Development of Marine Remote Sensing Technology in China

 

LIU Chang¹，BAI Qiang²，TANG Gao²，SHAO Hui²，BAI Yong^1,2

（1. Southern University of Science and Technology, Shenzhen 518000, China；

2. Shenzhen Zhongxin Intelligent Technology Co., Ltd., Shenzhen 518000, China）

 

Abstract: Remote sensing technologies used in obtaining marine environmental input data has contributed greatly to the development of naval architecture and ocean engineering. This paper introduces the status of remote sensing satellites and the ocean monitoring with satellites in China, including monitoring of sea surface temperature, ocean color, sea ice disaster, green tide disaster, red tide disaster, offshore oil spill, typhoons at sea and so on. At the same time, the future development of ocean remote sensing technology is discussed. The real-time ocean monitoring technology is going to be developed and the remote sensing information extraction and data application will be improved. Taking the advantages of Internet technology and cloud computation, the cloud-based ocean database network and big data platform can be established. Thus the ocean data sharing can be realized through big data collection, storage, computing and analysis.

Key words:satellite; ocean remote sensing; ocean monitoring; big data

 

 

 

Research Technique and Development of Coupled Dynamic

Performance of Offshore Floating Wind Turbines

 

WANG Han，HU Zhi-qiang

（State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai 200240, China）

 

Abstract: The coupled dynamic performance of the offshore floating wind turbine system is very complex, and the design of an offshore floating wind turbine is a typical example of system engineering that involves multidisciplinary optimization. This paper summarizes the technical researches and development related to the coupled dynamic performance of offshore wind turbines at home and abroad, and elaborates from the aspects of model development, numerical calculation program development, theoretical modelling, model testing, dynamic performance analysis and so on, in order to lay a foundation for deeper and more comprehensive studies in the future.

Key words:floating wind turbine; coupled dynamic performance; multidiscipline; aerodynamic loads; hydrodynamic performance; numerical calculation; model test

 

 

 

Development of Mooring Force Calculation Software Complying with OCIMF Guidelines

 

ZHAO Zhen-hua, WEI Tao, WANG Shu-biao, JIA Cheng-jun

（Jiangnan Shipyard (Group) Co., Ltd., Shanghai 201913, China）

 

Abstract: According to the mooring force calculation requirements of the latest edition of OCIMF Mooring Equipment Guideline, selection of mooring lines for liquefied gas carriers and tankers is no longer based on the quantity of outfitting, but complied with the results of Oil Companies International Marine Forum (OCIMF) mooring force calculation. The standard is increased a lot, and the calculation process becomes relatively complex and cumbersome. This paper evaluates the mooring forces with VB.Net programming language according to the latest edition of the OCIMF Guidelines. Computer software program is developed to save computing time, improve calculation accuracy, reduce human error, and carry out multi-scheme comparison to make the best choice. The study is of great significance to reduce the cost of shipbuilding and to improve work efficiency.

Key words:OCIMF; mooring force; programming; VB.Net

 

 

 

Stress Calculation of Semi-Hanging Rudder System Based

on Structural Finite Element Method

 

ZHENG Guan-chao，LIANG Xiao，HOU Yuan-hang

（Department of Marine Engineering, Tianjin Maritime Vocational College, Tianjin 300350, China）

 

Abstract: Asthere is no specific calculation scheme specified in the rules and regulations of classification societies for the force calculation of semi-spade rudder systems, the research institutions and scholars mainly focus their attentions on the simplified calculations models. While the exploration of relatively accurate numerical simulation method is only limited to the study of some simplified stocks or local parts. Aiming at this issue, this study establishes a full-scale model of the type 7 semi-hanging rudder in the regulation, and uses the structural finite element method to check its stress and structural strength. Meanwhile, in combination of the simplified calculation models proposed by various research institutions and scholars, a comprehensive evaluation and analysis is carried out to obtain their advantages and disadvantages, thus providing some suggestions and reference for the rudder system design and stress calculations.

