Study of the Lift Force Induced by An Interceptor on A High-Speed Mono-Hull:The Affecting Factors and Estimation Formula

To find a better way to estimate the lift force induced by an interceptor on a high-speed mono-hull ship,a series of high-speed mono-hull ship models are designed and investigated under different conditions.Different lift forces are obtained by numerical calculations and validated by a model test in a towing tank.The factors that influence the force are the interceptor height,velocity,draft,and deadrise angle.The relationship between each factor and the induced lift force is investigated and obtained.We found that the induced lift mainly depends on the interceptor height and advancing velocity,and is proportional to the square of the interceptor height and velocity.The results also showed that the effects of the draft and deadrise angle are relatively less important,and the relationship between the induced lift and these two factors is generally linear.Based on the results,a formula including the combined effect of all factors used to estimate the lift force induced by the interceptor is developed based on systematic analysis.The proposed formula could be used to estimate the lift force induced by interceptors,especially under high-speed condition.

Finite element analysis on nut post structure of Three Gorges Project ship lift

A nonlinear finite element model of the nut post reinforced concrete （RC） structure of the safety mechanism in the Three Gorges Project （TGP） ship lift was built by ANSYS software. Some irregular structures such as the nut post and the rotary rod were divided by curved surface into a series of regular parts, and the structures were all meshed to hexahedron. Constraint equations were defined between two interfaces with different element sizes and mesh patterns. PRETS179 elements were used to simulate the preload in the tendons and the pre-stressed screws, and the loss of prestressing force was calculated. Five extreme load cases were analyzed. The stress of each part in the structure was obtained. The results indicate that the maximum compressive stress of concrete C35 is 24.13 MPa, so the concrete may be partially crushed; the maximum tensile stress of the grouting motar is 6.73 MPa, so the grouting motar may partially fracture; the maximum yon Mises stress of the rotary rod is 648.70 MPa, therefore the rotary rod may partially yield.

Structure Analysis of Locking Mechanism of Gear-Rack Typed Ship-Lift

Contact nonlinear theory was researched. Contact problem was transformed into optimization problem containing Lagrange multiplier, and unsymmetrical stiffness matrix was transformed into symmetrical stiffness matrix. A finite element analysis （FEA） model defining more than 300 contact pairs for long nut-short screw locking mechanism of a large-scale vertical gear-rack typed ship-lift was built. Using augmented Lagrange method and symmetry algorithm of contact element stiffness, the FEA model was analyzed, and the contact stress of contact interfaces and the von Mises stress of key parts were obtained. The results show that the design of the locking mechanism meets the requirement of engineering, and this method is effective for solving large stole nonlinear contact pairs.

Finite element and experimental analysis of pinion bracket-assembly of three gorges project ship lift

The pinion bracket-assembly(PBA) is a major part of three gorges project(TGP) ship lift drive system. The static strength,fatigue strength and stress distribution of hinge pin of PBA were analyzed by ANSYS, and the structure of PBA was optimized. The results show that after the optimization, the maximum comprehensive stress is 259.59 MPa, the maximum fatigue cumulative damage of weld joints is 0.94 and the maximum vertical deformation of hinge pin is 0.14 mm. The elastic deformation, hydropneumatic spring cylinder(HSC) load response and the vibration characteristics of PBA were studied by the bearing test when PBA bore the load caused by different water level errors. The results indicate that when the water level of ship chamber ranges from 3.4 m to 3.6 m,the vertical elastic deformation of the pinion shaft is between-8.58 and 10.50 mm. When upward outage-load(1580 k N) is imposed by the test-rack, the vertical elastic deformation of the pinion shaft is 13.42 and 14.07 mm and HSC load response is 795.80-800.80 k N. In the process of imposing load on the pinion by the test-rack, the maximum vibration amplitude and acceleration of PBA internal components are 0.37° and 2.67 rad/s2, respectively; the maximum impact on the pin caused by vibration is 19.89 k N; the pinion shaft vertical displacement and HSC load response do not fluctuate. There is a great difference between the frequency of meshing force of the pinion and the rack(1.06 Hz) and first-order natural frequency of PBA(8.41 Hz), thus PBA will not resonate.From all above, PBA meets the static strength and fatigue strength requirements. The vibration of PBA internal components has no effect on the vertical displacement of the pinion shaft, HSC load response and smooth operation of PBA. There is a liner relationship in the ratio of 2:1 between the thrust imposed by the test-rack and HSC load, thus HSC can limit the load imposed on the pinion.

