90 resultados para submarine pipeline


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介绍了7000米载人潜水器推进系统的组成和推进器布置,描述了潜水器控制分配问题,对推进器推力和期望控制量进行了归一化处理.根据载人潜水器的推进器布置,建立了系统的控制分配模型,设计了推进器故障容错处理策略,研究了基于推力最小二范数的载人潜水器控制分配求解方法.采用基于伪逆矩阵与定点分配的混合控制分配求解算法,在半物理仿真平台上实验验证了控制分配求解算法的正确性和有效性.

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以7000m载人潜水器为研究对象,分析了潜水器的推进系统,并给出了6自由度推力转换模型,重点讨论了载人潜水器控制分配的优化问题.结合7000m载人潜水器的推进器布置和推进器特点,设计了优化准则代价函数,采用序列二次规划(sequential quadratic programm ing,SQP)算法求解了载人潜水器的非线性控制分配问题,通过半物理仿真平台实验验证了本文提出的控制分配算法的正确性和有效性.yh

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介绍了一类载人潜水器导航系统的组成,接着阐述了基于工业以太网的信息采集模块.由于载人潜水器动力学模型存在未建模扰动以及各种传感器存在不同程度的误差,需要采用卡尔曼滤波器(KF)等方法进行数据滤波,最后将滤波后的数据用于该类载人潜水器的导航研究.半物理仿真平台结果表明,载人潜水器的导航精度得到了大幅度提高.

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介绍了一种用于WAGO750-842以太网节点及系列模块与PC机之间的一种通用而又简便的通讯方法,该方法能够使PC机与WAGO750系列模块方便地进行数据交换,从而达到计算机对控制对象进行信息采集和控制输出的目的。该方法已在载人潜水器控制系统中得到成功应用,效果良好。

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介绍了载人潜水器的构成及推进器的布置,在此基础上导出了载人潜水器的推力分配方程。阐述了载人潜水器的运动控制。最后,将运动控制系统在载人潜水器半物理仿真平台上进行了验证,运动控制效果良好。

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介绍了基于工业以太网的载人潜水器的数据采集与监控系统。简要地阐述了载人潜水器的重要性。详细地描述了该系统的硬件结构及各智能节点的特点,并对系统中各层所实现的功能进行了详细的介绍。目前,该系统已在实验室进行了实验,实验效果良好。