Key words:semi-hanging rudder; structural finite element; stress calculation of rudder system; strength check

 

 

 

A Finite Element Analysis on the Structural Strength of

Type-C Independent Triple Cylinder Tank

 

GUO Yuan-yuan^1,2, TANG Wen-yong^1,2，ZHOU Bing³, ZHANG Ren-jie³

(1. State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;

2. Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240, China;

3. Shanghai Cryolobe Gas Technology Co., Ltd., Shanghai 200441, China)

 

Abstract: According to the requirements of International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC CODE), a global finite element analysis on the structural strength of type-C independent triple cylinder tank of a LNG (Liquefied Natural Gas) carrier is carried out with ABAQUS software. This paper introduces the model range, load conditions，boundary conditions and contact types, and refines the mesh of local high stress regions. Middle surface stress and surface stress of the liquid tank structure are checked. The paper also elaborates the stress characteristics of the triple cylinder tank based on the result of analysis, and proposes suggestions for improvement, which provides references to tank structure optimization.

Key words:type-C independent triple cylinder tank; IGC CODE; strength analysis

 

 

 

Design Features and Key Technologies of Ropax Ship

for Sino-South Korea Route

 

SUN Jia-peng, ZHANG Min-jian

（Shanghai Merchant Ship Design & Research Institute, Shanghai 201203, China）

 

Abstract: Based on the accidents frequently occurred to passenger ships in recent years and the more stringent rules and regulations leading to ropax ships updates for Sino-South Korea routes, this paper introduces in detail the design features and key technologies of the new generation ropax ships for the Sino-South Korea route with regard to the characteristics of ro-ro cargoes, high efficiency cargo handling, passenger cabin and public recreation areas, hull lines design optimization, passenger comfort and environmental aspects. Meanwhile, objective comments on the status quo of Sino-South Korea trade are made along with outlooks.

Key words:ropax; Sino-South Korea route; high efficiency handling; hull line optimization; passenger comfort

 

 

 

Contact Load Calculation Method for the Support Structure of

Type-C Independent Liquid Tank

 

QIN Bin, ZHOU Qing-hua, LI Xiao-ling

（Jiangnan Shipyard (Group) Co., Ltd., Shanghai 201913, China）

 

Abstract: In order to accurately check and analyze the load transfer and stress distribution in the region of the support structures of Type-C independent liquid tank on liquefied gas carriers, this paper uses the nonlinear contact analysis method to study the support regions according to the requirement of the latest edition of International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk and the rules of classification societies. A 37500m³ ethane carrier is taken as the object when the liquid tank finite element model is established to perform nonlinear contact analysis of the support regions. Then the method is compared with the static analysis method which is based on truss elements to obtain stress characteristics of Type-C independent tank and the laminated wood. The calculation result shows that the nonlinear contact analysis method is more accurate.

Key words:Type-C independent liquid tank; support structure; nonlinear; contact analysis

 

 

 

A Study on the Deadweight Design Method of

Very Large Container Vessels

 

DENG Kai¹，YUAN Hong-liang²，YAN Hui-min²

（1. School of Naval Architecture, Ocean & Civil Engineering, Shanghai Jiao Tong University, Shanghai 200030, China;

2. Hudong-Zhonghua Shipbuilding (Group) Co., Ltd., Shanghai 200129, China）

 

Abstract: The design of very large container ships has experienced a number of changes, from high speed to slow steaming, from narrow body to wide body, and from low deadweight tonnage to high carrying capacity. This study carried out data analysis on some very large container vessels to obtain the suitable design and evaluation method for the ship type. It provides references for the speedy and perspective design of very large container ships.

Key words: very large container vessel; deadweight tonnage; principal particulars; regression formula; energy efficiency index

 

 

 

Fatigue Analysis on the Lazy-Wave Flexible Riser

in Catenary Anchor Leg Mooring System

 

FU Tu-nan¹，HUANG Wei-ping¹，CAO Shu-gang²，CHANG Shuang¹

（1. Shandong Key Laboratory of Ocean Engineering, Ocean University of China, Qingdao 266100, China；

2. Zhong Neng Electric Power Technology Development Co., Ltd., Beijing 100034, China）

 

Abstract: Applying the unbondedflexible riser to the catenary anchor leg mooring system, a coupled numerical analysis model for the catenary anchor leg mooring system is established by means of ORCAFLEX software. The ABAQUS software is then used to study the stress distribution of different layers of the flexible riser under tension forces and bending moments, to obtain the stress coefficients of the inner and the outer tensile armor layers, and to further perform the fatigue analysis of the riser due to waves and vortex induced vibrations. The result shows that the fatigue life of the flexible riser in the system is mainly dependent on the inner tensile armor layer, with the maximum fatigue damage occurring near the connection point between the bend limit joint and the riser, and the tension influencing factors plays a more important role on the fatigue damage of this point than the curvature influencing factors.

