Analysis of a Large Scale Liquid Hydrogen Dispersion Using the Multi-Phase Hydrodynamics Analysis Code (CHAMPAGNE)

2002 ◽  
Vol 124 (4) ◽  
pp. 283-289 ◽  
Author(s):  
K. Chitose ◽  
M. Okamoto ◽  
K. Takeno ◽  
K. Hayashi ◽  
M. Hishida
Keyword(s):  
Large Scale ◽  
Clean Energy ◽  
Liquid Hydrogen ◽  
Calculation Model ◽  
Small Scale ◽  
Simulation Code ◽  
Large Tank ◽  
Basic Functions ◽  
Multi Phase ◽  
And Storage

It is planned to use hydrogen extensively as a source of clean energy in the new century. As part of our investigation for an International Clean Energy Network Using Hydrogen Conversion (WE-NET), we have been studying to establish a safety scheme to ensure that both existing and new hydrogen technologies are implemented without endangering public safety. In this plan, we consider the transport and storage of a large quantity of hydrogen in a large tank. First we must evaluate the consequence of the postulated accident of liquid hydrogen. Since we have developed the multi-phase hydrodynamics analysis code (CHAMPAGNE), we apply the code to simulate the formation and dispersion of hydrogen vapor clouds. In the present paper we have improved the calculation model in two ways. We added a function to CHAMPAGNE for solving evaporation phenomena realistically, made many parametric calculations and planned the small-scale hydrogen dispersion experiments for the validation of this model. Another improvement is the turbulent mixing of evaporated liquid hydrogen. Now we have completed the basic functions of our simulation code. And these models of CHAMPANGE code must be verified by the experimental data.

Analysis of a Large Scale Liquid Hydrogen Dispersion Using the Multi-Phase Hydrodynamics Analysis Code (CHAMPAGNE)

1999 ◽  
Author(s):  
K. Chitose ◽  
K. Takeno ◽  
M. Okamoto ◽  
K. Hayashi ◽  
M. Hishida
Keyword(s):  
Large Scale ◽  
Clean Energy ◽  
Liquid Hydrogen ◽  
Calculation Model ◽  
Small Scale ◽  
Simulation Code ◽  
Large Tank ◽  
Basic Functions ◽  
Multi Phase ◽  
And Storage

Abstract It is planned to use hydrogen extensively as a source of clean energy in the next century. As part of our investigation for an International Clean Energy Network Using Hydrogen Conversion (WE-NET), we have been studying to establish a safety scheme to ensure that both existing and new hydrogen technologies are implemented without endangering public safety. In this plan, we consider the transport and storage of a large quantity of hydrogen in a large tank. First we must evaluate the consequence of the postulated accident of liquid hydrogen. Since we have developed the multi-phase hydrodynamics analysis code (CHAMPAGNE), we apply the code to simulate the formation and dispersion of hydrogen vapor clouds. In the present paper we have improved the calculation model in two ways. We added a function to CHAMPANGE for solving evaporation phenomena realistically, made many parametric calculations and planned the small-scale hydrogen dispersion experiments for the validation of this model. Another improvement is the turbulent mixing of evaporated liquid hydrogen. Now we have completed the basic functions of our simulation code. And these models of CHAMPANGE code must be verified by the experimental data.

scholarly journals Zero boil-off methods for large-scale liquid hydrogen tanks using integrated refrigeration and storage

2017 ◽  
Vol 278 ◽  
pp. 012012
Author(s):  
W U Notardonato ◽  
A M Swanger ◽  
J E Fesmire ◽  
K M Jumper ◽  
W L Johnson ◽  
...  
Keyword(s):  
Large Scale ◽  
Liquid Hydrogen ◽  
And Storage

scholarly journals Optimized design and simulation of a hybrid storage system based on hydrogen as an energy carrier

