Floating Production Platforms and their Applications in the Development of Oil and Gas Fields in the South China Sea

This paper studies the current available options for floating production platforms in developing deepwater oil fields and the potential development models of future oil and gas exploration in the South China Sea. A detailed review of current deepwater platforms worldwide was performed through the examples of industry projects, and the pros and cons of each platform are discussed. Four types of platforms are currently used for the deepwater development: tension leg platform, Spar, semi-submersible platform, and the floating production system offloading. Among these, the TLP and Spar can be used for dry tree applications, and have gained popularity in recent years. The dry tree application enables the extension of the drilling application for fixed platforms into floating systems, and greatly reduces the cost and complexity of the subsea operation. Newly built wet tree semi-submersible production platforms for ultra deepwater are also getting their application, mainly due to the much needed payload for deepwater making the conversion of the old drilling semi-submersible platforms impossible. These platforms have been used in different fields around the world for different environments; each has its own advantages and disadvantages. There are many challenges with the successful use of these floating platforms. A lot of lessons have been learned and extensive experience accumulated through the many project applications. Key technologies are being reviewed for the successful use of floating platforms for field development, and potential future development needs are being discussed. Some of the technologies and experience of platform applications can be well used for the development of the South China Sea oil and gas field.

Application of Tension Leg Platform Combined with Other Systemsin the Development of China Deepwater Oil Fields

The development of deepwater oil fields has reached a new stage with the dramatic increase in water depth and the recent increasing demands of the economic development in the filed. The use of a Tension Leg Platform （TIP） combined with other systems, such as Floating Production Storage and Offloading （FPSO） system, Floating Production Unit （FPU） system, Tender Assisted Drilling （TAD） system, etc., has drawn the industry attention and increased significantly in the past few years. For the areas lacking of pipeline system, the use of TIP（s） combined with FPSO has been chosen to efficiently develop the deepwater fields. The TIP with a Tender Assisted Drilling system significantly reduces the payload of the platform and reduces the investment in the TIP system substantially. This opens the door for many new deepwater field developments to use the tension leg platform. The advantage of the TIP combined with a TAD system is more significant when several TIPs are used for the continuous development of the field. One of the applications for the TIP with a tender assisted drilling system can be in the development of an offshore marginal field. Owing to the increase of water depth, the conventional fixed platform model for the exploration of those fields becomes uneconomical. It also would be too expensive to use a large TIP structure for those marginal fields due to the large amount of initial investment. The TIP system with tender assisted drilling can be used to develop those fields economically. There are many marginal fields in China offshore, especially in shelf areas. The application of this field developing model, combined with the existing field developing experience in China, will open the door for many marginal field developments. This paper will review the application of the combined TIP system through some examples of completed/ongoing projects, and major technical issues encountered in those practices. The potential application of this technology in China deepwater development will be discussed in the end.

Numerical Prediction and Field Verification Test of Wind-Power Generation Potential in Nearshore Area Using a Moored Floating Platform

The offshore turbine system was installed on a floating platform moored in Hakata Bay, offshore of Fukuoka, Japan. An identical turbine system was also installed at the adjacent waterfront. The separation of the two turbines was 3.7 km. Wind flow tends to be more stable and the average wind speed is often larger in offshore areas than adjacent land areas at typical wind turbine hub height. This study focused on the wind condition of a nearshore area to clarify the advantages of nearshore wind farming. Prior to field experiment, wind conditions were predicted by using numerical simulation. It is useful for estimating topographical effect in nearshore areas. Next, field verification test was done by directly comparing wind data obtained from the identical wind turbine systems installed at an offshore location and the adjacent waterfront over the same extended period. The corresponding power output of these turbines was also compared. The data set exhibits 23% larger annual average wind speed at the offshore location and smaller turbulent intensity, resulting doubled annual power production.

Advanced Platform Techniques for Chinese Offshore Marginal Oil Fields

Chinese offshore oil exploration and development have been carried out for more than 40 years. Until the end of 2000, the number of oil and gas fields under exploration grew up to 24. Though the reserves under exploration reached 608 Mt, it is only a part less than 50% of all the proved geological reserves. A majority of those untouched offshore oil and gas fields are marginal oil field, and there would be a momentous loss for Chinese energy industry if they were still left there unemployed. In recent years, based on the practical experience and rational research, lots of innovative techniques have been introduced into Chinese offshore oil fields to reduce the exploration cost. The author reviewed the development process of exploration in Chinese offshore marginal oil field. Several valuable techniques for advanced platform in offshore marginal oil field are also reviewed.

