Hasil untuk "Fuel"

Chuancheng Duan, J. Tong, Meng Shang et al.

Christina W. Li, J. Ciston, M. Kanan

R. Saidur, E. Abdelaziz, A. Demirbaş et al.

G. Merle, Matthias Wessling, Dc Kitty Nijmeijer

Recent years have seen extensive research on the preparation and properties of anion exchange membranes. Nevertheless, there is as yet no rigorous scientific classification of these membranes, and the methods of synthesis and characterization. The present review offers a practical classification based on the nature and the properties of anion exchange membranes for alkaline fuel cells, arrived at studying the relevant literature. This review also contains a description and assessment of all polymeric materials potentially suitable for use in alkaline fuel cells, and of their specific properties. Although there is ample literature on anion exchange membranes for various other applications, such as electrodialysis, the number of publications reporting alkaline fuel cell performance is still relatively low compared to their acidic homologues, the proton exchange membrane fuel cell. Two tables at the end of the manuscript offer the reader a comprehensive overview by listing all reviewed commercial and non-commercial anion exchange membranes. Suggestions for further research such as elucidation of the ionic transport mechanisms, AFC testing and important issues like the chemical stability and ionic conductivity are addressed as well.

A. Khaligh, Zhihao Li

Ó. Sánchez, C. Cardona

Rajesh Bashyam, P. Zelenay

Bidhya Kunwar, Huai N. Cheng, Sriram R. Chandrashekaran et al.

B. C. Ong, S. Kamarudin, S. Basri

Z. Pan, L. An, T. Zhao et al.

Abstract The last several decades have witnessed the rapid development of alkaline anion exchange membrane fuel cells (AAEMFCs) that possess a series of advantages as compared to acid proton exchange membrane fuel cells, such as the enhanced electrochemical kinetics of oxygen reduction reaction and the use of inexpensive non-platinum electrocatalysts, both of which are rendered by the alkaline medium. As an emerging power generation technology, the significant progress has been made in developing the alkaline anion exchange membrane fuel cells in recent years. This review article starts with a general description of the setup of AAEMFCs running on hydrogen and physical and chemical processes occurring in multi-layered porous structure. Then, the electrocatalytic materials and mechanisms for both hydrogen oxidation and oxygen reduction are introduced, including metal-based, metal oxide-based, and non-metal based electrocatalysts. In addition, the chemistries of alkaline anion exchange membranes (AAEMs), e.g. polymer backbone and function groups, are reviewed. The effects of pre-treatment, carbonate, and radiation on the performance of AAEMs are concluded as well. The effects of anode and cathode ionomers, structural designs, and water flooding on the performance of the single-cell are explained, and the durability and power output of a single-cell are summarized. Afterwards, two innovative system designs that are hybrid fuel cells and regenerative fuel cells are presented and mathematical modeling on mass transport phenomenon in AAEMFCs are highlighted. Finally, the challenges and perspectives for the future development of the AAEMFCs are discussed.

P. Pradhan, S. Mahajani, A. Arora

Abstract Bioenergy is the largest contributor of global renewables, simultaneously providing energy security to billions and stimulates rural development. The growing industrial demand of wood pellets for bioenergy coupled with sustainability issue have encouraged many to produce fuel pellets from non-woody biomass. The production and utilization of fuel pellets from varied feedstocks have therefore opened up opportunities and challenges for the existing technologies. The paper presents a state-of-the-art review on production and utilization of fuel pellets from biomass. This includes different aspects of pellet making process including pre-possessing of biomass for pelletization, influence of process parameters on pellet quality and various ways to utilize pellets. Finally the review ends with a discussion on the economic feasibility of fuel pellets for energy utilization.

Hai Wang, Rui Xu, Kun Wang et al.

Abstract Real distillate fuels usually contain thousands of hydrocarbon components. Over a wide range of combustion conditions, large hydrocarbon molecules undergo thermal decomposition to form a small set of low molecular weight fragments. In the case of conventional petroleum-derived fuels, the composition variation of the decomposition products is washed out due to the principle of large component number in real, multicomponent fuels. From a joint consideration of elemental conservation, thermodynamics and chemical kinetics, it is shown that the composition of the thermal decomposition products is a weak function of the thermodynamic condition, the fuel-oxidizer ratio and the fuel composition within the range of temperatures of relevance to flames and high temperature ignition. Based on these findings, we explore a hybrid chemistry (HyChem) approach to modeling the high-temperature oxidation of real, distillate fuels. In this approach, the kinetics of thermal and oxidative pyrolysis of the fuel is modeled using lumped kinetic parameters derived from experiments, while the oxidation of the pyrolysis fragments is described by a detailed reaction model. Sample model results are provided to support the HyChem approach.

