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China Ocean Engineering 2024年第3期38卷 467-482页

作者： shen zhong-xiang WANG Wen-qing XU Cheng-yue LUO Jia-xin LIU Ren-wei School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

In this study,a common-node DEM-SPH coupling model based on the shared node method is proposed,and a fluid–structure coupling method using the common-node discrete element method-smoothed particle hydrodynamics(DS-SPH)method is developed using LS-DYNA software.The DEM and SPH are established on the same node to create common-node DEM-SPH particles,allowing for fluid–structure interactions.Numerical simulations of various scenarios,including water entry of a rigid sphere,dam-break propagation over wet beds,impact on an ice plate floating on water and ice accumulation on offshore structures,are conducted.The interaction between DS particles and SPH fluid and the crack generation mechanism and expansion characteristics of the ice plate under the interaction of structure and fluid are also studied.The results are compared with available data to verify the proposed coupling method.Notably,the simulation results demonstrated that controlling the cutoff pressure of internal SPH particles could effectively control particle splashing during ice crushing failure.

关键词： common-node DEM-SPH fluid-structure interaction discrete element method smoothed particle hydrodynamics

Study on the Characteristics of A New Hybrid Mooring System for DualPlatform Joint Operations

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China Ocean Engineering 2023年第3期37卷 506-518页

作者： shen zhong-xiang YUAN Zhao-jun LI Hong-bin ZHU Chen-yang School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Nantong COSCO KHI Ship Engineering Co.Ltd Nantong 226005China

As the sustainable exploitation of marine resources develops,dual-platform joint operation has caught increasing attention.Dual-platform joint operation requires smaller relative motion between the two sub-platforms,which is normally difficult to be satisfied by the traditional mooring system.Therefore,a new hybrid mooring system is developed and studied in this article.To ensure safety during platform movements,both the number of anchor chains and the relative motion between the two sub-platforms are reduced in the new hybrid mooring system.By performing numerical simulations based on three-dimensional potential flow theory in AQWA and physical experiments,the performances of both the new hybrid and traditional mooring systems under two different wave conditions(i.e.,working wave and freak wave conditions) are systematically investigated.Regarding the new hybrid mooring system,the relative stability between the two sub-platforms of the new system is better,and the platforms can restore stability faster when affected by freak waves.

关键词： dual-platform joint operation platform relative stability hybrid mooring system freak wave

Numerical Simulation of Sea Ice and Structure Interaction Using Common Node DEM-SPH Model

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China Ocean Engineering 2023年第6期37卷 897-911页

作者： shen zhong-xiang WANG Wen-qing XU Cheng-yue LI Hong-bin JIANG Yin LIU Ren-wei School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

In this work,a novel fluid-structure coupling method called the common node discrete element-smoothed particle hydrodynamics(DS-SPH)method is introduced.This framework combines the principles of the common node discrete element method(DEM)and smoothed particle hydrodynamics(SPH)to construct DEM-SPH particles situated on the same node.By doing so,the DEM particles can interact with the SPH particles within their support domain,enabling fluid-structure interaction(FSI).To determine the DEM microscopic parameters required for this method,uniaxial compression and three-point bending tests are conducted on sea ice.To verify the proposed model,we select the interaction between sea ice and structures as a case study.Through simulation,the model's capability of accurately depicting sea ice deformation and fracture has been demonstrated.The results indicate that the inclusion of SPH particles with fluid properties in the DEM model has minimal impact on the main mechanical parameters of sea ice.Additionally,it helps prevent the occurrence of particle splashing during cement failure.However,it is observed that the size of DEM particles and the friction between DEM particles and the structure significantly influence the macroscopic mechanical behavior of the common-node DEM-SPH model.Finally,we compare the fracture behavior of sea ice and the ice forces acting on structures obtained from the current model with on-site measured results.The agreement between the two sets of data is excellent,further validating the effectiveness of the proposed model in practical applications.