Vibration Characteristics of An Offshore Platform and Its Vibration Control

A template offshore platform, located in the Bohai Bay of China, has exhibited excessive, unexpected vibration under mildly hostile sea conditions, which has affected the normal operation of the platform. Since the structure was designed to sustain more severe wave climate, the cause of the excessive vibration has been suspected to originate from other sources. The main objectives of this study are to investigate the causes of the excessive vibration, and to explore possible remedies to solve the problem. In this paper, the vibration behavior of the offshore platform is analyzed by means of finite element (FE) modeling, field measurements and laboratory test. Results of analysis suggest that relative movement and impact between the piles and the jacket legs exist, i.e. the piles and the jacket are not perfectly connected. The disconnection of the piles and jacket weakens the overall stiffness of the platform, and therefore produces unexpected excessive vibration. In this study, measures for reducing the excessive vibration are proposed to control the response of the platform.

Next Frontier in Physics—Space as a Complex Tension Field

We hypothesize that 100% of the energy of our cosmic system is held by a physically real Complex Tension Field (CTF). We are using an old methodology of thinking used by our forefather engineers long before the advent of modern scientific thinking. We call it Interaction Process Mapping Epistemology or IPM-E. We apply this IPM-E on to the prevailing Measurable Data Modeling Epistemology or MDM-E. This approach helped us analyze the “Measurement Problem”, recognized during the rise of quantum mechanics (QM), and helped us recover a universal property of all linear waves, that they do not interact, or interfere, with each other. This Non-Interaction of Waves, or the NIW-property, should be obvious through daily observations and through the Huygens-Fresnel diffraction integral and through critical evaluation of contradictory hypotheses we have been assigning to photons through ages. This implicates that the time-frequency Fourier theorem, although mathematically correct, and is used universally in all branches of science;does not map the real physical interaction processes for most optical phenomena. Accordingly, we present the necessary modifications for a few selected phenomena in classical and quantum optics to validate the NIW-property. In the process we find that accepting photons as non-interacting, but diffractively propagating linear wave packets crossing the entire cosmic space, requires CTF as a physical medium. Then we develop logical arguments in support of stable elementary particles as nonlinear but resonant vortex-like undulations of this same CTF. These vortex-like particles impose various secondary potential gradients around themselves giving rise to the four forces we know. Thus, CTF can serve as the cosmic substrate to develop a unified field theory without the need of dark matter and dark energy. In the process, we demonstrate a path to add ontologic thinking on our biologically successful epistemic thinking.

数字平台场域互动观的建构研究

文章依据社会学中的场域理论,提出“数字平台场域互动观”。研究发现,数字平台具有“场域”属性,是一种商业场域,场域理论在此具有独到的解释力;互动在数字平台中扮演核心角色,是数字平台运行的微观基础;数字平台的场域互动模式包括同场域互动模式、跨场域互动模式和复跨场域互动模式;数字平台的互动模式决定了其治理机制,并呈现出多样化的特点,从而要求有相对应的保障机制。文章构建了一个平台研究的系统性理论框架,为推动数字平台领域研究、数字平台健康持续发展以及政府有效精准地规制数字平台提供了新思路。

Structural Stress Monitoring and FEM Analysis of the Cutting Operation of the Main Bracket of A Semi-Submersible Platform

For a semi-submersible platform in repair, the eight old main brackets which connect columns with pontoons need to be replaced by new ones. In order to ensure the safety of the cutting operation of the old main bracket and calculate the initial stress condition of new main bracket, the structural stress monitoring of eight key spots is carried out, and then the calibrated finite element model is established according to the field monitoring results. Before cutting the main bracket and all associated structures, eight rectangular rosettes were installed, and a tailored cutting scheme was proposed to release the initial stress, in which the main bracket and associated column and pontoon plates were partly cut. During the cutting procedure, the strains of the monitoring spots were measured, and then the structural stress of the monitored spots were obtained. The stress variation characteristics at different spots during the initial cutting operation were shown and the initial stress condition of the monitored spots was figured out. The loading and support conditions of the semi-submersible platform were calibrated based on the measured initial stress condition, which made the finite element model more credible. The stress condition with the main bracket and associated structures being entirely cut out is analyzed by the Finite Element Method (FEM), which demonstrates the cutting operation to be safe and feasible. In addition, the calibrated finite element model can be used to calculate the initial stress condition of the new main bracket, which will be very helpful for the long-term stress monitoring on the main bracket.

