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Numerical Study on Hydraulic Characteristics and discharge capacity of Modified Piano Key Weir with Various Inlet/Outlet Width Ratio

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World Journal of Engineering and Technology 2023年第1期11卷 113-135页

作者： Ilan Ich Genguang Zhang Anbin Li Vinhteang Kaing Ty Sok College of Water Resources and Architectural Engineering Northwest A&F University Yangling China Faculty of Hydrology and Water Resources Engineering Institute of Technology of Cambodia Russian Federation Blvd. Phnom Penh Cambodia Department of Civil and Environmental Engineering School of Environment and Society Tokyo Institute of Technology Tokyo Japan Research and Innovation Center Institute of Technology of Cambodia Russian Federation Blvd. Phnom Penh Cambodia

A modified piano key weir with a rounded nose and a parapet wall (MPKW) can improve the discharge capacity significantly compared to a standard piano key weir. However, the optimum of the inlet/outlet width ratio (Wi/Wo) on the discharge efficiency of MPKW is still not investigated numerically. The present work utilized the numerical modeling to investigate and analyze the effects of the inlet/outlet key width ratios on the hydraulic characteristics and discharge capacity of the MPKW. To validate the numerical model with the experimental data, the results indicate that the average relative error is 2.96%, which confirms that the numerical model is fairly well to predictthe specifications of flow over on the MPKW. Numerical simulation results indicated that the discharge capacity of the MPKW can be improved up to 8.5% by optimizing the Wi/Wo ratio ranging from 1.53 to 1.67 even if the other parameters of the MPKW keep unchanged. A big Wi/Wo ratio generally leads to an increase in discharge capacity at low heads and a little effect on the discharge efficiency at high heads. The discharge efficiency of the inlet and outlet crests increases up to 9.6% for high heads, while discharge efficiency of the lateral crest decreases up to 23.5% compared with the reference model. The findings of the study revealed that the intrinsic influencing mechanism of the Wi/Wo ratio on the discharge performance of MPKWs.

关键词： discharge capacity FLOW-3D Hydraulic Characteristics Numerical Simulation Modified Piano Key Weir Parameter Optimization

Experimental Study on discharge capacity of Aqueduct in the Landscape Waterfall

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Experimental Study on Discharge Capacity of Aqueduct in the ...

High-performance nickel metal hydride battery anode with enhanced durability and excellent low-temperature discharge capability

2011 International Conference on Business Management and Electronic Information(BMEI 2011)

作者： Jinan Zhou Infrastructure Management Department North China University of Water Resources and Electric Power Zhengzhou China Lingang Tian Infrastructure Management Department North China University of Water Resources and Electric Power Zhengzhou China

This study is founded on the basis of gravity similar rule,and the hydraulic model of waterfall channel in the bottom hole of Xiyagou’s spillway is *** the same time,experiments research on discharge capacity,outlet flow pattern and landscape effect of waterfall *** on examination,the discharge capacity of waterfall channel meets design *** the waterfall channel Adds air vent holes to keep the flow pattern stable.

关键词： waterfall channel model experiment discharge capacity

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Nano Research 2024年第10期17卷 8819-8825页

作者： Zhitao Chen Huitian Liu Jean Nei Nian Liu School of Chemical and Biomolecular Engineering Georgia Institute of TechnologyAtlantaGA 30332USA GP Batteries HongkongChina

Current AB_(5)-type hydrogen storage alloys employed in nickel-metal hydride(NiMH)batteries exhibit exceptional low-temperature discharge performance but suffer from limited cycle life and insufficient high-temperature *** overcome these challenges,we introduce a hydrothermal synthesized LaF_(3)coating layer on the surface of the AB_(5)anode *** LaF_(3)coating layer adds a protective barrier for the active material,significantly improving the battery's cycle life and high-temperature *** findings indicate that(1)the LaF_(3)coated anode demonstrates an extended cycle life with increased specific capacity and a capacity retention of 88%after 40 cycles of abusive overcharging and rapid discharging at room temperature.(2)The synthesized anode exhibits a 97%recovery of its specific capacity of 292.7 mAh/g following 144 h of high-temperature storage.(3)The low-temperature discharge capacity of the synthesized anode remains on par with the pristine AB_(5)alloy at 230.4 mAh/g in a-40℃*** research presents a significant advancement in hydrogen storage alloy coatings and offers valuable insights for designing electrodes in NiMH batteries.