Design and implementation of an expert system for remote fault diagnosis in ship lift

In this paper an expert system for remote fault diagnosis in the ship lift was developed by analysis of the fault tree and combination with VPN. The fault tree was constructed based on the operation condition of the ship lift. The diagnosis model was constructed by hierarchical classification of the fault tree structure, and the inference mechanism was given. Logical structure of the fault diagnosis in the ship lift was proposed. The implementation of the expert system for remote fault diagnosis in the ship lift was discussed, and the expert system developed was realized on the VPN virtual network. The system was applied to the Gaobaozhou ship lift project, and it ran successfully.

多种通航建筑物组合布置的通过时间研究

山区航道高水头通航建筑物多采用船闸、升船机、隧洞和中间渠道组合布置的形式。多种通航建筑物组合布置时,各通航建筑物的通过能力相互制约和影响,计算较为复杂。结合工程实际,在通过能力计算中,分析了通过各建筑物时间的匹配性及其对通航效率的影响,指出在组合布置通航建筑物时,应以船闸或升船机1次运行时间为基础,复核计算通航隧洞、辅助闸门等其他通航建筑物的1次运行时间是否小于基础时间,当大于基础时间时,应合理调整组合形式、布置形式和建设规模,成果可为类似工程提供参考。

面向船舶吊装工艺安全评估的有限元快速建模方法研究

分段吊装是船舶建造中的一项重要工艺,为精准模拟船舶吊装作业过程中眼板结构节点的应力分布,在船舶吊装有限元强度计算时眼板区域需进行细网格计算.基于由几何方法添加辅助硬点并生成过渡单元的思路,提出了一种眼板有限元细网格快速生成方法.在粗网格的基础上,将眼板几何模型进行网格细化并根据布置位置与粗网格相连接.基于HyperMesh二次开发,编制了实用可靠的程序,提高了眼板的建模计算效率.

升船机电气传动系统应急运行研究

齿轮齿条爬升式垂直升船机一般采用四点均匀驱动承船厢升降,4套驱动装置通过同步轴系统刚性连接,正常工况下四个驱动点保持同步运行,同步轴受力很小。由于承船厢重量与平衡重重量基本一致,驱动装置处于轻载状态。在保证各驱动点电机不过载和同步轴力矩不超标的条件下,本研究项目旨在论证和试验在1套电气传动装置(电机+变频器)故障退出情况下,其余3套驱动装置能否继续运行,以提高升船机运行的整体可靠性。通过理论计算,在承船厢误载水深控制在±5 cm的范围内,3台电机的出力可以驱动承船厢运行。在对电气传动系统控制架构进行调整后,实现了任意一套传动机构退出后,其余3套驱动装置继续运行的功能,并且同步轴扭矩保持在允许范围内。

欧盟航运碳减排法规对多用途重吊船队的影响

针对多用途重吊船队,按照欧盟航运碳减排法规的具体方案,使用统计的方法和数据计算,准确预算船队在欧盟排放交易体系和欧盟可持续海运燃料法规实施10年内,因船舶燃料温室气体排放带来的成本增加量。通过分析欧盟航运碳减排法规中的各种关键要素,针对多用途船型特点,给出全方面的应对方案。

