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An Innovative Coupled Common-Node Discrete Element Method-Smoothed Particle Hydrodynamics Model Developed with LS-DYNA and Its Applications

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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 *** DEM and SPH are established on the same node to create common-node DEM-SPH particles,allowing for fluid–structure *** 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 *** 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 *** results are compared with available data to verify the proposed coupling ***,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

Optimization of jamming formation of USV offboard active decoy clusters based on an improved PSO algorithm

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Defence Technology（防务技术） 2024年第2期32卷 529-540页

作者： Zhaodong Wu Yasong Luo Shengliang Hu college of Weapons engineering PLA Naval University of EngineeringWuhan430033China

Offboard active decoys(OADs)can effectively jam monopulse ***,for missiles approaching from a particular direction and distance,the OAD should be placed at a specific location,posing high requirements for timing and *** improve the response speed and jamming effect,a cluster of OADs based on an unmanned surface vehicle(USV)is *** formation of the cluster determines the effectiveness of ***,based on the mechanism of OAD jamming,critical conditions are identified,and a method for assessing the jamming effect is ***,for the optimization of the cluster formation,a mathematical model is built,and a multi-tribe adaptive particle swarm optimization algorithm based on mutation strategy and Metropolis criterion(3M-APSO)is ***,the formation optimization problem is solved and analyzed using the 3M-APSO algorithm under specific *** results show that the improved algorithm has a faster convergence rate and superior performance as compared to the standard Adaptive-PSO *** with a single OAD,the optimal formation of USV-OAD cluster effectively fills the blind area and maximizes the use of jamming resources.

关键词： Electronic countermeasure Offboard active decoy USV cluster Jamming formation optimization Improved PSO algorithm

Online task planning method of anti-ship missile based on rolling optimization

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Journal of Systems engineering and Electronics 2024年第3期35卷 720-731页

作者： LU Faxing DAI Qiuyang YANG Guang JIA Zhengrong college of Weaponry engineering Naval University of EngineeringWuhan 430033China

Based on the wave attack task planning method in static complex environment and the rolling optimization framework, an online task planning method in dynamic complex environment based on rolling optimization is proposed. In the process of online task planning in dynamic complex environment,online task planning is based on event triggering including target information update event, new target addition event, target failure event, weapon failure event, etc., and the methods include defense area reanalysis, parameter space update, and mission re-planning. Simulation is conducted for different events and the result shows that the index value of the attack scenario after re-planning is better than that before re-planning and according to the probability distribution of statistical simulation method, the index value distribution after re-planning is obviously in the region of high index value, and the index value gap before and after re-planning is related to the degree of posture change.

关键词： target allocation of anti-ship missile defense area rolling optimization task re-planning

赛德西港用于船舶减排的陆上可再生能源供电评估

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哈尔滨工程大学学报（英文版） 2024年第2期23卷 506-524页

作者： Merna Makram Ameen M.Bassam Adel A.Tawfik Waleed Yehia naval architecture and Marine Eng.Dept. Faculty of EngineeringPort Said UniversityPort Fuad 42526Egypt

Air pollution from shipping is becoming a critical issue,particularly in dense hub port *** proposed solution to minimize ship-based emissions at ports is the implementation of an Onshore Power Supply(OPS)*** allows ships to shut off their auxiliary engines and instead connect to the port *** there have been numerous studies conducted on ports in Europe and the United States,little research has been done on Egyptian ***,this paper aims to investigate the feasibility of implementing OPS at port Said West port in Egypt,aligning with Egypt Vision 2030’s goals for addressing climate *** research primarily focuses on analyzing data collected from calling ships to generate socio-economic and cost-effectiveness analyses of *** further enhance the environmental benefits of OPS,the paper proposes the use of solar energy as the OPS electricity *** findings of the study revealed that by relying on the national grid,emissions can be reduced by 28%.Moreover,it is predicted that this reduction could reach 100%if electricity generation is solely based on solar ***,the economic analysis demonstrates promising profitability,with a payback period of approximately two years.