平台型领导如何提升团队创新绩效——基于SEM与fsQCA的链式中介分析

为探究平台型领导对团队创新绩效的作用机制,选取团队学习氛围和知识场活性作为中介,团队心理安全作为调节,基于496位高新技术行业知识型员工样本,运用结构方程模型和模糊集定性比较分析两种方法检验理论模型。结果显示,平台型领导正向促进团队创新绩效,团队学习氛围和知识场活性在其中发挥链式中介作用;团队心理安全调节团队学习氛围与知识场活性之间的关系。以平台型领导、团队学习氛围、知识场活性和团队心理安全为前因条件、团队创新绩效为结果条件的模糊集定性比较分析结果支持以上结论,并得出提高团队创新绩效的两种前因组态模式,即“领导—成员互动模式”和“团队成员互动模式”。

我国数据反垄断规制实践及完善

当前,数据要素已成为与土地、劳动力、资本、技术并列的生产要素,其不仅融入生产生活的方方面面,也关系到以数据为核心要素的数字经济市场公平竞争环境的维系与发展。在实践中,我国已在立法层面针对数据行为制定了相关条款,且在执法层面也针对数据行为,特别是数据垄断进行了有力监管。但是,伴随以互联网平台为代表商业组织体和生产组织机制的数字经济新业态、新模式、新产业不断发展,以数据为要素形成的垄断行为变得多样且隐蔽,对以数据为核心要素的垄断行为进行有效监管仍是难题。究其原因主要在于数据相关的基础理论体系尚待健全、数据的法律属性尚未明晰以及相关数据基础设施不完善。面对数字经济发展中“三新”经济的不断涌现,亟需对数据垄断实行有效的常态化敏捷监管,包括但不限于行业监管与市场监管相结合、跨部门综合监管以及不断完善基础配套措施等,形成监管合力。此外,对数据要素的基础理论、数据流通交易、数据基础设施等领域的基础制度建构也应加快推进。

剖面风速下雨场分布特性及海洋平台雨载荷计算研究

海上浮式结构物不断向大型化发展,极端环境中大型海上浮式结构物的雨载荷已成为设计人员关注的焦点问题之一。本文基于离散粒子模型,开展风驱雨场运动预报,量化雨场空间特征参数分布规律;推导结构雨载荷的计算公式,完成海洋平台不同风速和降雨强度组合工况下雨载荷的预报。研究表明:采用DNV风剖面和Davenport风谱作用下的海洋平台雨载荷服从Gamma分布;相较于平均风载荷,当降雨强度R=800 mm/h时,雨载荷三一值占比为5.07%,最大值占比为8.87%;当降雨强度R=20 mm/h,雨载荷三一值占比为0.36%,最大值占比为0.6%。本文研究成果可为海上结构物及其系泊系统设计提供指导。

桑托斯盆地盐下孤立碳酸盐台地沉积建造与深水大油田

针对桑托斯被动陆缘盆地深水盐下碳酸盐岩储层分布特征及大油田成藏规律不清的难题,综合利用地质、地震及岩心等数据资料,通过早白垩世原型盆地与岩相古地理恢复重建,提出盐下碳酸盐岩沉积建造受控于坳间断隆型和坳中断凸型两类孤立台地。坳间断隆型孤立台地分布于现今盐下坳间隆起带上,建造于早期陆内和陆间裂谷两个原型阶段继承性发育的单断式和双断式垒式断块上,早白垩世陆内裂谷晚期沉积的ITP组介壳灰岩和陆间裂谷早期沉积的BVE组微生物灰岩为连续建造;坳中断凸型孤立台地分布于现今盐下坳陷带中,建造于早期陆内裂谷原型阶段火山岩建隆所形成的凸起带上,发育BVE组微生物灰岩。两类孤立台地灰岩所形成礁滩体均具有储层厚度大、物性好的特点。结合盐下已发现大油田解剖,发现两类台地均可形成大型构造-岩性复合圈闭,周缘为优质湖相和潟湖相烃源岩环绕,上覆为巨厚的优质蒸发盐岩盖层高效封堵,形成了“下生中储上盖”式最佳生储盖组合关系,油气富集程度高。已发现大油田均为具有统一压力系统的底水块状油田,且均处于充满状态。未来勘探重点目标是西部隆起带和东部隆起带南段上的坳间断隆型孤立台地及中央坳陷带中的坳中断凸型孤立台地。该项研究成果为在桑托斯被动陆缘盆地超前选区选带、新项目评价及中标区块探区勘探部署提供了重要依据,也为今后在全球被动大陆边缘盆地深水勘探战略选区提供借鉴。