2022 ◽  
Vol 334 ◽  
pp. 03002
Author(s):  
Maria Alessandra Ancona ◽  
Michele Bianchi ◽  
Lisa Branchini ◽  
Francesco Catena ◽  
Andrea De Pascale ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Renewable Energy Sources ◽  
Storage System ◽  
Energy System ◽  
Calculation Model ◽  
Small Scale ◽  
Optimized Design ◽  
Low Carbon ◽  
Low Carbon Economy ◽  
And Storage

The integration of renewable energy sources into the electricity system can contribute to the development of a low-carbon economy. However, due to the intermittency and non-programmability of these sources, problems related to the management of local electricity grids may occur. A possible solution or limitation to these issues is given by the electrical storage. In addition, in the next future, domestic micro-grids are expected to play a fundamental role in electric power networks, driving both the academic and industrial research interests in developing highly efficient and reliable conversion and storage technologies. In this study, the behavior of a small-scale hybrid energy system for hydrogen production and storage has been predicted, by means of a developed calculation model, and the operational strategy of the system has been optimized with the aim to maximize the hydrogen production. In addition, with the aim to maximize the overall solar-to-hydrogen chain efficiency, the whole system model has been applied to different operating scenarios, to identify the optimal management strategy to control it.

scholarly journals Geo-Spatially Based Analysis And Economic Feasiblity Evaluation Of Waste-To-Energy Facilities: A Case Study Of Local Government Areas Of Anambra State Of Nigeria

2021 ◽  
Author(s):  
Emmanuel Chukwuma ◽  
John Ojediran ◽  
Daniel Azikiwe Anizoba ◽  
Joseph Azikiwe Ubah ◽  
Pius Nwachukwu
Keyword(s):  
Local Government ◽  
Large Scale ◽  
Clean Energy ◽  
Economic Feasibility ◽  
Waste To Energy ◽  
Small Scale ◽  
Optimum Number ◽  
Organic Fraction ◽  
Anambra State

Abstract Access to affordable clean energy source as stipulated in UN SDG goal number 7 is important for the development and socio-economic well-being of people, the need for proper assessment of resources to achieve this goal is indisputable. The goal of this study is to assess the economic feasibility of utilizing organic fraction of Municipal Solid Wastes (MSWof) using a case study of 21 Local Government Areas (LGA) or Authority for Anambra State of Nigeria for waste to energy project. The quantity of organic fraction of MSW, energy recovery and optimum number of plants at the various LGAs was estimated. The result of the study indicates that about 198 tons maximum value of MSWof can be generated daily in Aguata LGA, with electric energy potential value of 545MW. The number of plants for the LGAs ranged from 10 to 50 and from 3 to 12 for small and medium scale plants. A large scale plant of about 50m3 can possibly be installed at all the LGAs, with a maximum of 4 plants in Idemili and Aguata LGA. The economic assessment based on Net Present Value (NPV) criteria shows poor economic feasibility for small scale plant, while NPV was positive for medium and large scale plants. The Internal Rate of Return (IRR) ranged from 0.32 to 0.94, with a general increase from small scale to large scale economic feasibility. It is suggested that the autonomy of the various LGAs in the country should serve as a major motivation in adopting bio-energy projects independently, and this study will serve as a decision toolkit in the appropriate scale to be adopted.

scholarly journals Towards a Clean and Sustainable Distributed Energy: The Potential of Integrated PEMFC-CHP

2014 ◽  
Vol 7 (1) ◽  
Keyword(s):  
Fuel Cell ◽  
Co2 Emissions ◽  
Carbon Capture ◽  
Cold Plasma ◽  
Carbon Capture And Storage ◽  
Plasma Jet ◽  
Water Electrolysis ◽  
Clean Energy ◽  
Small Scale ◽  
And Storage

