首页 > 最新文献

Energy Science & Engineering最新文献

英文 中文
Permeability of large-scale fractures with ununiform proppant distributions in coalbed methane development 煤层气开发中支撑剂分布不均匀的大尺度裂缝的渗透性
IF 3.5 3区 工程技术 Q3 ENERGY & FUELS Pub Date : 2024-07-03 DOI: 10.1002/ese3.1813
Jiaxiang Xu, Yang Zhao, Meizhu Wang, Dandan Dong, Zhe Liu, Jiaosheng Yang, Fenghua Tian

The coalbed methane (CBM) productivity is directly determined by the fracture permeability during hydraulic fracturing, which is regulated by the distribution of proppants. The proppant may be unevenly distributed in the fracture because of variables like the architecture of the fracture and the characteristics of the sand-carrying fluid. This study used two types of random functions to produce different ununiform distributions of proppant clusters in large-scale fractures, with the aim of investigating the effect of these distributions on the overall permeability of the fracture. A model of fluid-structure coupling is proposed. The closure of large-scale fractures under in-situ stress is analyzed using solid mechanics and the penalty function; the CBM flowing in proppant clusters and the high-speed channel between them is simulated using Darcy's law and the Navier–Stokes equation, respectively; and the overall permeability of fractures is computed using the fluid pressure drop throughout the fracture and the fluid flowing velocity in the fracture's outlet. Since most CBM flows along high-speed channels between the proppant clusters, the simulated findings show that the overall permeability of fractures with an uneven distribution of proppant clusters is significantly higher than that of the proppant cluster itself. As CBM becomes more discretely distributed, the proportion of CBM flowing within the proppant cluster continuously drops. As the permeability of the proppant cluster increases, the volume ratio of proppant clusters decreases, and the distribution of proppant clusters becomes more discrete, the overall permeability of the fracture continuously increases.

煤层气(CBM)的生产率直接取决于水力压裂过程中的裂缝渗透率,而裂缝渗透率受支撑剂分布的调节。由于裂缝结构和携砂液特性等变量的影响,支撑剂在裂缝中的分布可能不均匀。本研究使用两种随机函数在大尺度裂缝中产生不同的支撑剂簇均匀分布,目的是研究这些分布对裂缝整体渗透率的影响。提出了流体-结构耦合模型。利用固体力学和惩罚函数分析了原位应力作用下大尺度裂缝的闭合;分别利用达西定律和纳维-斯托克斯方程模拟了支撑剂簇和它们之间高速通道中流动的煤层气;利用整个裂缝中的流体压降和裂缝出口处的流体流速计算了裂缝的整体渗透率。由于大多数煤层气沿着支撑剂簇之间的高速通道流动,模拟结果表明,支撑剂簇分布不均的裂缝的整体渗透率明显高于支撑剂簇本身的渗透率。随着煤层气分布越来越分散,在支撑剂簇内流动的煤层气比例不断下降。随着支撑剂簇渗透率的增加、支撑剂簇体积比的减小以及支撑剂簇分布的离散化,裂缝的整体渗透率不断增加。
{"title":"Permeability of large-scale fractures with ununiform proppant distributions in coalbed methane development","authors":"Jiaxiang Xu,&nbsp;Yang Zhao,&nbsp;Meizhu Wang,&nbsp;Dandan Dong,&nbsp;Zhe Liu,&nbsp;Jiaosheng Yang,&nbsp;Fenghua Tian","doi":"10.1002/ese3.1813","DOIUrl":"10.1002/ese3.1813","url":null,"abstract":"<p>The coalbed methane (CBM) productivity is directly determined by the fracture permeability during hydraulic fracturing, which is regulated by the distribution of proppants. The proppant may be unevenly distributed in the fracture because of variables like the architecture of the fracture and the characteristics of the sand-carrying fluid. This study used two types of random functions to produce different ununiform distributions of proppant clusters in large-scale fractures, with the aim of investigating the effect of these distributions on the overall permeability of the fracture. A model of fluid-structure coupling is proposed. The closure of large-scale fractures under in-situ stress is analyzed using solid mechanics and the penalty function; the CBM flowing in proppant clusters and the high-speed channel between them is simulated using Darcy's law and the Navier–Stokes equation, respectively; and the overall permeability of fractures is computed using the fluid pressure drop throughout the fracture and the fluid flowing velocity in the fracture's outlet. Since most CBM flows along high-speed channels between the proppant clusters, the simulated findings show that the overall permeability of fractures with an uneven distribution of proppant clusters is significantly higher than that of the proppant cluster itself. As CBM becomes more discretely distributed, the proportion of CBM flowing within the proppant cluster continuously drops. As the permeability of the proppant cluster increases, the volume ratio of proppant clusters decreases, and the distribution of proppant clusters becomes more discrete, the overall permeability of the fracture continuously increases.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"12 7","pages":"3157-3170"},"PeriodicalIF":3.5,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.1813","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141547548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Cleaner isolation and application of sustainable new novel source of natural dye from tallow laureal (Litsea glutinosa) for silk dyeing 从乌桕月桂(Litsea glutinosa)中清洁分离和应用可持续的新型天然染料源,用于丝绸染色
IF 3.5 3区 工程技术 Q3 ENERGY & FUELS Pub Date : 2024-07-03 DOI: 10.1002/ese3.1835
Fazal-ur Rehman, Muhammad Abdul Qayyum, Kinza Zainab, Shahid Adeel, Noman Habib, Rony Mia, Muhammad Imran, Sidra Nasir

