检索结果-南通市图书馆

Cavitating Flow over a Mini Hydrofoil

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2012年第1期29卷 198-201页

作者： luo xian-wu JI Bin ZHANG Yao XU Hong-Yuan State Key Laboratory for Hydroscience and Engineering Tsinghua UniversityBeijing 100084 China Ship Development and Design Center Wuhan 430064

We consider a cavitating flow over a mini hydrofoil (foil profile:Clark-Y-11.7) having a 14mm chord length in a cavitation tunnel at various cavitation *** observations show that cavitating flows over a miniature hydrofoil display several types of cavitation behavior,such as cavitation inception,sheet cavitation,cloud cavitation and super cavitation with the decreasing cavitation *** the same cavitation conditions,cavitation over a mini hydrofoil would be suppressed in comparison to cavitation over an ordinary *** cavitation scale effect is suspected to be caused by the Reynolds number.

关键词： number cavitation ordinary

NUMERICAL INVESTIGATION OF THE VENTILATED CAVITATING FLOW AROUND AN UNDER-WATER VEHICLE BASED ON A THREE-COMPONENT CAVITATION MODEL

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2010年第6期22卷 753-759页

作者： JI Bin luo xian-wu PENG Xiao-xing ZHANG Yao wu Yu-lin XU Hong-yuan State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China China Ship Scientific Research Center Wuxi 214082 China State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

Based on the Reynolds-Averaged Navier-Stokes equations and mass transfer model, an approach, where a three-component cavitation model is proposed, is presented to simulate ventilated cavitating flow as well as natural cavitation. In the proposed cavitation model, the initial content of nucleus in the local flow field is updated instantaneously, and is coupled with the Rayleigh-Plesset equation to capture the cavity development. The proposed model is applied to simulate the cavitating flow around an under-water vehicle in different cavitation conditions. The results indicate that for the natural and ventilated cavitation simulation, the predicted cavitation characteristics including the cavity length, cavity diameter and cavity shape agree satisfactorily with the analytic and experimental results, for the ventilated cavitation, the proposed methods reproduce the special behavior that the axial line of the cavity bends and rises at the tail part. The study concludes that the ventilated flow rate of the non-condensate gas influences the development of natural cavitation as well as ventilated cavitation, and the vapor cavity is suppressed remarkably by the gas cavity with the increase of the gas ventilation.

关键词： under-water vehicle natural cavitation ventilated cavitation three-component model

Investigation on cavitating turbulent flow for the twisted NACA66 hydrofoil using a PANS model with helicity modification

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2024年第2期36卷 219-231页

作者： Chen Geng Zhao-hui Qian Ke-xin Zheng Wei-xiang Ye xian-wu luo State Key Laboratory of Hydroscience cand Engineering Deparment of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China

In the present paper,the unsteady cavitating turbulent flow over the twisted NACA66 hydrofoil is investigated based on an modified shear stress transfer k-ωpartially averaged Navier-Stokes(MSST PANS)model,i.e.,new MSST PANS(NMSST PANS)model,where the production term of kinetic energy in the turbulence model is modified with *** with the experimental data,cavitation evolution and its characteristic frequency are satisfactorily predicted by the proposed NMSST PANS *** is revealed that the interaction among the main flow,the reentrant jets,and sheet cavitation causes the formation of the primary shedding cavity near the mid-span and the secondary shedding cavity at each side of the twisted hydrofoil,and further induces the remarkable pressure gradient around shedding *** with the development of the primary and the secondary shedding cavities,the great pressure gradient associated with large cavity volume variation promotes the vortical flow generation and the spatial deformation of vortex structure during cavitation evolution,and results in the primary and the secondary U-type ***,dynamic mode decomposition(DMD)analysis is utilized to confirm the interaction among the main flow,the main reentrant jet and two side reentrant jets,and *** results indicate that the proposed NMSST PANS model is suitable to simulate the complicated cavitating turbulent flow for various engineering applications.