The use of fossil fuels within the current infrastructure for domestic energy supply is one of the main causes of anthropogenic emissions. The mitigation options to meet the ambitious carbon reduction targets set by the UK government are discussed in this paper, including the use of carbon capture and storage technology, clean renewable energy integration and a proposed system of integrated fuel cell combined heat and power (FC-CHP) technology. Analysis shows that the use of carbon capture and storage (CCS) technology within the current infrastructure can abate half the electricity associated CO2 emissions; however, this comes at a high cost penalty. The emissions associated with domestic heat cannot be prevented without changes in the energy infrastructure. Hydrogen powered fuel cells can provide clean energy at a range of scales and high efficiencies, especially when employed with a CHP system. However, production of CO2 free hydrogen is essential for fuel cell technology to contribute substantially to a low carbon economy globally. In this work three methods were investigated for small scale distributed hydrogen production, namely steam methane reforming, water electrolysis and cold plasma jet. The criteria used for comparisons include the associated CO2 emissions and the cost of energy production. Cold plasma jet decomposition of methane shows a high potential when combined with integrated FC-CHP technology for economically viable and CO2 free generation of energy, especially in comparison to water electrolysis. Including the value of the solid carbon product makes the plasma system most attractive economically.

scholarly journals Piezoeletricity as an Alternative Source of Electric Power Generation in an Education Institution in the Amazon

2019 ◽  
Vol 7 (11) ◽  
pp. 467-474
Author(s):  
Yasmin Souza de Carvalho ◽  
Elizeu Moraes da Silva ◽  
Fabiana Rocha Pinto ◽  
David Barbosa de Alencar ◽  
Igor Felipe Oliveira Bezerra
Keyword(s):  
Energy Production ◽  
Large Scale ◽  
New Technology ◽  
Education Institution ◽  
Clean Energy ◽  
Piezoelectric Ceramics ◽  
Production Model ◽  
Small Scale ◽  
Alternative Source ◽  
Short Time

The development of technologies for the generation of clean and sustainable energy has brought significant changes to the energy sector in Brazil and worldwide. The newest technology is piezoelectricity, which although it has been studied for years, has not yet gained its proper space in the national and international electrical matrices. With this in mind, the present work aims to describe the process of installing a prototype carpet using piezoelectric ceramics that, through a force applied by any individual, is capable of generating enough energy for the operation of a turnstile in a HEI from Manaus-AM. The application was tested by modeling applying mathematical equations in the working of the prototype developed by APC International. Different answers were obtained considering the different dimensions for the piezoelectric parts. However, it is understood that this energy production model, treated as a new technology, presents economic viability in its implementation. One of the results demonstrates that the smaller the ceramic piece, the greater the energy production and can be adapted over time to respond to large productions. Thus, it is concluded from the calculations made that piezoelectric ceramics is an excellent alternative for the production of clean energy on a small scale, in a short time, and in the long term can reach large scale.

scholarly journals An Income Distributing Optimization Model for Cooperative Operation among Different Types of Power Sellers Considering Different Scenarios

Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2895 ◽  
Author(s):  
Shenbo Yang ◽  
Zhongfu Tan ◽  
Liwei Ju ◽  
Hongyu Lin ◽  
Gejirifu De ◽  
...  
Keyword(s):  
Income Distribution ◽  
Optimization Model ◽  
Large Scale ◽  
Supply And Demand ◽  
Thermal Power ◽  
Clean Energy ◽  
Northern China ◽  
Operating Mode ◽  
Calculation Model ◽  
Net Income