海上高压气田无人井口平台集输工艺流程方案比选设计

针对某海上高压气田井口压力高、井口温度低、油品凝点高、节流后易出现水合物和出油管线容易冻堵的问题,结合不同生产井节流后的压力,设置不同压力体系井口加热器以满足流体输送要求。文章研究了两种不同高压气田无人平台工艺流程方案:加热器部分降压设计方案和全部降压设计方案,比较了两种方案的技术特点及经济性,最终推荐高压气田无人井口平台采用加热器部分降压设计的工艺流程方案。

海上石油多台套大型压缩机平台总体布置研究

在海上平台建设中,总体布置的设计效果直接影响平台的运行效率与维护成本,但目前涉及到总体布置尤其是包含多台压缩机的布置研究较少。因此,从工艺流程、总图布置及安全运行等因素考虑,以渤海油田某凝析气田区块海上中心处理平台为例,针对其上部组块,进行多台套大型压缩机的平台总体布置研究。研究认为,海上平台压缩机布置应综合考虑工艺、安全、结构、操作及环保等因素,合规布置消防设施,并兼顾协同运行的结构稳定特性。该处理平台压缩机集中布置在中层甲板中心区域,成橇对称分布,设有H60防火墙、维修通道、逃生通道及雨淋喷管等,可以实现压缩机系统生产、安全、环保和操作的最佳平衡。同时,对于空间足够的平台,建议在满足工艺需求前提下,考虑将压缩机分散和分层错位布置,以更好地保障设备安全运行,识别和预防潜在危险。

基于信息采纳模型的机器学习领域科学数据重用影响因素研究

本文基于信息采纳模型构建了机器学习领域科学数据重用影响因素模型,并选择了开放科学社区平台和科学数据共享平台两种类型的代表性平台进行数据采集,实证了数据集内容质量和数据源可信性对科学数据重用的影响,以及平台类型在数据源可信性对科学数据重用影响中的调节作用。本研究对完善科学数据平台建设、促进科学数据重用具有重要意义。

小型农田原状土样采集机器人系统研发与测试

农业机器人是农业机械领域的研究热点之一。国内外对温室/农田/果园作业(除草、施肥、喷药、采摘等)机器人移动平台的研究已取得初步成果,但对农田土样采集机器人移动平台的研究鲜有出现。在土壤的物理力学特性研究过程中,原状土壤样品的采集是一个重要前提。如果土样的原状度无法保障,后期实验室物理力学测试分析难以得出准确的研究结果。本研究针对这一问题,研发了一台结构紧凑、通过性强、取土质量好、取土效率高的农田土壤采集机器人移动平台,给出了机械系统、控制系统设计方案,并开展了初步的田间试验研究。本研究的主要内容如下:(1)机器人移动平台本体设计方面,确定了差速转向的转向方式;进行了机械系统设计,完成了相关硬件选型分析和控制系统设计以及软件编写。移动平台轴距为960 mm、轮距为600 mm,轮毂电机功率1000 W,实现了基于调速转把和遥控手柄的移动平台协调运动控制,满足试验要求。(2)土样采集装置方面,对分段原状取土装置进行了设计。通过对比分析选用液压传动作为动力源和直压旋入式入土方式。通过理论分析确定了取土器主要技术参数,并对其入土关键部件进行有限元分析,验证了其结构参数设计的合理性。(3)通过田间试验,考察整机的移动性能和取土质量。移动性能测试试验结果表明:最大垂直越障高度80 mm,最大爬坡坡度35°。土样抗剪强度检测试验结果表明:在获取0~200 mm深度土样时,环刀法和新系统所取土样的内摩擦角方差在0.05的置信水平下,P值等于0.866;在获取0~100 mm和100~200 mm深度土样时,环刀法和取土装置所取土样的凝聚力方差在0.05的置信水平下,P值分别为0.145和0.717。取土效率对比试验结果表明:该取土装置完成一次取土仅需3~5 min。