关键词： Onshore power supply port sustainability Shipping emissions inventory Solar energy Photovoltaic systems

Scattering of Water Waves by Dual Symmetric Inclined Floating Porous Barriers Using the DBEM

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China Ocean engineering 2024年第1期38卷 156-168页

作者： WANG Li-xian DENG Yan-wen YE Yang-sha DENG Zheng-zhi Key Laboratory of High Performance Ship Technology(Wuhan University of Technology) Ministry of EducationWuhan 430063China School of naval architecture Ocean and Energy Power EngineeringWuhan University of TechnologyWuhan 430063China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha 410114China Institute of port Coastal and Offshore EngineeringZhejiang UniversityZhoushan 316021China

The scattering of normally incident water waves by two surface-piercing inclined perforated barriers in water with a uniform finite depth is investigated within the framework of linear water wave *** that thin barriers are zero-thickness,a novel numerical method involving the the coupling of the dual boundary element method(DBEM)with damping layers is *** order to effectively damp out the reflected waves,two damping layers,instead of pseudoboundaries are implemented near the two side boundaries of the computational ***,the modified linearized free surface boundary conditions are formulated and used for solving both the ordinary boundary integral equation as well as the hypersingular boundary integral equation for degenerate *** newly developed numerical method is validated against analytical methods using the matched eigenfunction expansion method for the special case of two vertical barriers or the inclined angle to the vertical being *** influence of the length of the two damping layers has been ***,these findings are also validated against previous results for several *** validation,the numerical results for the reflection coefficient,transmission coefficient and dissipation coefficient are obtained by varying the inclination angle and porosity-effect *** effects of both the inclination angle and the porosity on the amplitudes of wave forces acting on both the front and rear barriers are also *** is found that the effect of the inclination angle mainly shifts the location of the extremal values of the reflection and the transmission ***,a moderate value of the porosity-parameter is quite effective at dissipating wave energy and mitigating the wave loads on dual barriers.

关键词： dual boundary element method inclined perforated floating breakwater reflection coefficient transmission coefficient damping layer

Study on the mechanism of near-field underwater explosion on supported thin plates with prefabricated holes

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Acta Mechanica Sinica 2024年第8期40卷 32-44页

作者： Si Chen Jian Qin Xiangyao Meng Zhichao Lai Yanbo Wen Ruiyuan Huang School of Mechatronical engineering Beijing Institute of TechnologyBeijing100081China naval Academy Beijing100161China college of Civil engineering Fuzhou UniversityFuzhou350116China

In this study,underwater explosion tests with 2.5 g trinitrotoluene explosive under different fixed plates with prefabricated holes were *** experimental results showed that the air inflow from the prefabricated hole caused the bubble to collapse earlier with an increase in the hole *** addition,the deformation mode of the thin plate transitioned from“convex”to“concave”(up to down).Next,the coupled Eulerian-Lagrangian method was used to perform the corresponding numerical *** accuracy of the numerical simulation method was verified through a comparison with the experimental *** addition,a series of numerical simulations were conducted with different prefabricated-hole diameters,blast distances,and prefabricated-hole *** results showed that the bubble-pulsating water jet substantially influenced the deformation of the thin plate when the diameter of the prefabricated hole was within the theoretical maximum bubble *** the blast distance was within the theoretical maximum bubble radius,the thin plate was subjected to only a single bubble pulsation owing to the air inflow from the prefabricated hole.

关键词： Underwater explosion Hole High-speed camera Bubble pulsation Fixed plate

Laser-rewritable room temperature phosphorescence based on in-situ polymerized tartaric acid

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Science China Chemistry 2024年第9期67卷 3029-3038页

作者： Tuo-Yu Zhou Tai-Wen Li Hai-Fu Zhang Rui-Lin Chai Qian Zhao Penglin Zhang Guang-Yue Li Qian-Wen Wang Chang Li Yu Shu Zhi Fan Sheng-Hua Li college of Chemical engineering and Materials Science College of SciencesTianjin University of Science&TechnologyTianjin 300457China college of Chemical engineering North China University of Science and TechnologyTangshan 063210China Tianjin Key Laboratory of Multiplexed Identification for port Hazardous Chemicals Tianjin University of Science&TechnologyTianjin 300457China

Organic room temperature phosphorescence(RTP)materials have potential applications in information technology and ***,the precise control of the afterglow in reversible manners remains challenging for organic ***,we report a kind of organic RTP material fabricated by simple heating mixtures of tartaric acid(TA)and aromatic acids,which can switch their phosphorescence by *** mixtures show tunable phosphorescence from indigo to orange with phosphorescence efficiency of up to 53.99% due to locking different organic luminogens by the TA-formed matrix through the noncovalent *** afterglow of those materials lasts a few seconds and disappears by water fumigation,which can be repeated in response to wet/heat *** drop-casting those materials on glass slides,a laser-repatternable phosphorescence is achieved by facile laser direct writing and quenched by water *** results open the opportunity for the design of smart stimuli-responsive phosphorescence materials from sustainable natural products.