关键词： Cavitating turbulent flow partially averaged Navier-Stokes(PANS)model hydrofoil numerical simulation

Theoretical Design of Defects as a Driving Force for Ion Transport in Li_(3)OBr Solid Electrolyte

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy & Environmental Materials 2024年第3期7卷 143-153页

作者： Xingyun luo Yanlu Li xian Zhao State Key Lab of Crystal Materials and Institute of Crystal Materials Shandong UniversityJinan 250100China Center for Optics Research and Engineering Shandong UniversityQingdao 266237China

Due to ever-increasing concerns about safety issues in using Li ionic batteries,solid electrolytes have extensively *** Li-rich antiperovskite Li_(3)OBr has been considered as a promising solid electrolyte candidate,but it still suffers challenges to achieve a high ionic conductivity owing to the high intrinsic symmetry of the crystal ***,we presented a design strategy that introduces various point defects and grain boundaries to break the high lattice symmetry of Li_(3)OBr crystal,and their effect and microscopic mechanism of promoting the migration of Li-ion were explored *** has been found that Li_(i)are the dominant defects responsible for the fast Li-ion diffusion in bulk Li_(3)OBr and its surface,but they are easily trapped by the grain boundaries,leading to the annihilating of the Frenkel defect pair V'_(Li)+Li_(i),and thus limits the V'_(Li)diffusion at the grain *** V_(Br)defect near the grain boundaries can effectively drive V'_(Li)across the grain boundary,thereby converting the carrier of Li^(+)migration from Li,in the bulk and surface to V'_(Li)at the grain boundary,and thus improving the ionic conductivity in the whole Li_(3)OBr *** work provides a comprehensive insight into the Li^(+)transport and conduction mechanism in the Li_(3)OBr *** opens a new way of improving the conductivity for all-solid-state Li electrolyte material through the defect design.

关键词： defects density functional theory ionic migration solid electrolyte

Efficient removal of U(VI) from wastewater by a sponge-like 3D porous architecture with hybrid electrospun nanofibers

在线全文

学校读者我要写书评

暂无评论

Water Science and Engineering 2024年第2期17卷 150-156页

作者： Lin Hu Lin Chen xian-kun wu Rui luo Rong-guan Lv Zheng-hao Fei Feng Yang School of Chemistry and Environmental Engineering Yancheng Teachers UniversityYancheng 224051China Jiangsu Province Engineering Research Center of Agriculural Breeding Pollution Control and Resource Yancheng 224051China Jiangsu Nanda Huaxing Science and Technology of Environmental Protection Co.Ltd. Yancheng 224001China

Removal of uranium(VI)from nuclear wastewater is urgent due to the global nuclear energy *** study synthesized novel sponge-like 3D porous materials for enhanced uranium adsorption by combining electrospinning and fibrous freeze-shaping *** materials possessed an organic-inorganic hybrid architecture based on the electrospun fibers of polyacrylonitrile(PAN)and SiO_(2).As a sup-porting material,the surface of fibrous SiO_(2) could be further functionalized by cyano groups via(3-cyanopropyl)*** the cyano groups were turned into amidoxime(AO)groups to obtain a amidoxime-functionalized sponge(PAO/SiO_(2)-AO)through the subsequent ami-doximation *** proposed sponge exhibited enhanced uranium adsorption performance with a high removal capacity of 367.12 mg/g,a large adsorption coefficient of 4.0×10^(4)mL/g,and a high removal efficiency of 97.59%.The UO_(2)^(2+)adsorption kinetics perfectly conformed to the pseudo-second-order *** sorbent also exhibited an excellent selectivity for UO_(2)^(2+) with other interfering metal ions.2023 Hohai *** and hosting by Elsevier B.V.

关键词： Uranium removal Sponge Amidoximation Organic-inorganic hybrid structure Electrospinning

Implicit large eddy simulation of unsteady cloud cavitation around a plane-convex hydrofoil

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2015年第6期27卷 815-823页

作者： HIDALGO Victor 罗先武 ESCALER Xavier 季斌 AGUINAGA Alvaro Beijing Key Laboratory of CO2 Utilization and Reduction Technology Tsinghua University CDIF Universitat Politècnica de Catalunya School of Power and Mechanical Engineering Wuhan University Mechanical Engineering Department Escuela Politecnica Nacional University

The present paper focuses on the erosive cavitation behavior around a plane convex hydrofoil. The Zwart-Gerber-Belamri cavitation model is implemented in a library form to be used with the OpenFOAM. The implicit large eddy simulation （ILES） is app- lied to analyze the three-dimensional unsteady cavitating flow around a plane convex hydrofoil. The numerical results in the cases under the hydrodynamic conditions, which were experimentally tested at the high speed cavitation tunnel of the l^cole Polytechnique F6d＆ale de Lausanne （EPFL）, clearly show the sheet cavitation development, the shedding and the collapse of vapor clouds. It is noted that the cavitation evolutions including the maximum vapor length, the detachment and the oscillation frequency, are captured fairly well. Furthermore, the pressure pulses due to the cavitation development as well as the complex vortex structures are reasona- bly well predicted. Consequently, it may be concluded that the present numerical method can be used to investigate the unsteady cavitation around hydrofoils with a satisfactory accuracy.

