Energies最新文献

{"title":"Application of the Semi-Markov Processes to Model the Enercon E82-2 Preventive Wind Turbine Maintenance System","authors":"M. Szubartowski, K. Migawa, S. Borowski, A. Neubauer, Ľubomír Hujo, Beáta Kopiláková","doi":"10.3390/en17010199","DOIUrl":"https://doi.org/10.3390/en17010199","url":null,"abstract":"The share of wind energy in the energy mix is continuously increasing. However, a very important issue associated with its generation is the high failure rate of wind turbines. This situation particularly concerns large wind turbines, which are expensive and have a lower tolerance for system damage caused by various failures and faults. Vulnerable components include sensors, electronic control units, electrical systems, hydraulic systems, generators, gearboxes, rotor blades, and so on. As a result, significant emphasis is placed on improving the reliability, availability, and productivity of wind turbines. It is extremely important to detect and identify abnormalities as early as possible and predict potential failures and damages and the remaining useful life of components. One way to ensure turbine efficiency is to plan and implement preventive repairs. This work shows a semi-Markov model of a preventive maintenance system based on Enercon E82-2 wind turbines. The system’s performance quality is evaluated based on profit over time and an asymptotic availability coefficient. The developed model establishes formulas describing the efficiency functions and formulates the conditions for the existence of extremes (maxima) of these functions. Computational examples provided at the end of the paper illustrate the obtained research results. A preventive maintenance model is developed that can be applied to wind turbine hazard prevention (determining optimal times for wind turbine preventive maintenance).","PeriodicalId":11557,"journal":{"name":"Energies","volume":"8 22","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139148024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-Scale Characterization of Porosity and Cracks in Silicon Carbide Cladding after Transient Reactor Test Facility Irradiation","authors":"Fei Xu, Tiankai Yao, Peng Xu, J. Schulthess, Mario D. Matos, Sean Gonderman, Jack Gazza, Joshua J. Kane, Nikolaus L. Cordes","doi":"10.3390/en17010197","DOIUrl":"https://doi.org/10.3390/en17010197","url":null,"abstract":"Silicon carbide (SiC) ceramic matrix composite (CMC) cladding is currently being pursued as one of the leading candidates for accident-tolerant fuel (ATF) cladding for light water reactor applications. The morphology of fabrication defects, including the size and shape of voids, is one of the key challenges that impacts cladding performance and guarantees reactor safety. Therefore, quantification of defects’ size, location, distribution, and leak paths is critical to determining SiC CMC in-core performance. This research aims to provide quantitative insight into the defect’s distribution under multi-scale characterization at different length scales before and after different Transient Reactor Test Facility (TREAT) irradiation tests. A non-destructive multi-scale evaluation of irradiated SiC will help to assess critical microstructural defects from production and/or experimental testing to better understand and predict overall cladding performance. X-ray computed tomography (XCT), a non-destructive, data-rich characterization technique, is combined with lower length scale electronic microscopic characterization, which provides microscale morphology and structural characterization. This paper discusses a fully automatic workflow to detect and analyze SiC-SiC defects using image processing techniques on 3D X-ray images. Following the XCT data analysis, advanced characterizations from focused ion beam (FIB) and transmission electron microscopy (TEM) were conducted to verify the findings from the XCT data, especially quantitative results from local nano-scale TEM 3D tomography data, which were utilized to complement the 3D XCT results. In this work, three SiC samples (two irradiated and one unirradiated) provided by General Atomics are investigated. The irradiated samples were irradiated in a way that was expected to induce cracking, and indeed, the automated workflow developed in this work was able to successfully identify and characterize the defects formation in the irradiated samples while detecting no observed cracking in the unirradiated sample. These results demonstrate the value of automated XCT tools to better understand the damage and damage propagation in SiC-SiC structures for nuclear applications.","PeriodicalId":11557,"journal":{"name":"Energies","volume":" 3","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139142559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical