Experimental study on the nonlinear pressure acting on a high-speed vessel in irregular waves

The present study focuses on the nonlinear behavior of pressure on the hull surface of a high-speed vessel in irregular waves, particularly the pressure responses of alternately wet and dry areas near the waterline and on the bow zone. The vessel has high deadrise angles that may be subject to slight impact and water pile-up effects. A series of experiments in regular and irregular head waves were conducted, and the validity of applying Volterra modeling was investigated. In a previous article using experimental data in regular waves, it was confirmed that the approximate third-order Volterra model adequately simulated the variation of pressure responses in regular waves of different steepness up to a wave amplitude with a wavelength ratio of 0.01, even for the highly nonlinear pressures acting on the abovementioned areas of the hull surface. In this article, further validation for the second part of the study was obtained using experimental data in irregular waves. The frequency response functions obtained from the previous study’s experimental data in regular waves were applied to the third-order Volterra model by combining the input of irregular waves to simulate the responses in irregular waves of sea state five. Then, the spectra and statistics were analyzed. For the motions, accelerations, and pressure responses in irregular waves (as well as for the simulated time histories) variance spectra and statistics such as cumulative distributions of peak values and probability density functions were compared with the experimental results. It was confirmed that even for highly nonlinear and non-Gaussian pressures on the abovementioned areas of the hull surface, the approximate third-order Volterra model simulates the pressure responses in irregular head waves up to a sea state of five with adequate accuracy on deterministic and statistical bases.     

长江深水砂被铺设施工工艺

因与先期软体排护底工程有重合区域,针对区域内存在块石及透水框架的问题,为避免对铺设的软体排造成破坏,在现有铺排船铺设软体排的基础上,采用铺排船进行深水砂被铺设处理,达到了阻隔碎石垫层、抛石等挤入淤泥和部分的水平排水的目的。     

液压销孔式升降系统结构分析

升降系统是自升式风电安装船的核心设备,其结构稳定性是其平台和桩腿顺利实现升降的保证。本文以某自升式风电安装船的液压销孔式升降系统为研究对象,采用有限元方法建立其部件的结构模型,给出结构分析的载荷及边界条件,并运用有限元分析软件Ansys对各工况下的受力与变形进行求解,对计算结果进行分析和评估。研究结论为升降系统的设计与制造提供了理论指导,并为此类结构受力的设计计算提供参考。     

渔船稳性衡准分析与算法研究

我国有数量庞大的渔业船舶,其稳性对船舶安全生产、船型设计开发等方面产生重要影响。本文整理现行渔业船舶稳性衡准要求;分析稳性衡准数的数理实质;进而应用国内外普遍认可的总体设计软件NAPA进行渔业船舶稳性衡准数核算方法研究开发。有助于提高对渔业船舶稳性的认知水平和校核能力,亦可为具备类似衡准要求的其他船型设计研发及稳性校核工具开发提供借鉴。     

“泰鑫1”采选矿船的选矿系统支撑装置设计

本文对“泰鑫1”采选矿船的选矿系统支撑装置的功能和结构布置、强度校核等方面的设计进行了介绍,并对该装置设计中的关键技术进行阐述和总结,为此类装置在船上的应用提供设计参考。     

69.8m三用工作船的噪声预报与控制

对69.8 m三用工作船的主要噪声源进行优化控制,基于统计能量法进行舱室噪声预报,根据预报结果对目标舱室采取针对性降噪措施。实船验证结果显示,该船满足HAB入级要求,取得ABS证书。该研究方法和结论对于现阶段国内船厂所面临的降噪难题有较大的应用参考价值。     

局部加固改造技术在高桩码头中的应用

为适应经济社会发展,提高岸线资源利用率,提升企业竞争力,降低物流运输成本以及适应船舶的大型化,较多建于20世纪90年代的码头迫切需要对现有的码头设施进行加固改造,以满足码头安全运营的需要。通过对高桩码头结构局部加固改造方式特点分析,发现20世纪90年代建造的许多码头适合采用局部加固改造技术,并举例说明,为这一类型的码头结构加固改造设计和施工提供借鉴和参考。     

半潜驳改造为坐底式风电安装船的设计及应用研究

为解决现有海上风电安装设备的不足,将原“三航工5”半潜驳改造为坐底式风电安装船,并研制了一套船体结构应力监测系统,对国内某海上风场砂性地质条件引起的冲刷和船底掏空进行监控,实际工程应用表明改造后的船舶在安全性和工效上满足坐底安装风机的要求。     

休闲渔船的技术指标研究

休闲渔船是新生事物,目前没有统一的法律及专业性规范加以约束管理。对休闲渔船的定义、现状、功能及主尺度进行了介绍与讨论,对其技术指标进行深入研究,供休闲渔船的设计、建造、管理者参考。     

船模六自由度运动量的接触式测量

在系泊船模在波浪中的运动水工模型试验中,设计了一种试验测量仪器.该仪器可用于测量波浪作用下系泊船模的六自由度运动量.将6支拉绳式位移传感器固定在船模上方,每个传感器的拉绳均与下方的船模固定.船模晃动时会带动6根拉绳.根据6根拉绳长度变化和前一时刻船模的姿态,可以计算出船模运动的六自由度运动量.经波浪试验表明,该仪器可以很好地反应系泊船模的六自由度运动量,达到了预期的目的.