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Integrated lifting line/surface panel method for optimal propeller design with consideration of hub effect

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Journal of Hydrodynamics 2019年第6期31卷 1218-1230页

作者： Wen-yu Sun Guo-fu Huang China Ship scientific research Center Wuxi 214082China

An optimal marine propeller design method is proposed,which integrates the lifting line and surface panel method and is characterized by the use of the surface panel method to take the hub effect into *** developing an integrated approach instead of an iterative method for the calculation of the interaction between the hub and the designed blades,the hub effects on the optimal circulation can be accounted for throughout the theoretical design *** new integrated method provides a fast and accurate enough method to model the straight forward hub surface,in the optimal propeller design.A systematic design procedure from the basic design inputs to the blade geometry determination is performed and the designed propellers are validated by the surface panel method and the RANS *** design and analysis cases are considered by different approaches with comparison and *** a comparative study including different hub geometries is also performed to reveal the mechanism of the hub effect on the distributions of the propeller optimal loads.

关键词： Optimal circulation design lifting line method surface panel method hub effect

An integrated optimization design of a fishing ship hullform at different speeds

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Journal of Hydrodynamics 2018年第6期30卷 1174-1181页

作者： Lei Yang Sheng-zhong Li Feng Zhao Qi-jun Ni China Ship scientific research Center Wuxi 217082China

This paper shows how to improve the hydrodynamics performance of a ship by solving a shape optimization design problem at different speeds using the simulation-based design(SBD) technique. The SBD technique is implemented by integrating the advanced CFD codes, the global optimization algorithms and the geometry modification methods, which offers a new way for the hullform optimization design and the configuration innovation. The multiple speed integrated optimization for the hullform design is a challenge. In this paper, an example of the technique application for a fishing ship hullform optimization at different speeds is demonstrated. In this optimization process, the free-form deformation method is applied to automatically modify the geometry of the ship, and the multi-objective particle swarm optimization(MOPSO) algorithm is adopted for exploring the design space. Two objective functions, the total resistances at two different speeds(12 kn and 14 kn) are assessed by the RANS solvers. The optimization results show that the decrease of the total resistance is significant after the optimization at the two speeds, with a reduction of 5.0% and 11.2%, respectively. Finally, dedicated experimental validations for the design model and the optimized model are carried out for the computation and the optimization processes. At the two speeds, the reduction of the total resistance in the model scale is about 6.0% and 11.8% after the optimization. It is a valuable result in view of the small modifications allowed and the good initial performances of the original model. The given practical example demonstrates the feasibility and the superiority of the proposed SBD technique for the multiple speed integrated optimization.

关键词： Hullform design optimization simulation-based design (SBD) techniques multiple speeds optimization CFD techniques total resistance

Numerical study on the aerodynamic and hydrodynamic performances of an ultra-high-speed AAMV

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Journal of Hydrodynamics 2023年第5期35卷 980-992页

作者： Qi-jun Ni Shi-jun Ji Yi Jiang Sheng-zhong Li Yang Liu Wei-tong Xu China Ship scientific research Center Wuxi214082China

In order to investigate the resistance performance of an ultra-high-speed aerodynamically alleviated marine vehicle(AAMV),finite volume method(FVM)-based computational fluid dynamics(CFD)software STAR CCM+is used to simulate the forward motion of this *** calculated results are validated as they reach good agreement with experimental *** the motions of models with and without aero-wings,the hybrid aerodynamic and hydrodynamic mechanism of this novel hull is *** is subsequently performed that how step configuration,spray rail and deadrise angle act on hull behavior and *** results show that models with double steps and spray rail possess better resistance characteristics at high speeds,and planing surface with variable deadrise angle could further improve the overall navigation performance.