关键词： room temperature phosphorescence tunable afterglows tartaric acid laser direct writing stimuli-response

Study on the Load Characteristics of Submerged Body Under Internal Solitary Waves on the Continental Shelf and Slope

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China Ocean engineering 2024年第5期38卷 809-820页

作者： LIU Qian CUI Jian MEI Huan GAO Jun-liang WU Xiang-bai ZHANG Dai-yu ZHANG Rui-rui SHANG Xiao-dong School of naval architecture and Ocean engineering Jiangsu University of Science and Technology Key Laboratory of port Waterway and Sedimentation Engineering of MOT Nanjing Hydraulic Research Institute State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences Southern Marine Science and engineering Guangdong Laboratory

Based on the high-quality observation data and the numerical simulation, the evolution characteristics of internal solitary waves(ISWs) and the load on the suspend submerged body are studied on the continental shelf and slope separately. The observed ISWs exhibit the first mode depression ISWs. The amplitudes of ISWs on the shelf and slope areas reach 50 m and 80 m, respectively. The upper layer velocity in the westward direction is about 0.8 m/s on the continental shelf and 0.9 m/s on the continental slope during the passing through of ISWs. The lower layer is dominated by the eastward compensating flow. In the vertical direction, the water in front of the wave flows downward, while the water behind the wave flows upward, and the maximum vertical velocity exceeds 0.2 m/s. Numerical simulation results show that the larger the amplitude of ISWs, the larger the load on the submerged body. The force on the submerged body by ISWs is dominated by the vertical force, and the corresponding maximum vertical forces on the continental shelf and slope are-25 kN and-27 kN. The submerged body is subjected to a large counterclockwise moment and the sudden change of the moment will also cause the submerged body to capsize. This paper not only gives a deeper understanding of the characteristics of ISWs from the deep continental slope to the shallow continental shelf, but also has a certain guiding value for the prediction of ISWs and for marine military activities.

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Constructal design of a rectangular parallel phase change microchannel in a three-dimensional electronic device

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Science China(Technological Sciences) 2024年第5期67卷 1381-1390页

作者： ZHANG JiWen FENG HuiJun CHEN LinGen GE YanLin Institute of Thermal Science and Power engineering Wuhan Institute of TechnologyWuhan430205China college of Power engineering Naval University of EngineeringWuhan430033China Hubei Provincial engineering Technology Research Center of Green Chemical Equipment Wuhan430205China School of Mechanical&Electrical engineering Wuhan Institute of TechnologyWuhan430205China

Based on constructal theory,a rectangular parallel phase change microchannel model in a three-dimensional electronic device(TDED)is established with R134a as the cooling *** on the minimization of a complex function(CF)composed of linear weighting sum of maximum temperature difference and pumping power consumption,constructal design of the TDED is conducted first;and then,maximum temperature difference and pumping power consumption are minimized by non-dominated sorting genetic algorithm-II *** results reveal that there exist an optimal mass flow rate(0.0012 kg/s)and a quadratic optimal aspect ratio(AR)(0.39)of the microchannel which lead to quadratic minimum CF(0.817).Compared with the original value,the CF after optimization is reduced by 18.34%.Reducing the inlet temperature of cooling fluid and microchannel number appropriately can help to enhance the overall performance of *** using the artificial neural network and genetic algorithms in the toolboxes of Matlab software,the optimal AR gained in the Pareto solution set is located between 0.2–*** smallest deviation index among three discussed strategies is 0.346,and the corresponding optimal AR is 0.413,which is selected as the optimal design strategy of the microchannel in the TDED under multiple *** findings in this study can serve as theoretical guides for thermal designs of electronic devices.

关键词： constructal theory parallel microchannel evaporation phase change three-dimensional electronic device multi-objective optimization artificial neural network