“天鲲号”超大型自航绞吸船辅钢桩门装置设计

针对自航绞吸船在艏部设置辅钢桩定位系统存在的影响航速等问题，“天鲲”号超大型自航绞吸挖泥船提出了在艏部设置钢桩门的解决方案。该解决方案不仅可以保持完整的艏部线型，减小航行阻力，而且还可以减小辅钢桩甲板作业空间。本文介绍了“天鲲”号辅钢桩门装置的设计方案，以及辅桩钢桩门结构设计，最后提出了辅钢桩门开闭油缸等关键设备的选型计算方法及选型结果。本文可为超大型自航绞吸式挖泥船的辅钢桩门装置的设计分析提供参考和设计思路。     

Research on the calculation method of penetration resistance of bucket foundation for offshore wind turbines

The cost of foundations for offshore wind turbines constitutes approximately 35% of the total cost of an offshore wind farm. The bucket foundations show significant potential due to their superior transportation and installation efficiencies compared to pile foundations, leading to potential cost savings for the foundation of up to 30%. For a bucket foundation to be installed successfully, the penetration resistance must be predicted. However, there is currently a lack of clarity on how to select a suitable calculation method for penetration resistance based on known geological parameters to guide construction. In order to evaluate the current methods of calculation for bucket foundation penetration resistance, this study combines theoretical calculation methods with two sets of practical measurement data from the field. The calculation methods of penetration resistance for bucket foundation are first reviewed and categorized. The applicability range of each method and the parameters needed for calculation are given. Next, according to the measured data in the process of penetration of bucket foundation on site, the evolution of compartment pressure, tilt angle, resistance and required suction in the process of penetration are analyzed. Finally, the reviewed methods are compared to the results of two practical projects in order to analyze the differences between them and make recommendations for the calculation technique. The findings can be used as a guide for calculating the bucket foundation's penetration resistance in complex geological conditions.     

进气冷却式回热燃气轮机循环数值模拟和分析

针对简单循环燃气轮机性能偏低且易受大气温度变化的影响，本文提出了一种由吸收制机徊汽轮机组成的新型循环－－进气冷却式回热式燃气机循环，对其建模进行数值模拟和分析。结果表明，此循环既能较大幅度提高燃气轮机装置的性能，又能有效地改善燃气轮机性能对大气温度变化的敏感性。     

耙吸挖泥船挖泥装舱和抽舱排放的一种分析方法

通过对耙吸挖泥船在挖泥装舱和抽舱排放作业时,船上吸排系统若干参数的分析,提出了一个确定吸排系统中泥泵、高压冲水、艏吹等分系统参数的方法,供有关人员参考.     

吸风循环式轨道吸污装置的吸污能力及能耗研究

针对轨道吸污装置吸污能力不足和污染周边环境的问题,提出吸风循环吸污的解决方案,即将吹风机产生的全部风量仅供给一侧吹嘴吹风吸污,将吸风机产生的排风供给另外一侧吹嘴吹风吸污,形成吸风机排风的循环利用,并通过调节风门开启的大小,调节吹风的风量和风速,从而增强轨道吸污装置吹风吸污的效果.基于流体力学,在忽略空气黏性力和密度变化以及不同流速气体混合时能量损失的前提下,对按照解决方案改进得到的吸风循环式轨道吸污装置吸污能力及能耗进行分析计算.结果表明:在作业速度为10 km· h-1时,吸风循环式轨道吸污装置能够吸净单层粒径分别达5 mm的铁屑和14.3 mm的石子；相比改进前的轨道吸污装置,吸收污物的最大粒径提高了7倍左右,污物吸净率高于98％；吸污作业功率节省74 kW,能耗下降2o％.     

