Concept of maximum discharge capacity and no-surplus flow of hydropower station and its application

Effect of Content of Mg on the Electrochemical Performance of La1-xMgxNi2.8Co0.7 (x=0.1, 0.3, 0.5) Hydrogen Storage Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.113-116.2129 ◽

2010 ◽

Vol 113-116 ◽

pp. 2129-2133

Author(s):

Jing Wang ◽

Dao Bin Mu ◽

Feng Wu ◽

Shi Chen

Keyword(s):

Hydrogen Storage ◽

Electrochemical Performance ◽

Discharge Capacity ◽

Hydrogen Storage Alloy ◽

Diffusion Method ◽

Capacity Retention ◽

Solid Diffusion ◽

Maximum Discharge

La1-xMgxNi2.8Co0.7 (x=0.1, 0.3, 0.5) hydrogen storage alloy was synthesized by solid diffusion method. The microstructure of the alloy was analyzed by XRD when the content of Mg was changed. When x equaled to 0.3, there was relative much La2Ni7 phase in the alloy and the alloy exhibited better integrated electrochemical performance. Its maximum discharge capacity reached 355.4mAh/g and capacity retention after 50 cycles（S50）was 77.80%. The results showed the existence of La2Ni7 phase would be conductive to the integrated electrochemical performance of the alloy.

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Effect of Tail Regulators on Euphrates River Flood Capacity at Al Nassiriyah City

Journal of Engineering ◽

10.31026/j.eng.2020.01.05 ◽

2019 ◽

Vol 26 (1) ◽

pp. 43-54

Author(s):

Atheer Ghazi Shayea ◽

Hayder A. Al Thamiry

Keyword(s):

Discharge Capacity ◽

Return Period ◽

River System ◽

Hydraulic Structures ◽

Euphrates River ◽

Flood Discharge ◽

Maximum Discharge ◽

River Flood ◽

River Training ◽

The Impact

Euphrates River extends about 125 km within the study area located in Annassiriyah City, Dhi Qar Governorate, Iraq. The impact of the seven hydraulic structures on the discharge capacity of the Euphrates River needs to be considered. The main objectives of this research are to increase the discharge capacity of Euphrates River within Annassiriyah City during flood seasons and study the impact of these hydraulic structures on the river capacity by using HEC-RAS 5.0.3 software. Five scenarios were simulated to study the different current condition of Euphrates River within Annassiriyah City. Other additional four scenarios were implemented through river training to increase the river capacity to 1300 m³/s; it is the flood of 100 year return period. The results of the current condition showed that the maximum discharge capacity of Euphrates River within Annassiriyah City is just 300 m³/s. The results of applied improvements show that the capacity can reach 1300 m³/s when Al Chibayish Weir was hypothetically removed from the river system. Additionally, the river capacity will be reduced to 600 m³/s when Al Chibayish Weir is considered. It was concluded that the 100-year flood discharge cannot be achieved without removing Al Chibayish Weir from the river system.

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prediction Capacity of Euphrates River at Assamawa City

Journal of Engineering ◽

10.31026/j.eng.2020.04.08 ◽

2020 ◽

Vol 26 (4) ◽

pp. 111-122

Author(s):

Hussein Shanan. A. AL-Zaidy ◽

Hayder Abdulameer. K. AL- Thamiry

Keyword(s):

Decision Maker ◽

Discharge Capacity ◽

Cross Sections ◽

Return Periods ◽

Euphrates River ◽

Real Condition ◽

The Real ◽

Flood Season ◽

Maximum Discharge ◽

The City

The reduction in the rivers capacity is one the most important issue to give the decision maker an idea during the flood season. The study area included the rivers of the Al Atshan, Al Sabeel and Euphrates, which are surveyed with a length of 21, 5 and 20 km respectively. The Euphrates , the Atshan and Al Sabeel rivers were simulated by using HEC-RAS 5.0.3 software to study the real condition within the city of Assamawa. As well as the simulation was implemented by modifying the cross sections of the Euphrates and Al Sabeel rivers to increase their capacity to 1300 and 1200 m3/s respectively which are a flood discharges100 year return periods. The results showed that the maximum discharge capacity under real conditions of Euphrates River is 750 m³/s and both Al Atshan and Al Sabeel arms are 500 m3/s.