Key words:lazy-wave; flexible riser; ORCAFLEX; fatigue life

 

 

 

Sediment Control Design for VLCC

 

WU Zhao-yang¹，CHAO Qing²，LIU Gang¹

（1. Marine Design & Research Institute, Shanghai Waigaoqiao Shipbuilding Co., Ltd., Shanghai 200137, China;

2. Lloyd¢s Register of Shipping, Shanghai 200001, China）

 

Abstract: Water containing mud will enter the ballast tank when VLCC (Very Large Crude Carrier) unloads in the port surrounded by muddy water. The mud sediments often deposit in the ballast tanks where there are many stiffeners, causing trouble to subsequent cleanings. To solve the problem, this study carries out simulations on the sediment deposition process for the VLCC sediment control design. It helps quantitative calculation of the sediment control effect of the sediment tanks, providing more technical reference for the future design and construction.

Key words:anti-mud; sediment tank; simulation

 

 

 

Modeling and Simulation of Hybrid Power Yacht

 

ZHENG Xiao

（Merchant Marine College, Shanghai Maritime University, Shanghai 201306, China）

 

Abstract: Compared with diesel generator powered ships, hybrid power yacht has the advantages of low fuel consumption, less pollution and low noise. Therefore, a hybrid power system with parallel connected battery-diesel engine sets is designed for the small yachts built in China. This paper introduces in detail the structure and component modeling of this hybrid power system, as well as its simulations on a 26.5m long, 6.2m wide yacht that has a maximum speed of 32 knots. Compared with diesel engine powered yachts, the yacht with parallel hybrid power system can not only save energy and reduce emission but also maintain the SOC of battery within a reasonable range.

Key words:hybrid power; yacht; modeling; simulation

 

 

 

Coordination Analysis for Electric Propulsion Ships

 

 LI Zhi-juan

（Marine Design & Research Institute of China, Shanghai 200011, China）

 

Abstract: Coordinated protection plays an important role in the safe and reliable operation of the flexible power system onboard electric propulsion ships. Taking the electric power system of an electric propulsion ship as the example, this paper puts forward a coordinated protection scheme based on the calculations and analysis, which provides reference for the design of marine electric propulsion system.

Key words:electric propulsion; coordinated protection; short circuit current

 

 

 

Precision Control Technique for Fitting of Container ISO Foundation Onboard Container Ships

 

GONG Zhao-ming, DONG Lian-bin, JIANG Jing, SONG Xue-hui

（DSIC Dalian Shipbuilding Co., Ltd., Dalian 116000, China）

 

Abstract: The limit installation tolerance for the flush iso foundation is derived through the study on the container loading precision requirements for containerships. To guarantee precision, the installation of the container flush iso foundation is shifted ahead to the section construction stage instead of the conventional procedure after hull closure. As the section construction method and the block closure form are optimized, the loading precision of the containers can be realized when hull construction is accomplished. Full-scale trial proved that the container flush iso foundation installation moves ahead can not only reduce the paint damage during block closure and the subsequent work of paint repair, but also shorten the berth (dock) cycle, and thus increasing the benefits of shipyards.

Key words:flush iso foundation; precision control; anti-deformation

 

 

 

Technical Measures Adopted to Reduce Pipe Welding

in Cargo Handling System

 

LIU Ming-ming，ZHANG Cheng-you

（Jiangnan Shipyard (Group) Co., Ltd., Shanghai 201913, China）

 

Abstract: The complexity of the cargo handling system leads to a large quantity of stainless pipes onboard and the wielding of these pipes may cause work delay, cost increase, unsatisfied installation quality and environmental pollution, etc. In order to solve the problem, this study seeks the solution from the source of the problem. Technical measures such as large unit hoisting, indoor pre-assembly and integrated hoisting are adopted to reduce stainless steel weld seam onboard, and thus to reach the goal of shortening ship construction period and environmental protection.

Key words:amount of weld seam; large unit hoisting; indoor pre-assembly; integrated hoisting