Study on Compact Design in Marine Urea-SCR Systems for Small Ship Applications","authors":"Wontak Choi, Seunggi Choi, Sangkyung Na, Dongmin Shin, Hyomin Jeong, Yonmo Sung","doi":"10.3390/en17010187","DOIUrl":"https://doi.org/10.3390/en17010187","url":null,"abstract":"With increasingly stringent emissions legislation, such as that stipulated by the International Maritime Organization, for nitrogen oxide emission reduction in marine diesel engines, the imperative of curtailing nitrogen oxide emissions from marine diesel engines is intensifying. Consequently, the significance of aftertreatment technologies, including diesel particulate filters (DPFs) and selective catalytic reduction (SCR), is poised to grow substantially. In particular, a redesign is required to reduce the size of DPF and SCR systems for application in small ships. In this study, we varied the shape of the filters in DPF and SCR systems, aiming to achieve a distinct flow pattern and enable overall miniaturization. The performance metrics, including the nitric oxide (NO) reduction rate, NH3 slip rate, and pressure drop, of the redesigned models were compared with those of the conventional model. Computational fluid dynamics simulations were used to compare the performance of the redesigned model with that of the conventional model in terms of NO reduction and pressure drop. The redesigned system achieved a NO reduction rate of 6.9% below that of the conventional system, offering additional noteworthy benefits such as a 50% reduction in both pressure and overall length.","PeriodicalId":11557,"journal":{"name":"Energies","volume":" 12","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139142155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Efficient Electrothermal Model of a Thermoelectric Converter for a Thermal Energy Harvesting Process Simulation and Electronic Circuits Powering","authors":"P. Dziurdzia, P. Bratek, Michał Markiewicz","doi":"10.3390/en17010204","DOIUrl":"https://doi.org/10.3390/en17010204","url":null,"abstract":"This paper deals with an electrothermal model of a thermoelectric converter dedicated to performing simulations of coupled thermal and electrical phenomena taking place in harvesting processes. The proposed model is used to estimate the electrical energy gain from waste heat that would be sufficient to supply electronic circuits, in particular autonomous battery-less nodes of wireless sensor networks (WSN) and Internet of Things (IoT) devices. The developed model is not limited to low-power electronic solutions such as WSN or IoT; it can also be scaled up and applied to simulations of considerably higher thermal power conversion. In this paper, a few practical case studies are presented that show the feasibility and suitability of the proposed model for complex simultaneous simulation processes in both the electrical and thermal domains. The first example deals with a combined simulation of the electrothermal model of a thermoelectric generator (TEG) and an electronic harvester circuit based on Analog Devices’ power management integrated circuit LTC3108. The second example relates to the thermalization effect in heat sink-less harvesting applications that could be mitigated by a pulse mode operation. The unique contribution and advancement of the model is the hierarchical structure for scaling up and down, incorporating the complexity of the Seebeck effect, the Joule effect, heat conduction, as well as the temperature dependence of the used materials and the thermoelectric pellet geometries. The simulations can be performed in steady as well as transient states under changing electrical loads and temperatures.","PeriodicalId":11557,"journal":{"name":"Energies","volume":" 44","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139143201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structure and Thermoelectric Characterization of p-Type SnTe Nanobulk Material Synthesized by Charge Compensation Chemical Reaction","authors":"Ryosuke Fujiwara, Yuta Ikeda, Takuto Kawaguchi, Y. Takashima, T. Tsuruoka, K. Akamatsu","doi":"10.3390/en17010190","DOIUrl":"https://doi.org/10.3390/en17010190","url":null,"abstract":"SnTe is the most widely studied p-type thermoelectric (TE) alternative to PbTe. In this study, we prepared a nanostructured SnTe bulk material via spark plasma sintering from a precursor synthesized by a chemical precipitation process without using organic molecules. The sintered sample comprised tiny grains (100–300 nm) with high-density grain boundaries. Eventually, because the material would contain no impurities acting as scattering nodes of charge carriers, the material exhibited a relatively high electrical conductivity of 7.07 × 105 Sm−1 at 310 K. The