关键词： common node DEM-SPH uniaxial compression three-point bending structure-ice interaction

Impact Analysis of Air Gap Motion with Respect to Parameters of Mooring System for Floating Platform

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China Ocean Engineering 2017年第2期31卷 141-150页

作者： shen zhong-xiang HUO Fa-li NIE Yan LIU Yin-dong Transportation Equipments and Ocean Engineering College Dalian Maritime University Dalian 116026 China School of Naval Architecture and Offshore Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China Grenland Group (China) Ltd. Shanghai 201206 China

In this paper, the impact analysis of air gap concerning the parameters of mooring system for the semi-submersible platform is conducted. It is challenging to simulate the wave, current and wind loads of a platform based on a model test simultaneously. Furthermore, the dynamic equivalence between the truncated and full-depth mooring system is still a tuff work. However, the wind and current loads can be tested accurately in wind tunnel model. Furthermore, the wave can be simulated accurately in wave tank test. The full-scale mooring system and the all environment loads can be simulated accurately by using the numerical model based on the model tests simultaneously. In this paper, the air gap response of a floating platform is calculated based on the results of tunnel test and wave tank. Meanwhile, full-scale mooring system, the wind, wave and current load can be considered simultaneously. In addition, a numerical model of the platform is tuned and validated by ANSYS AQWA according to the model test results. With the support of the tuned numerical model, seventeen simulation cases about the presented platform are considered to study the wave, wind, and current loads simultaneously. Then, the impact analysis studies of air gap motion regarding the length, elasticity, and type of the mooring line are performed in the time domain under the beam wave, head wave, and oblique wave conditions.

关键词： mooring system air gap floating platform

Numerical Simulation of Sloshing Using the MPS-FSI Method with Large Eddy Simulation

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China Ocean Engineering 2018年第3期32卷 278-287页

作者： YANG Chao ZHANG Huai-xin SU Hui-lin shen zhong-xiang State Key Laboratory of Ocean Engineering School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration(CISSE) Shanghai Jiao Tong UniversityShanghai 200240China PLA Army Engineering University Nanjing 210007China School of Naval Architecture and Ocean Engineering Dalian Maritime UniversityDalian 116026China

A numerical model has been developed to study sloshing of turbulent flow in a tank with elastic baffles. The Moving-Particle Semi-implicit method(MPS) is a kind of meshless Lagrangian calculation method. The large eddy simulation(LES) approach is employed to model the turbulence by using the Smagorinsky Sub-Particle Scale(SPS)closure model. This paper uses MPS-FSI method with LES to simulate the interaction between free surface flow and a thin elastic baffle in sloshing. Then, the numerical model is validated, and the numerical solution has good agreement with experimental data for sloshing in a tank with elastic baffles. Furthermore, under external excitations,the MPS is applied to viscous laminar flow and turbulent flow, with both the deformation of elastic baffles and the wave height of the free surface are compared with each other. Besides, the impact pressure with/without baffles and wave height of free surface are investigated and discussed in detail. Finally, preliminary simulations are carried out in the damage problem of elastic baffles, taking the advantage of the MPS-FSI method in computations of the fluid–structure interaction with large deformation.

关键词： moving particle semi-implicit method(MPS) fluid–structure interaction(FSI) large eddy simulation(LES) meshless sloshing

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基于三维激光点云的船用螺旋桨变形分析

舰船科学技术 2024年第6期46卷 26-30页

作者：牛凯梁艳沈中祥叶爱青江苏海洋大学海洋工程学院江苏连云港222005 江苏海事职业技术学院船舶与海洋工程学院江苏南京210000 江苏科技大学船舶与海洋工程学院江苏镇江210008 上海龙禹船舶技术有限公司上海200444

传统采用螺距仪的测量方式效率低且准确性有待提高,为了准确获取船用螺旋桨的变形情况,提出一种使用三维激光扫描仪对其测量并进行变形分析的方法。在获取多视角的三维激光点云数据后,先进行裁剪去噪的预处理,然后对点云进行基于改进的S... 详细信息

传统采用螺距仪的测量方式效率低且准确性有待提高,为了准确获取船用螺旋桨的变形情况,提出一种使用三维激光扫描仪对其测量并进行变形分析的方法。在获取多视角的三维激光点云数据后,先进行裁剪去噪的预处理,然后对点云进行基于改进的SAC-IA粗拼接和K-D Tree加速处理的ICP精拼接,并对拼接精度进行分析,最后在CATIA软件中对比基于点云建模拟合的模型与原设计模型,得到船用螺旋桨直观且具体的变形情况,验证了该方法的可行性。

关键词：三维激光扫描船用螺旋桨点云拼接变形

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军校青年文职教员存在的问题及对策

教育教学论坛 2024年第11期 41-44页

作者：沈湘钟代振尹美方海军士官学校兵器系安徽蚌埠233000

军队文职人员作为军队的重要组成部分,自党的十八大以来,军队面向社会招录大量文职人员,而青年文职教员在军校的教学任务中扮演重要角色,其教学水平的高低将直接影响课程教学质量。目前军校青年文职教员在任职过程中主要存在个人教学能... 详细信息