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利用ROV代替潜水员进行潜艇供排气管对接作业是援潜救生的发展趋势,其中供排气管对接技术是为失事艇员提供生命保障的关键技术。由于水下作业环境比较复杂以及水下作业难度大等特点,人工遥控ROV进行援潜对接供排空气管作业过程中,还停留在只是能够打开潜艇供排气系统花甲板盖的工作上,还没有实现对类似接通供排空气管精确作业的工作。受到海流、风浪、失事潜艇周围较大涡流、供排气管的拖曳阻力、水下可视条件以及高精度定位等因素的限制,作业任务越复杂,要求ROV系统上机械手精确定位精度越高,操纵的难度也越大,由人工操作很难实现。在现有ROV人工操作的基础上,使ROV系统具有自主作业功能,更能发挥其在对接空气管作业中的能力,提高作业效率,缩短救援时间,因此本文在现有ROV基础上扩展预编程自主控制驾驶功能模块即ROV-A系统,借助预编程技术ROV-A系统在对接空气管作业中的一些特殊任务时能够实现自主作业功能。 本文结合中国科学院沈阳自动化研究所水下机器人中心未来援潜救生关键技术研究内容,针对为失事潜艇接通空气管作业中的一些关键技术,开展基于具有自主作业能力的ROV-A系统自主作业方法研究,深入研究了具有自主作业能力ROV-A系统的运动规划与协调控制技术以及水下作业力控制技术,以实现高精度的机械手末端位置控制与期望力跟踪;针对潜艇供排气系统的已知结构研究了水下目标定位技术,为对接空气管的特定需求发展具有自主作业能力的水下作业技术提供理论依据。重点研究针对系统特点的运动规划与多性能指标实现归一化问题;研究基于系统动力学模型误差的系统位姿控制问题;研究基于阻抗力控制水下作业目标定位问题;在系统运动规划与控制研究的基础上,研究能实现机械手末端精确轨迹跟踪的控制策略问题以及力控制问题。本论文研究内容如下: (1)根据ROV-A系统特点,从描述系统的空间位置和姿态着手,研究了ROV-A系统的空间运动学与基于Kane方法的动力学,得出载体基座自由运动模式的系统空间运动数学模型,为论文后续研究工作奠定了基础。 (2)针对对接空气管作业中的一些高精度和复杂的作业,研究了系统作业时的运动规划问题。针对系统运动学冗余、作业规划约束性能指标多,例如机械手可操作性,关节限制,载体的姿态,避障等等,结合梯度投影法和最小范数伪逆矩阵法以及任务优先逆运动学方法,引入模糊控制技术,将模糊控制的定性知识表达与任务优先逆运动学算法相结合,以水下作业末端位置控制及轨迹跟踪为前提,对系统运动分配、关节限位、避免奇异有无海流下的系统性能优化等运动规划进行了研究,仿真证明运动规划算法的有效性。 (3)研究了基于动力学模型的系统基本控制问题。针对系统动力学模型的复杂性和不精确性,在基于载体输出反馈控制的基础上,设计了基于输出反馈自适应控制算法,通过自适应学习的方式直接逼近系统动力学方程状态量之间的非线性关系,在外界不停扰动下逐渐提高系统的控制精度;基于Lyapunov稳定性理论,证明了存在外界干扰和自适应逼近误差条件下ROV-A系统控制器的闭环稳定性;通过仿真实验验证控制系统的有效性,为系统的控制提供了一种新思路。同时在基于位置运动控制的基础上引入了力控制,通过对常规PID外环力控制器基础上的改进,在系统离线规划的前提下实现力与位置控制的解耦,通过仿真验证期望力的稳定跟踪。 (4)研究了基于ROV-A系统阻抗力控制的水下矩形围壁环境约束的位置定位方法。通过在对具有先验知识的矩形围壁环境约束的学习理解基础上,应用外部阻抗力控制环包容内部位置运动控制环的控制策略。利用力传感器的反馈信息变化确定系统末端执行器与约束环境的接触特征点,根据环境的先验知识推理出环境定位信息。通过计算机仿真实验验证了水下具有先验知识环境的定位方法和ROV-A系统的控制策略的有效性。仿真结果证明定位方法和控制策略是可行的。 (5)结合系统控制,分析了系统在为失事潜艇对接空气管作业中的恒定和时变两种期望力输入作业模式,提出了基于在线运动规划下外部力控制环包容内部位置环控制方法,利用ROV-A系统完成了为失事潜艇自主对接空气管中两个典型作业。介绍了整个控制方法的组成和执行过程,分析了综合控制策略,最后通过仿真实验分析了综合力控制方法的性能,包括恒力和时变期望力输入进行了深入研究。

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本文介绍了AUV 跟踪水下管道的一种方法,讨论了几种跟踪方式的优、缺点,给出了控制系统原理图和试验结果

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介绍了管线钢硫化物应力腐蚀裂开危险性智能探测仪的设计、结构和检测结果。该检测仪具有数据采集、存储处理、逻辑判断和现场制表打印输出评价/判断等功能,对及时发现和消除含硫油气管线的隐患,以防止恶性破坏事故的发生有重要意义。

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在研究快速傅里叶变换(FFT)算法的基础上,根据FPGA性能高、灵活性强、速度快的特点,提出了高效的基4-FFT处理器的实现方法。数据存储采用分块存储的方法,大大提高了存取速度。数据寻址采用新型的地址产生方法,可并行产生所需数据地址。同时,在蝶形单元的设计中很好的将并行运算技术和流水线技术相结合了起来,又进一步提高了运算速度。测试结果表明,时钟在50MHz时完成1024点FFT的时间为25.6μs,满足了应用实时性的要求。