Sivaprakash Sengodan, R. Lan, J. Humphreys et al.

Abstract One of the most attractive routes for the production of hydrogen or syngas for use in fuel cell applications is the reforming and partial oxidation of hydrocarbons. The use of hydrocarbons in high temperature fuel cells is achieved through either external or internal reforming. Reforming and partial oxidation catalysis to convert hydrocarbons to hydrogen rich syngas plays an important role in fuel processing technology. The current research in the area of reforming and partial oxidation of methane, methanol and ethanol includes catalysts for reforming and oxidation, methods of catalyst synthesis, and the effective utilization of fuel for both external and internal reforming processes. In this paper the recent progress in these areas of research is reviewed along with the reforming of liquid hydrocarbons, from this an overview of the current best performing catalysts for the reforming and partial oxidizing of hydrocarbons for hydrogen production is summarized.

C. Noor, M. M. Noor, R. Mamat

Abstract Transportation and shipping activities are major contributor to air pollution at sea where most of it occurs as a result of exhaust emissions from ships. Stringent emission limitations enforced by the International Maritime Organization have hastened the need to find a new alternative fuel for marine diesel engines. Thus, biodiesel fuel was chosen as one of the environmentally friendly alternative energy that can reduce ship toxic gas emissions and at the same time reduces dependence on petroleum-based fuels. Therefore, the purpose of this paper is to provide a comprehensive review of biodiesel as an alternative fuel for marine diesel engine applications. This review covers the biodiesel fuel background, engine performance, history, recent progress, engine warranty, issues, challenges, and possible solutions on using biodiesel for marine applications. A significant number of literatures from indexed journals were cited accordingly. The results of previous studies had shown that the use of biodiesel would mostly increase the amount of brake specific fuel consumption and nitrogen oxide gas while conversely reducing other toxic gas emissions. Although a number of issues and challenges arise, most marine engine manufacturers give conditional warranty against the use of biodiesel in the engines. The study concluded that biodiesel and its blends have a bright future in the marine sector, provided some of the highlighted issues can be solved.

Huicui Chen, Xin Zhao, Tong Zhang et al.

Abstract The short service life of fuel cell is a key problem that restricts the commercialization of fuel cell vehicles. Many scholars have found that gas starvation is one of the most important causes of the proton exchange membrane fuel cell lifetime decay, which leads to a series of severe consequences such as carbon support corrosion, cell reversal and output performance degradation. However, accurate diagnosis and effective mitigation of fuel cell gas starvation are not achieved currently. Gas starvation is a condition that the reaction gas of proton exchange membrane fuel cell working in the sub-stoichiometric state. In this paper, we will study the causes, severe consequences, diagnostic methods and mitigation measures of the gas starvation in proton exchange membrane fuel cells through previous literature review. This research is aim to provide guidance to the diagnose methods, to optimize the system control strategy and structure design and to contribute to the studies which are focus on prolong the proton exchange membrane fuel cell lifetime.

A. T. Sipra, Ningbo Gao, Haris Sarwar

Abstract With the realization of fossil fuels depletion, research has been started on the alternate energy sources. Biomass is a renewable energy source, from which bio-fuels can been produced. These bio-fuels are then used for power generation. Municipal solid waste (MSW) is a type of biomass which has been widely used in the production of bio-fuels. Since 1900s, studies have shown that a lot of research has been done in determining the optimum processes for producing bio-fuel through MSW. Pyrolysis is one of these processes. This process roots out various drawbacks which are present in other processes. It produces high grade pyrolysis fuel and reduces production cost. This review paper focuses on pyrolysis of MSW by using its components as a feedstock material with varying composition. The effects of interaction between different components of MSW and their heating values has been reviewed. The heating values are then compared with conventional fuels to highlight the significance of MSW pyrolysis products. The case of catalytic pyrolysis has also been reviewed and the corresponding heating values are compared to obtain high quality fuel. Moreover, a comparison has been made that how pyrolysis is an efficient process as compared to other processes.