基于微型槽和充氦气的惯性平台散热效果分析

惯性平台系统温度过高和剧烈变化是影响惯性导航系统导航精度的重要因素。为提升惯性平台系统的散热能力,提出了基于微型槽和充氦气的改进散热方法,并对散热效果进行分析。以某平台系统结构为对象,根据惯性平台系统传热机理,分析了当前惯性平台散热能力较差的原因。针对微型槽增大面积、填充氦气等散热方法开展数值仿真分析,并通过缩比样件的散热实验进行验证。实验结果表明,在强迫对流的基础上将两种方法结合使用,可使平台温度较改进前降低9.7℃,有效证明了两种散热方法的可行性及散热效果,为后续惯性平台系统的热设计提供指导。

大气协同观测网络与大数据平台建设

野外科学观测研究站是重要的国家科技创新基地之一,也是国家创新体系的重要组成部分。面向大气科学研究对第一手野外观测数据的迫切需求,本文在充分调研中国科学院大气物理研究所野外观测台站的基础上,详细阐述了“大气协同观测网络与大数据平台建设”项目的科学意义、研究内容、实施方案、预期成果与展望等。该项目拟通过顶层设计和优化布局,在有限投入的情况下最大限度地挖掘和利用现有各野外台站资源优势,进行联网协同观测试验,研发时空连续、高精度、高质量的大数据产品,为地球系统模式中关键物理过程参数化方案的改进和优化提供第一手宝贵的数据支撑,服务于国家科技原始创新战略。

钢轨调频阻尼器质量分布与性能研究

为研究减振块中谐振质量分布对钢轨调频阻尼器动力性能的影响,采用数值仿真与平台试验相结合的方法,对比分析不同谐振质量体分布下的钢轨调频阻尼器在典型频率和钢轨振动衰减率方面的差异,并分别选取2个试验段,采用现场测试的方法对钢轨调频阻尼器在减振垫浮置板轨道、减振扣件轨道结构下的钢轨振动以及轨旁噪声控制效果进行分析。研究结果表明:减振块中质量体的分布影响减振块的模态频率、有效频段和分频吸振效能,上层质量体及邻近弹性层厚度确定了垂/横向1阶频率,近轨侧弹性层厚度及总质量确定了吸振能力最高的频率。钢轨调频阻尼器的模态频率与试验平台垂向振动衰减率峰值频率和衰减率增加的显著频段一致性较好,可根据模态频率和参振质量比对减振块质量分布进行优化。经平台试验,前十五阶模态参振质量低与高的两款钢轨调频阻尼器安装后,钢轨振动衰减率最大值由安装前的0.53dB/m分别提升至3.54dB/m和4.07dB/m,钢轨垂向振动衰减率分频最大增加率分别为1143%和2023%。由现场测试结果可知,安装调频钢轨阻尼器可降低减振垫浮置板轨道1~1000 Hz频段钢轨振动加速度总级值5.6 dB,降低波磨主频处分频振级2.2~5.8 dB,并有效降低钢轨表面粗糙度发展速度;安装后可降低高等级减振扣件轨道轨旁噪声6.1 dB(A)。研究成果可为钢轨调频阻尼器的结构设计及优化提供参考。

高水头可逆式水轮机空载工况流动稳定性分析

当水泵水轮机处于空载工况下转动时,其运行状态直接关乎机组的并网性能及安全稳定性。为探究抽水蓄能机组在特殊工况下运行稳定性问题,以国内某高水头可逆式水轮发电机组为研究对象,对三种不同开度下的水泵水轮机空载工况进行数值模拟计算,结合机组内部流场状态和压力脉动传播规律,研究分析影响机组稳定性的特殊流动现象。在与特性曲线对照验证的基础上,计算结果表明:空载工况下导叶开度从小至大变化过程中,转轮内部涡旋分布由叶片吸力面向压力面逐渐发展;由于流动对称性条件被破坏,大开度条件下的旋转失速现象更为明显,并与动静干涉共同作用后导致转轮内部压力脉动振幅在接近进口的下游流道处达到最大。因此,需避免机组长期在较大开度的空载工况下运行,并在维护检修过程中注意靠近转轮叶片进口下游侧的结构应力分布。