wave-structure interactions, and the wave-absorbing method is very important as its effect on the quality of waves generated. The relaxation method and the derived momentum source method are often utilized, however, the damping weight is constant during calculation and repeated trials are required to obtain an acceptable wave-absorbing effect. To address the abovementioned issues, a conserved wave-absorbing method is developed. The damping weight is determined by solving the mass conservation equation of the absorbing region at every time step. Based on this method, a two-dimensional numerical wave tank is established by using the VB language to simulate various waves by which the validation of this method is evaluated.

关键词： conservation wave absorption weight numerical wave tank waves

基于波分析法油膜刚度对轴系扭转振动影响的研究（英文）

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船舶力学 2015年第9期19卷 1139-1148页

作者：杨勇车驰东唐文勇上海交通大学海洋工程国家重点实验室上海200030 中国船舶及海洋工程设计研究院上海200011

为确保带减速齿轮箱主推进系统的可靠性,文章对船舶轴系的扭转振动进行了研究。首先根据各组成部件的特点将轴系分解为连续和离散的两个子系统,分别利用波分析法和多自由度系统分析法列出连续子系统的波动形式及离散子系统的振动微分方... 详细信息

为确保带减速齿轮箱主推进系统的可靠性,文章对船舶轴系的扭转振动进行了研究。首先根据各组成部件的特点将轴系分解为连续和离散的两个子系统,分别利用波分析法和多自由度系统分析法列出连续子系统的波动形式及离散子系统的振动微分方程,同时考虑了减速齿轮箱油膜刚度的影响。然后根据两子系统连接处的动态平衡和连续条件,建立整个轴系在扭转振动模式下总运动方程,通过求解总方程得到系统的位移响应。该扭转振动分析被应用到某LNG船带减速齿轮箱的轴系振动计算中,通过考虑轴系减速齿轮箱啮合齿面间油膜刚度使轴系扭转振动模型更接近轴系实际运转工况。计算结果显示:随着减速齿轮箱啮合齿面间油膜刚度的增加,最大轴系扭转应力向低转速区域偏移。这对船舶轴系转速禁区的划分产生极大的影响。有助于防止因不良轴系振动计算引起轴系事故的发生。

关键词：轴系扭转振动波分析油膜刚度

计及弹性支撑效应的独立液舱晃荡数值分析研究

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船舶力学 2017年第1期21卷 23-30页

作者：刘文夫薛鸿祥唐文勇上海交通大学海洋工程国家重点实验室上海200240 高新船舶与深海开发装备协同创新中心上海200240

文章针对弹性支撑结构作用下的液舱晃荡问题,采用基于Hilber-Hughes-Taylor(HHT)格式的隐式直接积分法求解液舱运动,应用VOF法求解流体晃荡,并结合部分单元参数的概念处理棱形液舱边界,建立了液舱运动与流体晃荡双向耦合迭代算法。以独... 详细信息

文章针对弹性支撑结构作用下的液舱晃荡问题,采用基于Hilber-Hughes-Taylor(HHT)格式的隐式直接积分法求解液舱运动,应用VOF法求解流体晃荡,并结合部分单元参数的概念处理棱形液舱边界,建立了液舱运动与流体晃荡双向耦合迭代算法。以独立液舱为研究对象,通过耦合求解弹性支撑液舱晃荡,并与非弹性支撑液舱晃荡进行比较,分析了在不同刚度的弹性支撑结构作用下液舱液体运动及晃荡载荷的变化规律。该文建立的分析方法为含弹性支撑的独立液舱晃荡载荷预报提供了一种快速、有效的分析手段。

关键词：弹性支撑独立液舱液舱晃荡 VOF方法

水下生产系统跨接管结构在地震作用下动力响应分析

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振动与冲击 2013年第4期32卷 48-53页

作者：赖文龙唐文勇薛鸿祥上海交通大学海洋工程国家重点实验室上海200240

研究水下生产系统跨接管结构在地震波载荷下的动力响应特性。分析中计及了地震波沿水平和竖向两个方向的载荷输入,采用非线性弹簧模型模拟跨接管与海床的耦合作用,同时考虑了地震作用下跨接管的动水作用效应。通过对不同影响因素下结构... 详细信息

研究水下生产系统跨接管结构在地震波载荷下的动力响应特性。分析中计及了地震波沿水平和竖向两个方向的载荷输入,采用非线性弹簧模型模拟跨接管与海床的耦合作用,同时考虑了地震作用下跨接管的动水作用效应。通过对不同影响因素下结构的动力响应结果分析表明:竖向地震波对跨接管结构水平响应幅值影响较小,但显著改变其响应频率;管土接触引起跨接管响应幅值变化明显,并激发跨接管高阶振型;地震下动水作用力对跨接管的响应幅值影响较大。所建立的分析方法对跨接管结构设计和安全性评估有一定借鉴意义。

关键词：水下生产系统跨接管动力响应地震波非线性弹簧

基于绿色造船技术减振降噪措施在极地破冰科学考察船上的应用(英文)

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船舶力学 2014年第6期18卷 724-737页

作者：杨勇车驰东唐文勇上海交通大学海洋工程国家重点实验室上海200030

为确保船上主要设备和精密仪器在恶劣极地环境下正常工作,改善船员宜居性,根据复杂隔振系统特点,对某极地破冰科学考察船上主要振源采用各种减振降噪技术。通过对主柴油发电机组和停泊发电机组分别采用双层隔振系统和单层隔振系统,机舱... 详细信息

为确保船上主要设备和精密仪器在恶劣极地环境下正常工作,改善船员宜居性,根据复杂隔振系统特点,对某极地破冰科学考察船上主要振源采用各种减振降噪技术。通过对主柴油发电机组和停泊发电机组分别采用双层隔振系统和单层隔振系统,机舱泵组采用浮筏隔振系统进行减振处理。为提高船员宜居性,采用阻尼材料和特殊结构吸收舱室内噪声。通过采用上述措施,大大降低了相关舱室振动和噪声等级。因此,随着减振降噪等绿色造船技术的发展,必然改善和造福人类。

关键词：极地破冰科学考察船绿色造船宜居性减振降噪