To alleviate the shortcomings of large-scale grid connections for clean energy, which require stable thermoelectric units to provide backup services, a stable cooperative alliance among different energy types of power sellers must be established. Consequently, a reasonable method to distribute income is required, due to different contributions of each entity in the alliance. Therefore, this paper constructs a comprehensive correction algorithm for income distribution using an improved Shapely value method. We analyze the operating mode of the power seller, and establish the net income calculation model under both independent and alliance operations. We then establish an alliance operation optimization model that considers the constraints of unit output, as well as the balance between supply and demand, with the goal of maximizing income. Finally, an industrial park in a province of northern China is taken as an example to verify the model’s practicability and effectiveness. The results show that the power sales alliance can effectively promote clean energy consumption. The maximum reduction in thermal power generation and CO2 is 8510 MW and 684.515 tons, respectively. We apply the algorithm to income distribution and find that the thermal power seller’s income increased by ¥1,463,870, which enhances the stability of the alliance. Therefore, our income distributing optimization model guarantees the interests of each participant to the greatest extent, and serves as an important reference for income distribution.

scholarly journals μDFL: A Secure Microchained Decentralized Federated Learning Fabric atop IoT Networks

2021 ◽  
Author(s):  
Ronghua Xu ◽  
Yu Chen
Keyword(s):  
Large Scale ◽  
Privacy Preservation ◽  
Security And Privacy ◽  
Small Scale ◽  
Proof Of Concept ◽  
Byzantine Fault Tolerance ◽  
Consensus Protocol ◽  
High Level ◽  
Collaborative Training ◽  
And Storage

<div>Federated Learning (FL) has been recognized as a privacy-preserving machine learning (ML) technology that enables collaborative training and learning of a global ML model based on the aggregation of distributed local model updates. However, security and privacy guarantees could be compromised due to malicious participants and the centralized aggregation manner. Possessing attractive features like decentralization, immutability and auditability, Blockchain is promising to enable a tamper-proof and trust-free framework to enhance performance and security in IoT based FL systems. However, directly integrating blockchains into the large scale IoT-based FL scenarios still faces many limitations, such as high computation and storage demands, low transactions throughput, poor scalability and challenges in privacy preservation. This paper proposes uDFL, a novel hierarchical IoT network fabric for decentralized federated learning (DFL) atop of a lightweight blockchain called microchain. Following the hierarchical infrastructure of FL, participants in uDFL are fragmented into multiple small scale microchains. Each microchain network relies on a hybrid Proof of Credit (PoC) block generation and Voting-based Chain Finality (VCF) consensus protocol to ensure efficiency and privacy-preservation at the network of edge. Meanwhile, microchains are federated vie a high-level inter-chain network, which adopts an efficient Byzantine Fault Tolerance (BFT) consensus protocol to achieve scalability and security.</div><div>A proof-of-concept prototype is implemented, and the experimental results verify the feasibility of the proposed uDFL solution in cross-devices FL settings with efficiency, security and privacy guarantees.</div>

Simulations of Multi-Phase Particle Deposition on Endwall Film-Cooling

2010 ◽  
Author(s):  
Seth A. Lawson ◽  
Karen A. Thole
Keyword(s):  
Particulate Matter ◽  
Film Cooling ◽  
Gas Turbines ◽  
Particle Deposition ◽  
Alternative Fuels ◽  
Large Scale ◽  
Phase Particle ◽  
Clean Energy ◽  
Multi Phase ◽  
Endwall Film Cooling

Demand for clean energy has increased motivation to design gas turbines capable of burning alternative fuels such as coal derived synthesis gas (syngas). One challenge associated with burning coal derived syngas is that trace amounts of particulate matter in the fuel and air can deposit on turbine hardware reducing the effectiveness of film cooling. For the current study, a method was developed to dynamically simulate multi-phase particle deposition through injection of a low melting temperature wax. The method was developed so the effects of deposition on endwall film cooling could be quantified using a large scale vane cascade in a low speed wind tunnel. A microcrystalline wax was injected into the mainstream flow using atomizing spray nozzles to simulate both solid and molten particulate matter in a turbine gas path. Infrared thermography was used to quantify cooling effectiveness with and without deposition at various locations on a film cooled endwall. Measured results indicated reductions in adiabatic effectiveness by as much as 30% whereby the reduction was highly dependent upon the location of the film-cooling holes relative to the vane.

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