【作者】 刘建浩；

【导师】 杨启；

【作者基本信息】 上海交通大学 ， 船舶与海洋结构物设计制造， 2012， 硕士

【摘要】 随着人类社会科学技术的不断发展,全世界对各种金属矿产的需求量日益增大,其中锰、钴等矿产的需求量更是快速增长。然而,陆地矿产资源的储量十分有限,仅能满足人类在未来几十年的有限时间内的需求,且矿产开采成本随着密度下降而升高,因此寻求新的矿产来源是迫在眉睫的。在人类尚未进行开发的大洋深处,却蕴藏着丰富的金属矿产资源,其中锰结核与钴结壳是非常引人瞩目的,这两种资源中富含锰、钴、铜、镍等各种金属元素,其成分百分比与总储量都比陆地要大几个数量级。深海矿产可以在相当长的时期内满足人类的需求,因此,深海采矿成为多国的重点研究方向。本文从深海采矿的发展入手,介绍了国际上以提升方式划分的几种开采方案,并选取集矿车和水力提升相结合的采矿系统为研究对象,从采集、提升、水面母船三个子系统进行了较为详细的功能分析与研究。对采集系统做了主要功能的分析,对提升系统的尺寸、布置、连接方式以及材料做了较详细的设计,并根据对水面母船的功能分析,提出了采矿船的总布置方案。以此为基础,根据势波理论与六自由度的动力学平衡方程,利用挪威船级社的HydroD软件,在频域内对工作母船在波浪上的运动性能进行了预报,其中的升沉响应传递函数可为升沉补偿系统的设计提供参考。鉴于深海采矿提升管下端为悬垂状态,这与普通海洋平台立管有很大不同,因此其运动响应情况应予以关注,文章后续内容便锁定在对提升系统的运动响应分析上。本文选用通用有限元软件Abaqus,根据莫里森方程与五阶斯托克斯波理论,以及提升管的动力方程,对提升系统作了有限元建模计算与分析,主要从以下两方面入手:1.采矿作业中的不同工况提升管在水中受到海流、海浪的作用而发生形变,现实中主要关注管末中间仓的水平偏移、以及管道强度相关的弯矩、最大轴向应力等情况。本文对提升管在定点作业状态下、不同速度的母船移位状态下以及布放时的响应做了建模计算,得到了在这些情况下上述主要响应变量的值,并总结了由环境载荷的变化和约束方式不同所带来的响应变化规律,整理了一些结论,并综合以上计算的结果,对提升管材料进行校核,提出了最优方案。2.提升系统设计参数的影响在这一部分内容中,假设提升管的尺寸不变,以中间仓的重量、浮体所提供的浮力以及球铰接的应用为变量,模拟了提升系统在以上变量影响下的响应情况,总结了各因素的影响规律,并提出了球铰接的针对性设置方法。该部分工作中所得结论对于提升系的参数设计是具有一定的参考意义的。总体说来,本文较综合、系统地对水力提升式深海采矿系统进行了设计、模拟与分析,主要研究内容可以为深海采矿系统的设计、升沉补偿系统的研究以及实际的深海采矿作业提供有益参考。更多还原

【Abstract】 As the development of human’s science& technology, the world’s demand of various kinds of metals, especially manganese and cobalt , are increasing day by day. However, the mineral reserve in the land is very limited, which is only able to meet human’s requirement within a few decades now. And what’s more, the cost for mining is increasing with the decline of the mineral’s density. To sum up, it is urgent to look for new mineral resources. Deep in the bottom of the ocean, where we human haven’t developed yet, there are enormous scale of minerals, including manganese nodule and cobalt crust, which attract the attention from all around the world. The two kinds of minerals have a plentiful store of manganese, cobalt, copper, nickel and other kinds of metallic elements, both the percentage and total storage of which are both several orders of magnitude of that in the land. The minerals deep in the ocean are able to meet human requirement in a quite long period. Therefore, deep-sea mining becomes a focal point of study for many countries in the world.This thesis begins with the development of deep-sea mining, a few mining programs classified by hoisting styles are introduced, then a mining system of combined mining vehicle and hydraulic hoisting is chosen and introduced in detail as well as studied from three sub-systems, which are collecting system, hoisting system and mother ship system. Function analysis is made for the collecting system. A relatively detailed design regarding size, arrangement, joint method and material is made for the hoisting system. Based on function analysis of the mother ship, the RAOs of the ship are calculated according to potential wave theory and dynamic equilibrium equation of six degree of freedom through HydroD software from Det Norske Veritas, and frequency-domain motion performance of the ship is therefore predicted briefly, of which the heave RAO provides reference for heave compensation system design.The significant difference of deep-sea mining hoisting pipe from common ocean platform pipes is that the lower end is free, which makes its motion response notable. So the rest part of the thesis focuses on the motion response of the hoisting system. Based on Morison equation, 5-order Stokes wave theory and dynamic equation of the hoisting pipe, a general-purpose finite element software Abaqus is chosen to simulate the system. This part is divided into mainly two aspects as follow.1. Different Working Condition During Mining OperationAs the impact of ocean current and waves, the riser is deformed. The most important parameters we care about are the horizontal offset of the mid-bin, maximum moment and axial stress, etc. The riser in different conditions such as working in a fixed position, mother ship shifting and installation progress are simulated, the parameters mentioned above are gained, as well as some conclusions regarding parameters’variation due to the change of environmental loads and restrains. And the material of the riser is checked through the calculations mentioned, thereby an optimal choice is made .2. Impact of The Design Parameters of The Hoisting SystemIn this part, the size of the hoisting pipe is assumed to be fixed. The variables are chosen to be the weight of the mid-bin, the installation of buoyancy bodies and the appliance of spherical joints. The influence of which to the response parameters of the hoisting pipe is simulated, the influence disciplines of the variables are summarized, and a method of using ball joint properly is proposed. The conclusions of this part is of reference value to the hoisting system design.To sum up, a relatively comprehensive study of the deep-sea mining system is made in this paper, including design, simulation and analysis. The main research contents can provide useful reference for the design of deep-sea mining system, the study of heave compensation system and actual deep-sea mining operations.更多还原