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Livingston Island, the second island of South Shetland Island, constains Mesozoic-Cenozoic basement, Mesozoic-Cenozoic volcanic sequences, plutonic intrusions and post-subduction volcanic rocks, which document the history and evolution of an important part of the South Shetland Islands magmatic arc. The sedimentary sequence is named the Miers Bluff Formation (MBF) and is interpreted as turbidite since the first geological study on South Shetland Islands, and is interpreted as turbidite. It base and top are not exposed, but a thickness of more than 3000m has been suggested and seems plausible. The turbidite is overlain by Mid - Cretaceous volcanic rocks and intruded by Eocene tonalites. The age of the Miers Bluff Formation is poorly constrained Late Carboniferous -Early Triassic. Sedimentary Environment, tectonic setting and forming age of sedimentary rocks of the Miers Bluff Formation were discussed by means of the methods of sedimentology, petrography and geochemistry, combinig with the study of trace fossils and microfossil plants. The following conclusions are obstained. A sedimentary geological section of Johnsons Dock is made by outside measuring and watching, and then according the section, the geological map near the Spanish Antarctic station was mapped. Four pebbly mudstone layers are first distinguished, which thickness is about 10m. The pebbly mudstone is the typical rock of debris flow, and the depostional environment of pebbly mudstone may be the channel of mid fan of submarine fan. The sedimentsry structural characteristics and size analysis of sandstones show the typical sedimentary feature of turbidity flow and the Miers Bluff Formation is a deep-water turbidite (include some gravity-flow sediments). The materials of palaeocurrents suggest the continental slope dip to southeast, and indicate the provenance of turbidity sediment in the northwest area. By facies analysis, six main facies which include seven subfacies were recognized, which are formed in mid-fan and lower-fan of submarine, meanwhile, the sedimentary features of each facies and subfacies are summarized. The study of clastic composition, major elements, trace elements and rare earth elements indicates the forming setting of the Miers Bluff Formaton is active continental margin and continental island arc and the provenance is dissected magmatic arc which main composition is felsic gneiss. Many trace fossils of the whole succession were found in the turbidites of the Miers Bluff Formation. All these trace fossils are deep sea ichnofossils. There are fifteen ichnogenus, sixteen ichnospecies. Moreover, a new trace fossil was found and a new ichnogenus and new ichnospecies was proposed - Paleaichnus antarctics ichnogen, et ichnosp, nov.. Except the new ichnogenus and ichnospecies, others had been found in deep-sea flysch turbidites. Some are in mudstone and are preserved in the cast convex of overlying sandstone sole, they formed before turbidity flows occurred and belong to the high-different Graphoglyptida of fiysch mudstone. Others as Fucusopsis and Neonereites are preserved in sandstones and stand for trace assemblages after turbidity sedimentation. These trace fossils are typical members of abyssal "Nereites" ichnofacies, and provide for the depositional environment of the Miers Bluff Formation. Fairly diverse microfossil plants have been recovered from the Miers Bluff Formation, Livingston Island, including spores, pollen, acritarchs, wood fragments and cuticles. Containing a total of about 45 species (forms) of miospores, the palynofiora is quantitatively characterized by the dominance of non-striate bisaccate pollen, but spores of pteridophytes and pollen of gymnosperms are proportionate in diversity. It is somewhat comparable to the subzone C+D of the Alisporites zone of Antarctica, and the upper Craterisporites rotundus zone and the lower Polycingulatisporites crenulatus zone of Australia, suggesting a Late Triassic (possibly Norian-Rhaetian) age, as also evidenced by the sporadic occurrence of Aratrisporites and probable Classopollis as well as the complete absence of bisaccate Striatiti. The parent vegetation and paleoclimate are preliminarily deduced. At last, the paper prooses the provenance of sedimentary rocks of the Miers Bluff Formation locates in the east part to the southern Chile(or Southern South American). In the Triassic period, contrasting with New Zealand, Australia and South American of the Pacific margin of Gondwanaland, the Miers Bluff Formation is deposited in the fore-arc basin or back-arc basin of magmatic arc.