material demonstrated low lattice thermal conductivity (0.87 Wm−1K−1 at 764 K), which can be owing to the increasing phonon scattering at grain boundaries. The maximum ZT was 0.31 at 764 K in the measured temperature range. This study provides a method for the design of phase-pure and surfactant-free SnTe thermoelectric materials that exhibit low lattice thermal conductivity and high carrier mobility using a chemical synthetic approach.","PeriodicalId":11557,"journal":{"name":"Energies","volume":" 16","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139144054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal Analysis and Capacity Planning of Solar Energy Demand-to-Supply Management: Case Study of a Logistics Distribution Center","authors":"Akihiko Takada, Hiromasa Ijuin, Masayuki Matsui, Tetsuo Yamada","doi":"10.3390/en17010191","DOIUrl":"https://doi.org/10.3390/en17010191","url":null,"abstract":"In recent years, global warming and environmental problems have become more serious due to greenhouse gas (GHG) emissions. Harvesting solar energy for production and logistic activities in supply chains, including factories and distribution centers, has been promoted as an effective means to reduce GHG emissions. However, it is difficult to balance the supply and demand of solar energy, owing to its intermittent nature, i.e., the output depends on the daylight and season. Moreover, the use of large-capacity solar power generation systems and batteries incurs higher installation costs. In order to maintain low costs, demand-to-supply management of solar energy, based on appropriate seasonal analysis of power generation and consumption and the capacity planning for power generation and the storage battery, is necessary. In this study, the on-demand cumulative control method is applied to actual power consumption data and solar power generation data estimated at a distribution center. Moreover, the monthly, seasonal, and temporal characteristics of power generation and consumption at the distribution center are analyzed. Additionally, the total amount of power purchased is investigated for solar energy demand-to-supply management.","PeriodicalId":11557,"journal":{"name":"Energies","volume":"84 4","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139146679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oxygen Carrier Circulation Rate for Novel Cold Flow Chemical Looping Reactors","authors":"Amanda E. Alain, Nicole K. Bond, Scott Champagne, Robin W. Hughes, Arturo Macchi","doi":"10.3390/en17010198","DOIUrl":"https://doi.org/10.3390/en17010198","url":null,"abstract":"To achieve net-zero emissions by the year 2050, carbon capture, utilization, and storage technologies must be implemented to decarbonize sectors with hard-to-abate emissions. Pressurized chemical looping (PCL) with a novel reactor design called a plug flow with internal recirculation (PFIR) fluidized bed is proposed as an attractive carbon capture technology to decarbonize small- and medium-scale emitters. The objective of this work is to examine the solid circulation rate between redox reactors in a cold flow chemical looping facility using an energy balance approach. The effects of static bed height, weir opening height, purge configuration, and gas flow rate on solid circulation rate were investigated. It was determined that parameters that greatly affected the total gas momentum, such as the fluidization ratio or number of purge rows, tended to also have a large effect on solid circulation rate. Parameters that had a small effect on total gas momentum, such as bed height, did not have a measurable effect on solid circulation rate. It was noted that parameters that posed a restriction to solids flow, such as a vertical purge jet or the weir itself, decreased the solid circulation rate compared to similar tests without restrictions.","PeriodicalId":11557,"journal":{"name":"Energies","volume":"7 4","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139147166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bibliometric Analysis of Renewable Energy Research on the Example of the Two European Countries: Insights, Challenges, and Future Prospects","authors":"Paweł Kut, K. Pietrucha-Urbanik","doi":"10.3390/en17010176","DOIUrl":"https://doi.org/10.3390/en17010176","url":null,"abstract":"Renewable energy sources, encompassing wind, solar, hydro, and geothermal options, are assuming an increasingly crucial role in the global energy landscape. They present a sustainable substitute for fossil fuels, effectively reducing greenhouse gas emissions and significantly contributing to the ongoing efforts against climate change. The widespread adoption of renewable energy technologies has undergone rapid expansion on a global scale, propelled