耙吸挖泥船DP/DT控制算法研究

以耙吸挖泥船为应用背景,介绍了动力定位／动态跟踪的发展和现状,设计出基于模糊的PID控制算法来实现位置保持和按预定航迹疏浚。根据工程经验制定了符合耙吸挖泥船应用的模糊规则,同时通过Matlab及Simulink对其进行仿真。实验结果表明,该控制算法在环境力的影响下,DP／DT效果良好,满足工程实际需要。     

A method to predict the torsional resistance of suction caisson with anti-rotation fins in clay

Suction caisson foundations have been increasingly employed as a primary solution to support the offshore fixed- or mobile-structures. Due to harsh environment and complex force transferring of offshore structures, they are still being developed as to satisfy increasing requirements in strict working scenarios. One of emerging challenges is a torsion-governing failure, which has been observed in the oil and gas industry (i.e. significant multiple-inline-force-induced torsion) and in the renewable energy field (i.e. non-coplanar tensile force induced torsion). This paper introduces a novel suction caisson foundation, with anti-rotational fins assembled on the outer skin of caisson. By a comprehensive numerical study, the evolution from local to global failure as the fin numbers from single to multiple, is examined in the clayey soil deposit with effects of soil strength heterogeneity, fins dimension, installation process and foundation-soil interface considered. Based on these, a set of methods to estimate the ultimate torsional capacity of such novel caisson is proposed, which starts from the gain in capacity for a single fin, and evaluate the changes of gains in capacity as fin numbers, then identify the optimised anti-rotational capacity. Finally, three key parameters (i.e. the required fin numbers, the available anti-rotational capacity and the optimised anti-rotational capacity) with some critical considerations, recommendations and implications have been concluded for design practice.     

Monitoring of suction bucket jackets for offshore wind turbines: Dynamic load bearing behaviour and modelling

Suction bucket foundations for offshore wind turbines (OWT) have considerable advantages compared to conventional foundation types: Due to the installation process with dead weight and applied negative pressure, noise from pile driving can be completely avoided. In addition, the installation process of the whole substructure, consisting of the buckets connected to the jacket, can be carried out in one work step, which increases efficiency. A prototype of the suction bucket jacket was installed in the wind park ‘Borkum Riffgrund 1’ (North Sea) in August 2014. Due to the pre-installed and comprehensive measuring system, it was possible to monitor all installation and operating phases. The data analysis of a storm event show an amplitude and frequency-dependent behaviour of the soil stiffness and the suction bucket foundation without wind turbine. In the frequency range of the first and second eigenfrequency (0.2 Hz < f < 5 Hz), the system behaves linearly. Here, the Frequency Domain Decomposition is used for identification and monitoring. For the lower frequency band (0.05 Hz < f < 0.2 Hz) where higher forces and displacements occur, a non-linear multilayer perceptron is chosen to model the non-linear relations between measurements. By applying two mathematical models for the relevant frequency ranges, all the information from the measurement data can be used for system identification and novelty detection under varying environmental conditions.     

Effects of tension gap on the holding capacity of suction anchors

Suction anchors are popular anchoring solutions for station-keeping of offshore floating facilities. For the in-place holding capacity design of these anchors, there is a debate in practice regarding the possibility of developing a tension gap on the rear side of the anchor and how to account for it in design. This study is carried out to shed further light on this debate. Analytical and finite element analyses are reported in this study which investigate: i) the optimal padeye depths and the influencing factors, for both free gapping and no gapping interface conditions; ii) the effect of tension gap on the anchor's holding capacity when the padeye is placed at optimal depths; iii) the effect of tension gap on the anchor's holding capacity when the padeye is placed at non-optimal depths. Strategy to account for tension gap in practical design is provided.     

“新海旭”全球最大非自航重型绞吸挖泥船

本论文介绍了国内自2010年以来建成的四型有代表意义的非自航大型绞吸挖泥船和国外最大的两艘非自航绞吸挖泥船，可以看到国内自主研制能力已经步入国际领先行列。集成船舶设计通用原理和绞吸挖泥船专业疏浚设备开发技术，用图形的方式表示了该船型设计的主要方面。扼要介绍了“新海旭”的总布置、航区、动力配置、疏浚输送系统和钢桩台车定位系统等，并对大型绞吸挖泥船的作业航区、动力配置方案和疏浚输送系统生产能力等进行了探讨和分析。论文提出的绞吸挖泥船设计原理和对“新海旭”的技术状态介绍可供开发大型绞吸挖泥船参考。