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Natural gas pays more important role in the society as clean fuel. Natural gas exploration has been enhanced in recent years in many countries. It also has prospective future in our country through "85" and "95" national research. Many big size gas fields have been discovered in different formations in different basins such as lower and upper Paleozoic in Erdos basin, Tertiary system in Kuche depression in Tarim basin, Triassic system in east of Sichuan basin. Because gas bearing basins had been experienced multiple tectogenesis. The characteristics of natural gases usually in one gas field are that they have multiple source rocks and are multiple maturities and formed in different ages. There has most difficult to research on the gas-rock correlation and mechanism of gas formation. Develop advanced techniques and methods and apply them to solve above problems is necessary. The research is focused on the critical techniques of geochemistry and physical simulation of gas-rock correlation and gas formation. The lists in the following are conclusions through research and lots of experiments. I 8 advanced techniques have been developed or improved about gas-rock correlation and gas migration, accumulation and formation. A series of geochemistry techniques has been developed about analyzing inclusion enclave. They are analyzing gas and liquid composition and biomarker and on-line individual carbon isotope composition in inclusion enclave. These techniques combing the inclusion homogeneous temperature can be applied to study on gas-rock correlation directly and gas migration, filling and formation ages. Technique of on-line determination individual gas carbon isotope composition in kerogen and bitumen thermal pyrolysis is developed. It is applied to determine the source of natural is kerogen thermal degradation or oil pyrolysis. Method of on-line determination individual gas carbon isotope composition in rock thermal simulation has being improved. Based on the "95"former research, on-line determination individual gas carbon isotope composition in different type of maceral and rocks thermal pyrolys is has been determined. The conclusion is that carbon isotope composition of benzene and toluene in homogenous texture kerogen thermal degradation is almost same at different maturity. By comparison, that in mixture type kerogen thermal pyrolysis jumps from step to step with the changes of maturity. This conclusion is a good proof of gas-rock dynamic correlation. 3. Biomarker of rock can be determined directly through research. It solves the problems such as long period preparing sample, light composition losing and sample contamination etc. It can be applied to research the character of source rock and mechanism of source rock expulsion and the path of hydrocarbon migration etc. 4. The process of hydrocarbon dynamic generation in source rock can be seen at every stage applying locating observation and thermal simulation of ESEM. The mechanism of hydrocarbon generation and expulsion in source rock is discussed according to the experiments. This technique is advanced in the world. 5. A sample injection system whose character is higher vacuum, lower leaks and lower blank has been built up to analyze inert gas. He,Ar,Kr and Xe can be determined continuously on one instrument and one injection. This is advanced in domestic. 7. Quality and quantity analysis of benzene ring compounds and phenolic compounds and determination of organic acid and aqueous gas analysis are applied to research the relationship between compounds in formation water and gas formation. This is another new idea to study the gas-rock correlation and gas formation. 8. Inclusion analysis data can be used to calculate the Paleo-fluid density, Paleo-geothermal gradient and Paleo-geopressure gradient and then to calculate the Paleo-fluid potential. It's also a new method to research the direction of hydrocarbon migration and accumulation. 9. Equipment of natural gas formation simulation is produced during the research to probe how the physical properties of rock affect the gas migration and accumulation and what efficiency of gas migrate and factors of gas formation and the models of different type of migration are. II study is focused on that if the source rocks of lower Paleozoic generated hydrocarbon and what the source rocks of weathered formation gas pool and the mechanism of gas formation are though many advanced techniques application. There are four conclusions. 1.The maturity of Majiagou formation source rocks is higher in south than that in north. There also have parts of the higher maturity in middle and east. Anomalous thermal pays important role in big size field formation in middle of basin. 2. The amount of gas generation in high-over maturity source rocks in lower Paleozoic is lager than that of most absorption of source rocks. Lower Paleozoic source rocks are effective source rocks. Universal bitumen exists in Ordovician source rocks to prove that Ordovician source rocks had generated hydrocarbon. Bitumen has some attribution to the middle gas pool formation. 3. Comprehensive gas-rock correlation says that natural gases of north, west, south of middle gas field of basin mainly come from lower Paleozoic source rocks. The attribution ratio of lower Paleozoic source rocks is 60%-70%. Natural gases of other areas mainly come from upper Paleozoic. The attribution ratio of upper Paleozoic source rocks is 70%. 4. Paleozoic gases migration phase of Erdos basin are also interesting. The relative abundance of gasoline aromatic is quite low especially toluene that of which is divided by that of methyl-cyclohexane is less than 0.2 in upper Paleozoic gas pool. The migration phase of upper Paleozoic gas may be aqueous phase. By comparison, the relative abundance of gasoline aromatic is higher in lower Paleozoic gas. The distribution character of gasoline gas is similar with that in source rock thermal simulation. The migration phase of it may be free phase. IH Comprehensive gas-rock correlation is also processed in Kuche depression Tarim basin. The mechanism of gas formation is probed and the gas formation model has been built up. Four conclusions list below. 1. Gases in Kuche depression come from Triassic-Jurassic coal-measure source rocks. They are high-over maturity. Comparatively, the highest maturity area is Kelasu, next is Dabei area, Yinan area. 2. Kerogen thermal degradation is main reason of the dry gas in Kuche depression. Small part of dry gas comes from oil pyrolysis. VI 3.The K12 natural gas lays out some of hydro-gas character. Oil dissolved in the gas. Hydro-gas is also a factor making the gas drier and carbon isotope composition heavier. 4. The mechanism and genesis of KL2 gas pool list as below. Overpressure has being existed in Triassic-Jurassic source rocks since Keche period. Natural gases were expulsed by episode style from overpressure source rocks. Hetero-face was main migration style of gas, oil and water at that time. The fluids transferred the pressure of source rocks when they migrated and then separated when they got in reservoir. After that, natural gas migrated up and accumulated and formed with the techno-genesis. Tectonic extrusion made the natural gas overpressure continuously. When the pressure was up to the critical pressure, the C6-C7 composition in natural gas changed. The results were that relative abundance of alkane and aromatic decreased while cycloalkane and isoparaffin increased. There was lots of natural gas filling during every tectonic. The main factors of overpressure of natural gas were tectonic extrusion and fluid transferring pressure of source rocks. Well preservation was also important in the KL2 gas pool formation. The reserves of gas can satisfy the need of pipeline where is from west to east. IV A good idea of natural gas migration and accumulation modeling whose apparent character is real core and formation condition is suggested to model the physical process of gas formation. Following is the modeling results. 1. Modeling results prove that the gas accumulation rule under cap layer and gas fraction on migration path. 2. Natural gas migration as free phase is difficult in dense rock. 3. Natural gases accumulated easily in good physical properties reservoirs where are under the plugging layer. Under the condition of that permeability of rock is more than 1 * 10~(-3)μm~(-1), the more better the physical properties and the more bigger pore of rock, the more easier the gas accumulation in there. On the contrary, natural gas canonly migrate further to accumulate in good physical properties of rock. 4. Natural gas migrate up is different from that down. Under the same situation, the amount of gas migration up is lager than that of gas migration down and the distance of migration up is 3 times as that of migration down. 5. After gas leaks from dense confining layer, the ability of its dynamic plug-back decreased apparently. Gas lost from these arils easily. These confining layer can confine again only after geology condition changes. 6. Water-wetted and capillary-blocking rocks can't block water but gases generally. The result is that water can migrate continuously through blocking rocks but the gases stay under the blocking rocks then form in there. The experiments have proved the formation model of deep basin gas.

