scholarly journals Impact of hydrogen admixture on interacting premixed flames in domestic boilers

2021 ◽  
Vol 238 ◽  
pp. 04001
Author(s):  
Rachele Lamioni ◽  
Sebastiano Cinnirella ◽  
Cristiana Bronzoni ◽  
Marco Folli ◽  
Leonardo Tognotti ◽  
...  
Keyword(s):  
Natural Gas ◽  
Large Scale ◽  
Premixed Flames ◽  
Combustion Process ◽  
Efficient Operation ◽  
Gas Network ◽  
3 Dimensional ◽  
Large Scale Integration ◽  
Integration Of Renewables ◽  
Scale Integration

The injection of hydrogen into the natural gas network can contribute to the large-scale integration of renewables, as hydrogen can be easily produced through electrolysis from wind or solar energy. However, the addition of hydrogen to natural gas influences fuel properties, asking for the assessment of the safe and efficient operation of existing end-user equipment, such as domestic burners and boilers. In this work, 3-dimensional resolved numerical simulations based on Computational Fluid Dynamics are carried out to shed light on the effect of H2 addition on the combustion process occurring in condensing boilers equipped with perforated cylindrical burners. To this purpose, multi-hole geometries emulating a portion of a perforated burner are analyzed. Since the burner holes are positioned very close to each other, the interaction of the adjacent laminar premixed flames is observed to occur with influence on the flow and thermo-chemical fields which differ from those of a single premixed flame. The addition of hydrogen was found to lead to an anticipation of the reaction zone, although the general features observed with the G222 gas (23% H2, 77% CH4 ) were alike those of the G20 gas (100% CH4).

Performance and Benefit Analysis of Mining Accumulator Locomotive AC Speed System Based on DTC

2011 ◽  
Vol 328-330 ◽  
pp. 1846-1850
Author(s):  
Xi Zhang ◽  
Jie Yang ◽  
Wen Chao Chen ◽  
Qi Zhou Huang
Keyword(s):  
Large Scale ◽  
Asynchronous Motor ◽  
Speed Control ◽  
Fast Response ◽  
Efficient Operation ◽  
Ac Drive ◽  
Key Factor ◽  
Large Scale Integration ◽  
Overload Capacity ◽  
Scale Integration

The traditional mine accumulator locomotive usually takes the DC motor for its power source. And the series-wound resistance method is usually used in its speed control. With the development of power electronics technology, the AC drive system based on power electronic converters can be realized. Especially after the realization of large-scale integration and compmer controling, the performance of AC variale speed has been improved a lot. In operation, the mine accumulator locomotive not only works in frequent starting, breaking, accelerating and decelerating conditions, but also has to adapt to the bad pavement. The AC asynchronous motor has simple stmcture, sturdy and durable, and it could save power by notusing resistance when it was used in speed control. With this characteristics, the AC speed control system has the feature of fast response and high overload capacity. The AC speed system is the key factor for efficient operation of mining accumulator locomotive. Compared with the traditional DC speed system, the principle of DTC is introduced in this paper. And the advantage of operating performance and economic benefit of mining accumulator locomotive with AC speed system based on DTC is analyzed from practical application.

Multi-Flexibility Option Integration to Cope With Large-Scale Integration of Renewables

2020 ◽  
Vol 11 (1) ◽  
pp. 48-60 ◽  
Author(s):  
Marco R. M. Cruz ◽  
Desta Z. Fitiwi ◽  
Sergio F. Santos ◽  
Silvio J. P. S. Mariano ◽  
Joao P. S. Catalao
Keyword(s):  
Large Scale ◽  
Large Scale Integration ◽  
Integration Of Renewables ◽  
Scale Integration

Western Wind and Solar Integration Study Hydropower Analysis: Benefits of Hydropower in Large-Scale Integration of Renewables in the Western United States

2010 ◽  
Author(s):  
Carson M. Pete ◽  
Thomas L. Acker ◽  
Gary Jordan ◽  
David A. Harpman
Keyword(s):  
Wind Power ◽  
Large Scale ◽  
Concentrated Solar Power ◽  
Large Scale Integration ◽  
Potential Benefits ◽  
Integration Of Renewables ◽  
Scale Integration ◽  
Operational Impacts ◽  
System Operating ◽  
Solar Integration

NREL and research partner GE are conducting the Western Wind and Solar Integration Study (WWSIS) in order to provide insight into the costs and operational impacts caused by the variability and uncertainty of wind, photovoltaic, and concentrated solar power employed to serve up to 35% of the load energy in the WestConnect region (Arizona, Colorado, Nevada, New Mexico, and Wyoming). The heart of the WWSIS is an hourly cost production simulation of the balancing areas in the study footprint using GE’s Multi-Area Production Simulation Model (MAPS). The estimated 2017 load being served is 60 GW, with up to 30 GW of wind power and 4 GW of existing hydropower. Because hydropower generators are inherently flexible and often combined with reservoir storage, they play an important role in balancing load with generation. However, these hydropower facilities serve multiple higher priority functions that constrain their use for system balancing. Through a series of comparisons of the MAPS simulations, it was possible to deduce the value of hydropower as an essential balancing resource. Several case comparisons were performed demonstrating the potential benefits of hydro and to ascertain if the modeled data was within the defined hydro parameters and constraints. The results, methodologies, and conclusions of these comparisons are discussed, including how the hydro system is affected by the wind power for different wind forecasts and penetration levels, identifying the magnitude and character of change in generation pattern at each of the selected hydro facilities. Results from this study will focus on the appropriate benefits that hydropower can provide as a balancing resource including adding value to wind and solar and reducing system operating costs to nearly one billion dollars when offsetting more expensive generation systems as large penetration levels of renewable, especially wind power, are introduced to the grid system.

Plant hormones, plant growth regulators

2014 ◽  
Vol 155 (26) ◽  
pp. 1011-1018 ◽  
Author(s):  
György Végvári ◽  
Edina Vidéki
Keyword(s):  
Nervous System ◽  
Growth And Development ◽  
Large Scale ◽  
Essential Role ◽  
Higher Plants ◽  
Structure And Function ◽  
Wide Sense ◽  
Large Scale Integration ◽  
Scale Integration ◽  
And Function

Plants seem to be rather defenceless, they are unable to do motion, have no nervous system or immune system unlike animals. Besides this, plants do have hormones, though these substances are produced not in glands. In view of their complexity they lagged behind animals, however, plant organisms show large scale integration in their structure and function. In higher plants, such as in animals, the intercellular communication is fulfilled through chemical messengers. These specific compounds in plants are called phytohormones, or in a wide sense, bioregulators. Even a small quantity of these endogenous organic compounds are able to regulate the operation, growth and development of higher plants, and keep the connection between cells, tissues and synergy beween organs. Since they do not have nervous and immume systems, phytohormones play essential role in plants’ life. Orv. Hetil., 2014, 155(26), 1011–1018.

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