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Influence of installation of S-shaped pipe offset on the water flow capacity of double stack drainage system in a high-rise building

Building Services Engineering Research and Technology ◽

10.1177/0143624419886096 ◽

2019 ◽

Vol 41 (5) ◽

pp. 603-622

Author(s):

Yuxi Guan ◽

Zheng Fang ◽

Jianping Yuan ◽

Zhi Tang

Keyword(s):

Discharge Capacity ◽

Pressure Fluctuation ◽

Flow Direction ◽

Drainage System ◽

Drainage Systems ◽

High Rise ◽

High Rise Building ◽

Maximum Discharge ◽

Drainage Capacity ◽

Water Seal

In high-rise and ultra-high-rise residential buildings, the drainage systems usually adopt the S-shaped offset pipe joint to avoid collisions of pipelines with beams and columns. However, the flow direction changes at the offset point would significantly affect the drainage capacity of the systems. To better understand the influence of pipe offset joints on the drainage capacity, three different building drainage systems namely YZW 1, YZW 2, and YZW 3 systems, were built up and investigated. YZW 1 system is a standard double-stack drainage system with anti-reflux H-tube joints. YZW 2 and YZW 3 systems were developed from YZW 1 by adding S-shape offset pipe joints on the 4th floor. An extra anti-reflux H-tube joint added 1 m above the offset joint as a measure for improving the drainage capacity differentiates YZW 3 system from YZW 2 system. The pressure fluctuation and water seal losses were adopted as experimental parameters to determine the maximum discharge capacity according to Standard for Capacity Test of Vertical Pipe of the Domestic Residential Drainage System. The experimental results show that the discharge capacity limitation of the drainage system with the offset joint is 6.5 L/s, which is much smaller than 11.0 L/s of the system without the offset joint. In the experiments with the offset joint, the pressure fluctuated fiercely at the position where flow direction changed and caused severe water seal losses of the floor drain and P-shaped trap. An anti-reflux H-tube joint above the original offset joint was observed to relieve the pressure fluctuation as an improvement and the drainage capacity was improved to some extent. The relationships among the maximum discharge rate, pressure fluctuation transients, and water seal losses were discussed. Lastly, a nondimensional analysis was adopted to understand the relationship between water seal losses and pressure limit values under different discharge rates for current test facilities. Practical application: A method has been tested and approved to effectively improve the discharge ability of a building drainage system that includes offset. The application of S-shape-offsets in high-rise building drainage systems can relieve the discharge congestion typically caused by standard pipe offset arrangements.

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CeO2-modified P2–Na–Co–Mn–O cathode with enhanced sodium storage characteristics

RSC Advances ◽

10.1039/c8ra04210a ◽

2018 ◽

Vol 8 (43) ◽

pp. 24143-24153 ◽

Cited By ~ 5

Author(s):

Yanzhi Wang ◽

Jiantao Tang

Keyword(s):

Discharge Capacity ◽

Cycling Stability ◽

Maximum Discharge ◽

Storage Characteristics ◽

Sodium Storage

The CeO2 modification significantly enhances the maximum discharge capacity and cycling stability of a P2–Na0.67Co0.25Mn0.75O2 cathode.

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Analysis of the Effect of Tidal Level on the Discharge Capacity of Two Urban Rivers Using Bidimensional Numerical Modelling

Proceedings ◽

10.3390/proceedings2181175 ◽

2018 ◽

Vol 2 (18) ◽

pp. 1175

Author(s):

Ignacio Fraga

Keyword(s):

Numerical Modelling ◽

Water Level ◽

Discharge Capacity ◽

River Discharge ◽

Urban River ◽

Urban Rivers ◽

Tidal Level ◽

Maximum Capacity ◽

Maximum Discharge

This article quantifies the variation of the discharge capacity of an urban river of the Galicia region due to the tidal level at the river discharge. During high tides, the water level on the river outlet produces a backwater effects that reduces the maximum discharge. This results in a decrease of the maximum capacity to one third of the maximum discharge during low tide.

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