增建升船机恢复海河航运功能的设想

通过对海河通航及旅游业发展现状的分析,提出在保持二道闸现有功能和结构的前提下,可考虑在此处修建升船机,打通海河下游航道,使得游船可通过二道闸,实现海河全线通航,后续可带动海河沿岸服务产业和货运运输,以此促进天津航运经济发展。

导流墩布置对岩滩升船机下游口门区通航水流条件影响

针对岩滩升船机升级改造后口门区水流紊乱,横流、回流强度超标等问题,采用二维数学模型,重点论述导流墩不同布置方式对口门区通航水流条件影响,分析导流墩不同形状、数量和相对间距下的水流流态,对比口门内横向流速、纵向流速及回流流速等水力参数,进一步探究导流墩布置规律,优化导流墩布置方式。结果表明:导流墩对口门区通航水流条件有明显改善作用,在岩滩下游口门区布置7~8个八边形导流墩,且当导流墩的间距和长度之比控制在0.50~1.00范围时,可有效改善岩滩升船机下游口门区通航流态,使其满足船舶安全通航要求。

基于改进NSGA-Ⅱ的破损沉船起吊力优化

沉船打捞工程中,按照工程经验布置的起吊力参数(位置和大小)容易使得破损沉船起吊时的内力(剪力和弯矩)较大,可能导致沉船起吊断裂,尤其当沉船存在破损时,起吊断裂的可能性大大增加。为此,从梁弯曲理论出发,针对沉船起吊时的受力特点建立了以起吊力参数为输入,以内力分布为输出的沉船内力数值计算模型;基于该计算模型,以起吊力参数为优化变量,以内力峰值为优化目标,建立了起吊力参数优化模型;采用改进的NSGA-Ⅱ算法进行优化计算。以某破损沉船为对象,通过MATLAB实现建模与优化计算,结果表明:优化后的剪力峰值下降约22.72%,弯矩峰值下降约16.13%。

升船机全生命周期BIM应用研究

目前对于通航建筑物的BIM技术应用通常局限于设计或者施工等单个阶段,缺乏对其全生命周期的BIM应用。以某升船机工程为例,将BIM技术引入其设计、施工、运维的各个阶段。在设计阶段,基于Bentley平台对升船机进行了三维模型搭建,在此基础上应用ANSYS对其进行了有限元数值仿真,应用Lumion对其进行了可视化虚拟仿真;在施工阶段,利用Microsoft Project和Synchro Pro进行了施工进度管理和施工仿真模拟;在运维阶段,借助IDEA编辑器、VSCODE软件和MySQL等软件进行代码编写,构建了基于BIM技术的智慧运维管理平台。实践表明:在升船机全生命周期中运用BIM技术,提高了设计的准确性和协同性,加强了施工的协调性,运维管理平台的搭建实现了BIM模型展示、升船机水位和状态监测等功能,为升船机运维管理提供了决策支持。研究成果可为BIM技术在类似水利工程设计、施工、运维等全生命周期的应用提供参考。

邮轮上层建筑分段吊装评估与参数敏感性分析

针对邮轮上建采用的钢板较薄,且舷侧大开孔密集,结构刚度较弱,在上建吊装过程中容易出现结构或者舾装件损伤的问题,总结邮轮上建分段吊装的评估流程,以一极地邮轮上建分段为例,开展吊装方案设计,并利用有限元对结构应力、分段整体位移与舷侧开孔局部位移进行计算评估,利用线性回归方法对吊装参数进行敏感性分析,结果表明,邮轮上建舷侧结构的局部相对位移评估十分有必要,相对于应力和整体位移,为主控因素,且垂向位移是局部位移评估的主控参量;结构应力与开孔局部位移对吊耳布置更敏感,整体位移对临时补强更敏感。