关键词： nickel metal hydride(NiMH)batteries hydrothermal synthesis lanthanum fluoride discharge capacity low temperature

Simple electrode assembly engineering:Toward a multifunctional lead-acid battery

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Journal of Energy Chemistry 2024年第9期96卷 536-543页

作者： Xiaojuan Cao Xiaoyu Yan Kai Zhao Le Ke Xiaoyi Jiang Lingjiao Li Ning Yan Key Laboratory of Artificial Micro-and Nano-Structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan 430072HubeiChina Shenzhen Research Institute of Wuhan University Shenzhen 518057GuangdongChina

Electrochemical energy storage is a promising technology for the integration of renewable ***-acid battery is perhaps among the most successful commercialized systems ever since thanks to its excellent cost-effectiveness and safety *** of 165 years of development,the low energy density as well as the coupled power and energy density scaling restrain its wider application in real *** address this challenge,we optimized the configuration of conventional Pb-acid battery to integrate two gas diffusion *** novel device can work as a Pb-air battery using ambient air,showing a peak power density of 183 mW cm^(−2),which was comparable with other state-of-the-art metal-O_(2)*** can also behave as a fuel cell,simultaneously converting H_(2)and air into electricity with a peak power density of 75 mW cm^(−2).Importantly,this device showed little performance degradation after 35 h of the longevity *** work shows the exciting potential of lead battery technology and demonstrates the importance of battery architecture optimization toward improved energy storage capacity.

关键词： Lead-acid battery Decoupled electrode reaction Energy storage discharge capacity Fuel cell

Accurate estimation of Li/Ni mixing degree of lithium nickel oxide cathode materials

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Chinese Physics B 2024年第5期33卷 631-635页

作者：陈鹏浩徐磊禹习谦李泓 Institute of Physics Chinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Beijing Frontier Research Center on Clean Energy Huairou DivisionInstitute of PhysicsChinese Academy of SciencesBeijing 101400China

Li/Ni mixing negatively influences the discharge capacity of lithium nickel oxide and high-nickel ternary cathode ***,accurately measuring the Li/Ni mixing degree is difficult due to the preferred orientation of labbased XRD measurements using Bragg–Brentano ***,we find that employing spherical harmonics in Rietveld refinement to eliminate the preferred orientation can significantly decrease the measurement error of the Li/Ni mixing *** Li/Ni mixing ratio obtained from Rietveld refinement with spherical harmonics shows a strong correlation with discharge capacity,which means the electrochemical capacity of lithium nickel oxide and high-nickel ternary cathode can be estimated by the Li/Ni mixing *** findings provide a simple and accurate method to estimate the Li/Ni mixing degree,which is valuable to the structural analysis and screening of the synthesis conditions of lithium nickel oxide and high-nickel ternary cathode materials.

关键词： lithium nickel oxide high-nickel ternary cathode Li/Ni mixing spherical harmonics function discharge capacity

Study on High Rate discharge Performance and Mechanism of AB_5 Type Hydrogen Storage Alloys

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Journal of Rare Earths 2004年第4期22卷 509-513页

作者：郭靖洪陈德敏于军张建海刘国忠杨柯 Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China Suppo Battery Co. Ltd. Shenyang 110015 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China Suppo Battery Co. Ltd. Shenyang 110015 China

The effects of surface treatment, particle size distribution,rare earth composition and B additive on the high rate discharge performance of hydrogen storage alloys were investigated. It is found that the activity, discharge capacity and high rate dischargeability of the alloys are improved after physical and chemical modification as a result of the increase of the surface area and formation of the electrocatalysis layers, which increase both the electrochemical reaction rate on the alloy surface and H diffusion rate in the alloy bulk. It is also found that both the over-coarse and over-fine particle size increase the contact resistance of the electrode, resulting in a decrease of discharge capacity, deterioration of high rate dischargeability and lower discharge plateau. In another word, a suitable particle size distribution can enhance the alloy activity, discharge capacity and high rate dischargeability. In addition, the high rate dischargeability is enhanced by increasing La content and decreasing Ce content of the alloy composition because of enlargement of the unit cell volume and the improvement of the surface activity. Moreover, B additive resultes in the formation of the second phase, and makes the alloys easier pulverization, which greatly improves the activity, discharge capacity and high rate dischargeability.