关键词： Aerodynamically alleviated effect aero-wing computational fluid dynamics(CFD) hydrodynamic performance

NUMERICAL ANALYSIS FOR CIRCULATION DISTRIBUTION OF PROPELLER BLADE

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Journal of Hydrodynamics 2010年第4期22卷 488-493页

作者： HONG Fang-wen DONG Shi-tang China Ship scientific research Center Wuxi 214082 China

A process for numerical analysis of radial circulation distribution of propeller blade is proposed and *** is based on the results of numerical simulation of the velocity field around propeller blades and in the *** well-known traditional method using tangential velocity data in the wake and applying Stockes＇s theorem was also examined in the *** results from two approaches are compared with each *** is found that if the traditional way is utilized,in many cases an unexpected ＂hump＂ appears in the circulation distribution at certain outer *** authors calculated the circulations directly around blade sections,and it is referred as direct *** unexpected hump of the circulation distribution disappears in the results of direct *** article also discusses the reasons of the appearance of the unexpected hump in traditional *** direct method is proposed to have a potential in analyzing or verifying the radial road distribution for designed propeller and the numerical analysis instead of experimental validation for circulation distribution can be as a tool in the propeller design process.

关键词： propeller blade circulation distribution load distribution

OBSERVATION AND ANALYSIS ON CHARACTERISTIC OF NATURAL RIVERS

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Journal of Hydrodynamics 2005年第5期17卷 615-620页

作者： LU Jin-you XU Hai-tao YAO Shi-ming Yangtze River scientific research Institute Wuhan 430010 China

Based on the previous study on turbulent structure, field experiments on fluctuation velocity were carried out in section Huanglingmiao of main stream of Yangtze River with a 3-D Doppler velocimeter. And a number of data such as velocity of different discharge and different vertical line were obtained. According to the field experiment data, period, frequency, period function and probability density function of large-scale coherent structure in natural river were prescribed by means of quantitative analysis. And the problem about distribution of time average velocity, turbulent intensity and Reynolds stress along depth were further analyzed and calculated. The results in this paper will deepen the understand of large-scale turbulent structure in natural river and so make the base for applying“turbulence theory” to water conservancy, hydroelectric, environment engineering and so on.

关键词： natural river large scale turbulence turbulent mechanism

Geo-spatial information and technologies in support of EU crisis management

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International Journal of Digital Earth 2010年第1期3卷 16-30页

作者： Delilah H.A.Al-Khudhairy Joint research Centre European CommissionIspra(VA)21027Italy

This paper discusses the challenges in operational crisis management and describes the role of information and geo-spatial technologies in meeting those *** paper discusses two main sources of data,Web and very high resolution(VHR)earth observation sensors,in terms of relevance to crisis management and techniques for information extraction and *** research in information text extraction and analysis is more advanced than in information image extraction and analysis,further research is required in both these fields to take advantage of the increasing complexity but richness of open source and VHR satellite *** paper also discusses the use of Web,GIS and Digital Earth technologies in facilitating collaborative work,decision-making and information sharing in crisis *** exciting and relevant advances in information sources,information extraction and analysis methods,and collaborative crisis technologies,the main challenge remains to convince stakeholders in operational crisis management that the adoption of these technologies will lead to enhanced and effective crisis management.

关键词： crisis management information extraction and analysis VHR Web geo-collaborative technologies

Leveraging ROTI map derived from Indonesian GNSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia

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Earth and Planetary Physics 2025年第1期9卷 101-116页

作者： Prayitno Abadi Ihsan N.Muafiry Teguh N.Pratama Angga Y.Putra Suraina Gatot H.Pramono Sidik T.Wibowo Febrylian F.Chabibi Umar A.Ahmad Wildan P.Tresna Asnawi research Center for Climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia School of Electrical Engineering Telkom UniversityBandungIndonesia Directorate of Laboratory Management Facilities and Science and Technology Park Indonesian National Research and Innovation Agency(BRIN)PontianakIndonesia Geophysics Laboratory Master Program in PhysicsUniversitas Gadjah Mada(UGM)YogyakartaIndonesia research Center for Space Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian Geospatial Information Agency(BIG) JakartaIndonesia research Center for Photonics Indonesian National Research and Innovation Agency(BRIN)Tangerang SelatanIndonesia Department of Earth and Planetary Sciences Hokkaido UniversitySapporoJapan