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Kela-2 gas field in Tarim Basin is the main supply source for West-to-East Pipeline project, also the largest abnormally-pressured gas field discovered in China currently. The geological characterization, fine geological modeling and field development plan are all the world-class difficult problems. This work includes an integrated geological and gas reservoir engineering study using advanced technology and approaches, the scientific development plan of Kela-2 gas field as well as the optimizations of the drilling, production and surface schemes. Then, it's expected that the Kela-2 gas field can be developed high-efficiently.Kuche depression is one part of the thrust belt of the South Tianshan Mountains, Kela-2 field is located at the Kelasu structural zone in the north of Kuche depression. The field territory is heavily rugged with deeply cut gullies, complex geological underground structure, variable rock types, thrust structure development. Therefore, considerable efforts have been made to develop an integrated technique to acquire, process and interpret the seismic data in complicated mountain region. Consequently a set of seismic-related techniques in the complicated mountain region has been developed and successfully utilized to interpret the structure of Kela-2 gas field.The main reservoir depositional system of Kela 2 gas field is a platform - fan delta - braided river system. The reservoir rocks are medium-fine and extremely fine grained sandstones with high structure maturity and low composition maturity. The pore system structure is featured by medium-small pore, medium-fine throat and medium-low assortment. The reservoir of Kela-2 gas field is characteristic of medium porosity and medium permeability. The pay zone is very thick and its lateral distribution is stable with a good connection of sand body. The overpressure is caused mainly by the strongly tectonic squash activities, and other factors including the later rapid raise and compartment of the high-pressure fluid, the injection of high-pressure fluid into the reservoir.Based on the deliverability tests available, the average binomial deliverability equation is provided applicable for the overall field. The experimental results of rock stress-sensitive tests are employed to analyze the change trend of petrophysical properties against net confining stress, and establish the stress-based average deliverability equation. The results demonstrate the effect of rock deformation on the deliverability is limited to less than 5% in the early period of Kela-2 gas field, indicating the insignificant effect on deliverability of rock deformation.In terms of the well pattern comparisons and development planning optimizations, it is recommended that the producers should be located almost linearly along the structural axis. A total of 9 producers have a stable gas supply volume of 10.76 BCMPY for 17 years. For Kela-2 gas field the total construction investment is estimated at ¥7,697,690,000 RMB with the internal earning rate of 25.02% after taxation, the net present value of ¥7,420,160,000 RMB and the payback period of 5.66 years. The high profits of this field development project are much satisfactory.

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An industrial scale dehydration process based on hollow fiber membranes for lowering the dew point of natural gas is described in this paper. A pilot test with the feed flux scale of 12x10(4) Nm(3)/d was carried out. Dew points of -8 degreesC-13 degreesC at a gas transport pressure in the pipeline of 4.6M Pa and methane recovery of more than 98% were attained. The water vapor content of the product gas could be maintained around 0.01 vol% during a continuous run of about 700 hours. The effects of feed flux and operation pressure on methane recovery and water vapor content were also investigated. Additionally, some auxiliary technologies, such as a full-time engine using natural gas as fuel and the utilization of vent gas in the process, are also discussed. A small amount of the vent gas from the system was used as a fuel for an engine to drive vacuum pumps, and the heat expelled from the engine was used to warm up the natural gas feed. The whole system can be operated in a self-sustainable manner from an energy point of view, and has a relatively high efficiency in the utilization of natural gas.