关键词： storage energy technology hydrogen storage alloy discharge capacity activity high rate dischargeability rare earths

Research on characteristics of acoustic signal of typical partial discharge models

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Global Energy Interconnection 2022年第1期5卷 118-130页

作者： Hang Ji Xing Lei Qiang Xu Chengjun Huang Ting Ye Shangqing Yuan State Grid Shanghai Municipal Electric Power Company Shanghai 200122P.R.China Power Monitoring and Diagnostic Technology Ltd. San Jose CA 95119USA

The pulse current method,acoustic and ultrasonic partial discharge(PD)detection,and voiceprint PD detection are commonly used detection methods for the PD detection of power *** study the characteristics of PD signals of typical discharge models based on the principles of the above three detection methods,an acoustic detection experimental system consisting of a needle-tip model and a surface model was *** tests were carried out on needle-tip models with different curvature radii and surface discharge models with different lengths of conductive *** experimental results showed that acoustic and ultrasonic PD detection and voiceprint PD detection exhibited different sensitivities to the needle-tip discharge models,and the combination of acoustic and ultrasonic PD and voiceprint PD detection was more beneficial for the comprehensive detection of cable PD *** on voiceprint recognition technology,this study drew FFT(Fast Fourier Transformation)diagrams of different types of PD acoustic signals and analyzed the differences in the ultrasonic signal frequency *** frequency band of the voiceprint PD signal of the needle-tip discharge models was concentrated in the range 17-27 kHz,and the frequency band of the voiceprint PD signal of the conductive paste discharge models was concentrated in the range 20-25 *** measurement of voiceprint PD signals in these frequency bands were strengthened when the PD of a cable was detected on-site,which provides the basis for the use of the cable model for on-site PD detection.

关键词： Needle-tip model Radius of curvature Surface model discharge capacity Number of pulses

Effect of Al substitution on phase evolution in synthesized Mg_(2)Cu nanoparticles

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International Journal of Minerals,Metallurgy and Materials 2023年第1期30卷 63-71页

作者： Elham Mohseni-Sohi Farshid Kashani Bozorg School of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehranPO Box 11155/4563Iran

The effect of Mg replacement with Al on the discharge capacity of Mg_(2)Cu powder mixture was *** mixture of nano-crystalline powder was prepared via mechanical alloying(MA)technique with a high energy planetary ball *** addition,different moles of Al(0.05,0.1,0.15,0.2,and 0.3 M)were substituted to Mg_(2)Cu powder.X-ray diffraction(XRD),scanning electron microscopy(SEM),and transmission electron microscopy(TEM)were used to analyze changes in structure,morphology,and grain *** obtained powder was utilized as an anode in a nickel-metal hydride battery(Ni-MH).In the specimens with 0.05 M Al content,the orthorhombic structure of Mg_(2)Cu is emerged after 5 h *** results reveal that more than 0.1 M Al substitution leads to an appearance of MgCu_(2) *** substi-tution does not affect microstructure uniformity;however,it causes a decrease in crystalline size and lattice *** selected area diffraction(SAD)pattern elucidates that the electrode with the Mg_(1.9)Al_(0.1)Cu chemical composition and 20 h milling has the maximum discharge capacity.

关键词： Mg_(2)Cu mechanical alloying nanocrystalline discharge capacity

Hydrogen storage behavior of nanocrystalline and amorphous La-Mg-Ni-based LaMg_(12)-type alloys synthesized by mechanical milling

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Transactions of Nonferrous Metals Society of China 2017年第3期27卷 551-561页

作者： Yang-huan ZHANG Long-wen LI Dian-chen FENG Peng-fei GONG Hong-wei SHANG Shi-hai GUO Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-metal Resources Inner Mongolia University of Science and Technology Baotou 014010 China Department of Functional Material Research Central Iron and Steel Research Institute Beijing 100081 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Nanocrystalline and amorphous LaMg11Ni+x%Ni(x=100,200,mass fraction)alloys were synthesized by *** electrochemical hydrogen storage properties of the as-milled alloys were tested by an automatic galvanostatic *** gaseous hydrogen absorption and desorption properties were investigated by Sievert’s apparatus and differential scanningcalorimeter(DSC)connected with a *** results indicated that increasing Ni content significantly improves the gaseousand electrochemical hydrogen storage performances of the as-milled *** gaseous hydrogen absorption capacities andabsorption rates of the as-milled alloys have the maximum values with the variation of the milling *** the hydrogen desorptionkinetics of the alloys always increases with the extending of milling *** addition,the electrochemical discharge capacity andhigh rate discharge(HRD)ability of the as-milled alloys both increase first and then decrease with milling time prolonging.

关键词： Ni-MH battery hydrogen storage alloy mechanical milling discharge capacity kinetics