This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signals and degrade positioning *** by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude ***-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast *** provide a practical tool for EPB research,by sharing two-dimensional rate of Total Electron Content(TEC)change index(ROTI)derived from this *** generate ROTI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific *** preliminary findings from the ROTI maps of Ina-CORS are ***,the Ina-CORS ROTI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther ***,we demonstrate that combined ROTI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East *** have demonstrated the combined ROTI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,*** observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities *** sharing ROTI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionosphe

关键词： Equatorial Plasma Bubble(EPB) GNSS receivers’network Indonesia Continuously Operating Reference Station(Ina-CORS) ionospheric map Rate of TEC change index(ROTI)map

Human Effects on Tabounsou’s Coastal Ecosystem and the Matoto-Conakry Case Study of Sustainable Management Practices

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Journal of Environmental Science and Engineering(A) 2025年第1期14卷 43-52页

作者： Daouda Konate Ahmed Guisse Yamoussa Bangoura Ousmane II Camara Sekou Ahmed Bangoura Department of Fisheries and Aquaculture Higher Institute of Veterinary Sciences and Medicine of DalabaBP09 Dalaba+224Guinea Conakry Rogbanèscientific research Center BP:1516Conakry+224Republic of Guinea Boussoura National Center for Fisheries Sciences BP1515 Conakry+224Guinea

Humans have always engaged with their surroundings and the ecology in which they ***,during the industrial age,this contact has been more intense and has had a substantial impact on environment and *** example,overexploitation of natural resources,mining,pollution,and deforestation are all elements that negatively affect biodiversity and natural *** studies have been conducted to evaluate the damage caused,despite the significant uncontrolled pressure from human ***,maintaining its environment is essential to the survival of coastal ***:This study’s goal was to evaluate how human activity affected Tabounsou’s coastal ecology in order to suggest remedial actions for sustainable *** following was the methodological approach used:executive consultation and archival analysis;stakeholder survey(locals,farmers,salt producers,fishers,and loggers);inventory of species;anthropogenic activity inventory;evaluation of how human activity affects aquatic life in the research region;suggestion and action for sustainable management;Outcome:Executive consultation indicated that the main issues are:construction projects that reduce the estuary’s surface area;agricultural practices such as woodcutting and salt farming;the rise in resource exploitation;noncompliance with fisheries laws;and the catching of young ***-three percent of fisherman ditch their nets on the coast after using them,but only seventeen percent burn *** a 75%frequency rate,the same survey indicates that most fisherman fish around the *** the Tabounsou area,according to loggers’survey,68%of the wood cut is Rhizophora,24%is Avicennia,and 8%is *** fish stocks,representing nine families and nine species,were identified by the species *** 18%and 15%,respectively,the actors most frequently capture the species Pseudotolithus elongatus and Arius *** to a poll of 30 farmers,90%of them apply fertilizer to the

关键词： Coastal environment mitigation measures sustainable management.

Hydrodynamic analyses of typical underwater gliders

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Journal of Hydrodynamics 2015年第4期27卷 556-561页

作者：陈亚君陈红勋马峥 Petro China research Institute of Petroleum Exploration and Development China Ship scientific research Center

The underwater glider changes its weight and the weight distribution through the battery use, to move up and down and forward in the sea. It enjoys many advantages such as a long endurance, and a long operational range with its unique device. The performance of the underwater glider can not evaluated only by the drag, the energy consumption is also one of the key factors. In this paper, the power conversion ratio is proposed according to the transfer efficiency from the gravitational potential energy to the available work, and the performances of three typical underwater gliders are evaluated from multi-angles, such as the drag, the power conversion ratio and the barycenter＇s offset. So the glide performance and the energy consumption in various motion states can be analyzed. The results of this paper can provide a theoretical basis for further study of underwater gliders.

关键词： the underwater glider the drag the energy consumption the power conversion ratio