Carlos F. Gould, Johannes Urpelainen

Liquefied petroleum gas (LPG) is by far the most popular clean cooking fuel in rural India, but how rural households use it remains poorly understood. Using the 2014-2015 ACCESS survey with over 8,500 households from six energy-poor Indian states, we offer a broad but detailed survey of LPG use in rural India. We find that (i) fuel costs are a critical obstacle to widespread adoption, (ii) fuel stacking is the prevailing norm as few households stop using firewood when adopting LPG, and (iii) both users and non-users have highly positive views of LPG as a convenient and clean cooking fuel. These findings show that expanding LPG use offers great promise in rural India, but affordability prevents a complete transition from traditional biomass to clean cooking fuels.

Yujie Wang, Zhendong Sun, Zonghai Chen

Abstract In recent years, fuel cell vehicles have attracted attention for their zero emission and environmental friendship. The sole fuel cell system cannot satisfy the dramatical change of motor power demands. In addition, the power fluctuations will damage the fuel cell stacks and shorten the cycle life of fuel cells. Therefore fuel cell systems are always combined with other energy storage devices like batteries and supercapacitors to increase the power density of the power system and fulfill the load power demands. The management strategy of the hybrid propulsion system is a significant technique for the vehicular power system. In this work, a finite state machine based management strategy is first proposed for both the battery/fuel cell and battery/supercapacitor/fuel cell system. The power capabilities of the battery and supercapacitor have been considered as important parameters in the management strategy. Moreover, an optimal oxygen excess ratio control is presented to maximize the fuel cell output net power. To evaluate the performance of the fuel economy and dynamic property, both the simulations and experimental verifications with the real physical system are given, and the real driving cycle of urban dynamometer driving schedule is utilized. The experimental and simulated results indicate that the proposed method is able to guarantee the required power during most of the driving cycles.

Kiran K. Yalamanchi, Pinaki Pal, Balaji Mohan et al.

In the present work, a generative deep learning framework combining a Co-optimized Variational Autoencoder (Co-VAE) architecture with quantitative structure-property relationship (QSPR) techniques is developed to enable accelerated inverse design of fuels. The Co-VAE integrates a property prediction component coupled with the VAE latent space, enhancing molecular reconstruction and accurate estimation of Research Octane Number (RON) (chosen as the fuel property of interest). A subset of the GDB-13 database, enriched with a curated RON database, is used for model training. Hyperparameter tuning is further utilized to optimize the balance among reconstruction fidelity, chemical validity, and RON prediction. An independent regression model is then used to refine RON prediction, while a differential evolution algorithm is employed to efficiently navigate the VAE latent space and identify promising fuel molecule candidates with high RON. This methodology addresses the limitations of traditional fuel screening approaches by capturing complex structure-property relationships within a comprehensive latent representation. The generative model can be adapted to different target properties, enabling systematic exploration of large chemical spaces relevant to fuel design applications. Furthermore, the demonstrated framework can be readily extended by incorporating additional synthesizability criteria to improve applicability and reliability for de novo design of new fuels.

Alessandro Contini, Davide Cacciarelli, Murat Kulahci

Accurate forecasting of jet fuel demand is crucial for optimizing supply chain operations in the aviation market. Fuel distributors specifically require precise estimates to avoid inventory shortages or excesses. However, there is a lack of studies that analyze the jet fuel demand forecasting problem using machine learning models. Instead, many industry practitioners rely on deterministic or expertise-based models. In this research, we evaluate the performance of data-driven approaches using a substantial amount of data obtained from a major aviation fuel distributor in the Danish market. Our analysis compares the predictive capabilities of traditional time series models, Prophet, LSTM sequence-to-sequence neural networks, and hybrid models. A key challenge in developing these models is the required forecasting horizon, as fuel demand needs to be predicted for the next 30 days to optimize sourcing strategies. To ensure the reliability of the data-driven approaches and provide valuable insights to practitioners, we analyze three different datasets. The primary objective of this study is to present a comprehensive case study on jet fuel demand forecasting, demonstrating the advantages of employing data-driven models and highlighting the impact of incorporating additional variables in the predictive models.