by governmental policies, technological advancements, and decreasing costs. Despite their numerous advantages, renewable energy sources encounter challenges such as intermittent energy supply, storage solutions, and integration into existing power grids. Nevertheless, with sustained investment and innovation, renewable energy sources have the potential to become the predominant energy source of the future. This article conducts a bibliometric analysis of research on renewable energy sources in Poland and Germany. The analysis is grounded in publications catalogued in the Web of Science database, spanning the years from 1990 to 2023. The investigation delves into research topics related to renewable energy sources and scrutinizes the most frequently cited publications authored by individuals from these two countries. This bibliometric analysis stands out through its unique value proposition compared to other similar studies by placing a distinctive emphasis on critical research gaps, such as energy storage, smart grid technologies, and renewable energy in transportation. Additionally, the study’s focus on the specific trajectories of Poland and Germany in renewable energy adoption, coupled with the identification of key institutions with the highest centrality index, provides unparalleled insights into the evolving landscape of sustainable energy research. The findings from this study can serve as a valuable source of information for policymakers, researchers, and other stakeholders interested in promoting the advancement and utilization of renewable energy sources.","PeriodicalId":11557,"journal":{"name":"Energies","volume":"55 23","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139151090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical Study on Heat Generation Characteristics of Charge and Discharge Cycle of the Lithium-Ion Battery","authors":"Yuxuan Tan, Yue Li, Yueqing Gu, Wenjie Liu, Juan Fang, Chongchao Pan","doi":"10.3390/en17010178","DOIUrl":"https://doi.org/10.3390/en17010178","url":null,"abstract":"Lithium-ion batteries are the backbone of novel energy vehicles and ultimately contribute to a more sustainable and environmentally friendly transportation system. Taking a 5 Ah ternary lithium-ion battery as an example, a two-dimensional axisymmetric electrochemical–thermal coupling model is developed via COMSOL Multiphysics 6.0 in this study and then is validated with the experimental data. The proportion of different types of heat generation in a 26,650 ternary lithium-ion battery during the charge/discharge cycle is investigated numerically. Moreover, the impact of essential factors such as charge/discharge multiplier and ambient temperature on the reaction heat, ohmic heat, and polarization heat are analyzed separately. The numerical results indicate that the total heat generated by the constant discharge process is the highest in the charging and discharging cycle of a single battery. The maximum heat production per unit volume is 67,446.99 W/m3 at 2 C multiplier discharge. Furthermore, the polarization heat presents the highest percentage in the charge/discharge cycle, reaching up to 58.18% at 0 C and 1 C multiplier discharge. In a high-rate discharge, the proportion of the reaction heat decreases from 34.31% to 12.39% as the discharge rate increases from 0.5 C to 2 C. As the discharge rate rises and the ambient temperature falls, the maximum temperature increase of the single-cell battery also rises, with a more pronounced impact compared to increasing the discharge rate.","PeriodicalId":11557,"journal":{"name":"Energies","volume":"12 5","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139149662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metrics and Strategies Used in Power Grid Resilience","authors":"Cesar A. Vega Penagos, Jan L. Diaz, Omar F. Rodriguez-Martinez, Fabio Andrade, Adriana C. Luna","doi":"10.3390/en17010168","DOIUrl":"https://doi.org/10.3390/en17010168","url":null,"abstract":"This article provides a comprehensive review of power grid resilience, including current metrics and definitions, as well as the procedures used to ensure and improve the resilience of a system. We also describe the different strategies used by users to ensure their own resilience. Additionally, this article highlights areas for future research and opportunities for the integration of emerging technologies such as computer vision. The main objective of this study was to explore the metrics and strategies used in power grids and for the users to improve and ensure resilience in case of events.","PeriodicalId":11557,"journal":{"name":"Energies","volume":"34 5","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139149952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}