关键词： implicit large eddy simulation (ILES) unsteady partial cavitation Zwart-Gerber-Belamri cavitation model OpenFOAM,Q - criterion

Vulnerability and Conservation of Nearshore Cetaceans to Increasing Vessel Traffic:The Indo-Pacific Humpback Dolphin in the South China Sea

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2024年第4期23卷 1003-1014页

作者： luo Dingyu GUO Lang HUANG Nuoyan WANG Hongri ZENG Chen TANG Xikai XU Zhuo wu Yuping SUN xian School of Marine Sciences Zhuhai Key Laboratory of Marine Bioresources and EnvironmentGuangdong Provincial Key Laboratory of Marine Resources and Coastal EngineeringPearl River Estuary Marine Ecosystem Research Sta-tionMinistry of EducationSun Yat-Sen UniversitySouthern Marine Science and Engineering Guangdong Labora-tory(Zhuhai)Zhuhai 519082China

A comprehensive risk assessment to evaluate the vulnerability of the nearshore cetaceans to increasing marine traffic is *** this study,the risk to Indo-Pacific humpback dolphins(Sousa chinensis)in the main habitats in China was assessed based on a semiquantitative spatial vulnerability analysis.85%of the(sub)population which overlapped with the lanes of ferries and/or cargo vessels,with exposure scores of 1.23±0.31(calculated based on the proportion of sea routes that overlap the dolphin’s range).A combination of high exposure to the sea routes and sensitivity to marine traffic would render the(sub)populations to be highly vulnerable(EPRE:5.21 and XM:4.47).A low frequency of vessels and an awareness of the ecology assures a low vulnerability(SH:2.43,EZ:2.73).Uncertainty scores were commonly lower for the higher vulnerable populations,and higher for the lower vulnerable populations,suggesting additional field data and more monitoring are *** years of field data have been used to analyze the influences of various types of marine traffic on humpback dolphin *** and non-fishing vessels were significantly different(χ^(2)=65.19,p<0.01).The humpback dolphins were attracted by fishing vessels(83.1%)but avoided non-fishing vessels(95.2%).We recommend a management with seasonal and geographical constraints,to balance economic development and environmental conservation.

关键词： Indo-Pacific humpback dolphin vessel impacts risk analysis protection strategy

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

在线全文

学校读者我要写书评

暂无评论

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

Nanomedicine Disrupts Stromal Barriers to Augment Drug Penetration for Improved Cancer Therapy

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第10期42卷 1175-1189页

作者： Guo-Feng luo Wei-Hai Chen xian-Zheng Zhang state Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei KeyLaboratory of StomatologySchool&Hospital of StomatologyWuhan UniversityWuhanHubei 430079China Key Laboratoryof Biomedical Polymers of Ministry of Education&Departmentof Chemistry Wuhan UniversityWuhanHubei 430072China

Tumor stroma composing diverse extracellular matrixes(ECM)and stromal cells shapes a condensed physical barrier,which severely hampers the efficient accessibility of nanomedicine to tumor cells,especially these deep-seated in the core of *** barrier significantly compromises the antitumor effects of drug-loaded nanomedicine,revealing the remarkable importance of disrupting stromal barrier for improved tumor therapy with deep penetration *** achieve this goal,various nanoparticle-based strategies have been developed,including direct depleting ECM components via delivering anti-fibrotic agents or targeting stromal cells to suppress ECM expression,dynamic regulation of nanoparticles’physicochemical properties(i.e.,size,surface charge,and morphology),mechanical force-driven deep penetration,natural/biomimetic self-driven nanomedicine,and transcytosis-inducing *** these nanostrategies were systemically summarized in this review,and the design principles for obtaining admirable nanomedicine were *** the rapid development of nanotechnology,elaborate design of multifunctional nanomedicine provides new opportunities for overcoming the critical stromal barriers to maximize the therapeutic index of various therapies,such as chemotherapy,photodynamic therapy,and immunotherapy.

关键词： Nanomedicine Tumor stroma Deep penetration Enhanced drug perfusion Cancer therapy Drug carriers Biomaterials Nanotechnology