军队文职人员作为军队的重要组成部分,自党的十八大以来,军队面向社会招录大量文职人员,而青年文职教员在军校的教学任务中扮演重要角色,其教学水平的高低将直接影响课程教学质量。目前军校青年文职教员在任职过程中主要存在个人教学能力不足、专业理论和专业技能不扎实、对部队实际不了解等问题。针对青年文职教员存在的上述问题,针对性地提出三种相应对策,即提升个人教学能力、提升专业理论和专业技能、深入基层部队交流学习。

关键词：军校青年文职教员存在的问题相应对策

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同轴线-矩形波导结散射特性的数值分析

强激光与粒子束 2007年第12期19卷 2060-2064页

作者：李晓聪文光俊 shen zhong-xiang 谢康电子科技大学通信与信息工程学院RFIC研究室成都610054 School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639798 电子科技大学宽带光纤传输与通信网技术教育部重点实验室成都610054

提出了一种数值分析同轴线-矩形波导结散射特性的模式匹配方法。采用同轴线和矩形波导的本征模函数表示电磁场分量,通过同轴线-矩形波导结截面横向场分量匹配获得波导结的散射参数,引入电场模式匹配矩阵的解析形式提高了计算效率。给出... 详细信息

提出了一种数值分析同轴线-矩形波导结散射特性的模式匹配方法。采用同轴线和矩形波导的本征模函数表示电磁场分量,通过同轴线-矩形波导结截面横向场分量匹配获得波导结的散射参数,引入电场模式匹配矩阵的解析形式提高了计算效率。给出了基于模式匹配法数值仿真的各种同轴线-矩形波导结散射特性及仿真结果分析,并与3维全电磁波分析软件HFSS的仿真结果进行了比较,二者非常吻合。模式匹配法计算效率高,能广泛应用于微波毫米波元器件及系统结构的设计与优化。

关键词：微波系统波导结同轴线-矩形波导结模式匹配法散射特性

Miniaturized power detection module operating in millimeter wave band

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Journal of Electronic Science and Technology 2024年第2期22卷 69-76页

作者： xiang Zhou Zhi-Yong zhong School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real time.It is highly prospective in military and scientific research.In this paper,a broadband power detection module operating at 26.5 GHz-40.0 GHz is designed by using low-barrier Schottky diode as the detector and a comparator for threshold output.This module can dynamically detect the power range between-10 dBm and 10 dBm with the detection accuracy of 0.1 dB.Further,the temperature compensation circuit is also applied to improve the measurement error.As a result,the resulted error low to±1 dB in the temperature range of -55℃ to +85℃ is achieved.The designed module is encapsulated by a Kovar alloy with a small volume of 9 mm×6 mm×3 mm.This endows the designed module the advantages of small size,easy integration,and low cost,and even it is applicable to high-reliability environments such as satellites.

关键词： Diode Miniaturization Power detection Temperature compensation

Thermal fatigue and wear of compacted graphite iron brake discs with various thermomechanical properties

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China Foundry 2024年第3期21卷 248-256页

作者： Gui-quan Wang Zhuo Xu zhong-li Liu xiang Chen Yan-xiang Li School of Nuclear Equipment and Nuclear Engineering Yantai UniversityYantai 264005ShandongChina School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China

The increase in payload capacity of trucks has heightened the demand for cost-effective yet high performance brake discs.In this work,the thermal fatigue and wear of compacted graphite iron brake discs were investigated,aiming to provide an experimental foundation for achieving a balance between their thermal and mechanical properties.Compacted graphite iron brake discs with different tensile strengths,macrohardnesses,specific heat capacities and thermal diffusion coefficients were produced by changing the proportion and strength of ferrite.The peak temperature,pressure load and friction coefficient of compacted graphite iron brake discs were analyzed through inertia friction tests.The morphology of thermal cracks and 3D profiles of the worn surfaces were also discussed.It is found that the thermal fatigue of compacted graphite iron discs is determined by their thermal properties.A compacted graphite iron with the highest specific heat capacity and thermal diffusion coefficient exhibits optimal thermal fatigue resistance.Oxidization of the matrix at low temperatures significantly weakens the function of alloy strengthening in hindering the propagation of thermal cracks.Despite the reduced hardness,increasing the ferrite proportion can mitigate wear loss resulting from low disc temperatures and the absence of abrasive wear.

关键词： compacted graphite iron brake disc thermomechanical properties thermal fatigue wear