百色水利枢纽通航设施工程建设方案

百色水利枢纽最大通航水头为113.80 m,上游库区水位变幅大,下游右江水位变化速率快,航运用水会对枢纽发电效益产生影响,建设通航设施面临高水头通航、节约水资源、降低对已建设施安全与运行影响等技术难题,建设方案应实现高效通航、运行可靠、维护便利、投资经济等多重目标协同效果最优。百色水利枢纽通航设施工程采用船闸与升船机组合方案、升船机与升船机组合方案、单级升船机方案和多级船闸方案进行技术经济比选,推荐船闸与升船机组合方案,其发挥了船闸适应大水位变幅和升船机提升高度大、过闸时间短的技术优势,并对升船机形式进行比选,推荐的船闸与全平衡卷扬式垂直升船机组合方案能够实现高效通航、运行可靠等建设目标。为实现高坝通航提出了新思路,对类似工程建设及规范修编具有积极的借鉴意义。

邮轮薄板分段吊装线性与非线性分析

采用线性、材料非线性、几何非线性及双非线性方法对一典型邮轮薄板分段结构开展应力、位移的对比分析,并基于补强后的结构模型,开展线性有限元方法适用时极限舾装/结构重量比的计算。结果表明,薄板结构吊装需要考虑双非线性的影响,线性计算的得到应力和位移比双非线性大,采用线性计算的应力进行补强时会造成结构偏安全,对成本控制不利。结构的最大位移是由吊耳与分段连接处的局部刚度决定的,连接处局部刚度越弱,结构的几何非线性越明显。在吊耳与分段连接处补强足够的情况下,分段的舾装/结构重量比低于103%时,可以采用线性分析,但应力偏大约10%。

螺旋叶片对装运性能的影响与结构优化

为了解决传统薄煤层采煤机装运效率低和载荷波动大的问题,以滚筒的螺旋叶片为研究对象,通过离散元仿真试验,研究不同螺旋升角下滚筒装运性能的变化规律。结果表明:直径为1200 mm的滚筒在螺旋升角逐渐增加的情况下,滚筒的装运效率从73.31%逐步提高至76.56%,当螺旋升角达到18°时获得最佳装运效率,螺旋升角由18°继续增长至30°时,滚筒的装运效率与螺旋升角呈负相关趋势。以最佳螺旋升角为基础,对螺旋叶片进行结构优化,仿真试验表明:优化后滚筒的装运效率提高了9.94%,载荷波动降低了22.59%。

进出口大宗货物“船边直提”“抵港直装”监管机制与风险防控

为深入落实党中央、国务院优化口岸营商环境坚持稳中求进工作总基调的决策部署,张家港海关基于风险控制理念优化进出口货物“船边直提”“抵港直装”监管模式,积极探索开展扩大进出口货物“船边直提”“抵港直装”试点工作,更好服务市场主体,筑牢国门安全防线。研究表明建立“船边直提”“抵港直装”风险控制体系不仅能够提高进出口货物通关效率,同时能够防范化解重大风险。该研究为符合条件的港口推行“船边直提”“抵港直装”监管模式风险防控提供了参考。

升船机施工技术的工程实例分析与实践经验

升船机施工技术的工程实例分析与实践经验总结揭示了在某船厂2000吨级升船机项目中的关键成果。该工程充分考虑了船型、场地条件和河道条件等多方面因素,选择了卷扬式垂直升船机,展现了水域占用范围小、运行效率高、安全可靠等优势。实施过程中,通过卷扬机拉力试验、空载同步修正试验等严格的厂内试验和调试,保障了升船机的结构和性能满足要求。

景洪水力式升船机的智能安全调度运行关键技术研究与系统实现

水力式升船机是我国具有自主知识产权的新型升船机,其中调度系统安全是确保水电站长期稳定运行的关键。基于景洪电站水力式升船机的工程实践,构建了水力式升船机智能安全调度和安全管理系统,实现了智能调度申请、设备状态监测、扭矩分析监测和智能预警等功能,有效提升了水力式升船机调度运行的规范性、智能性、安全性和稳定性。