The utilization of waste plant residues in useful work particularly as the source of green dyes in textiles is now a days welcoming by global community. In this study, brown bollygum chips (Litsea glutinosa) called tallow laurel has been explored for silk dyeing using ecofriendly approaches. Extraction has been done in suitable medium and utilized onto fabric before and after microwave (MW) treatment up to 10 min. Response surface methodology was employed to observe the significant of selected dyeing parameters at which shade development with improved colorfastness was observed. It was found that 2 min radiation to both acidic extract of tallow laureal and silk fabric is the useful condition to get colorfast shade when employed before and after mordanting with iron salt and tannic acid solution as eco-chemical agent, whereas with walnut bark and pine nut hulls extract as eco bio agents. The highest color strength value of 4.58 was observed using tannic acid as postchemical mordant for silk dyeing. The standard methods for fastness as per ISO to light, washing, and rubbing reveal that using selected shades made under ecofriendly cost time and energy effective conditions, stable colorfast hues were rated good with the value of 4/5. Therefore, it is recommended that MW treatment in addition with statistical approach i.e., central composite design used for exploring new dye yielding plant, then using eco-mordanting technique will help in getting promising colorfast shades.

利用废弃植物残渣进行有用的工作,特别是作为纺织品的绿色染料来源,如今正受到全球社会的欢迎。在这项研究中,利用生态友好的方法,探索了被称为 "乌桕月桂 "的棕色宝丽金片(Litsea glutinosa)在丝绸染色中的应用。在合适的介质中进行萃取,并在微波(MW)处理前后将其用于织物上,最长时间为 10 分钟。采用响应面方法观察选定染色参数的显著性,在此参数下可观察到色泽发展和色牢度的改善。结果发现,在用铁盐和单宁酸溶液作为生态化学剂,而用核桃皮和松子壳提取物作为生态生物剂进行媒染之前和之后,对牛脂月桂酸性提取物和丝织物进行 2 分钟辐射是获得不褪色的有效条件。使用单宁酸作为丝绸染色的后化学媒染剂,观察到最高的色牢度值为 4.58。根据国际标准化组织规定的耐光、耐洗和耐摩擦色牢度标准方法,使用在生态友好、节省时间和能源的条件下制成的选定色调,稳定的不褪色色调被评为良好,值为 4/5。因此,建议在采用中心复合设计这种统计方法探索新的染料生产植物时,在使用 MW 处理技术的同时,再使用生态媒染技术,这将有助于获得具有前景的不褪色色调。
{"title":"Cleaner isolation and application of sustainable new novel source of natural dye from tallow laureal (Litsea glutinosa) for silk dyeing","authors":"Fazal-ur Rehman,&nbsp;Muhammad Abdul Qayyum,&nbsp;Kinza Zainab,&nbsp;Shahid Adeel,&nbsp;Noman Habib,&nbsp;Rony Mia,&nbsp;Muhammad Imran,&nbsp;Sidra Nasir","doi":"10.1002/ese3.1835","DOIUrl":"10.1002/ese3.1835","url":null,"abstract":"<p>The utilization of waste plant residues in useful work particularly as the source of green dyes in textiles is now a days welcoming by global community. In this study, brown bollygum chips (<i>Litsea glutinosa</i>) called tallow laurel has been explored for silk dyeing using ecofriendly approaches. Extraction has been done in suitable medium and utilized onto fabric before and after microwave (MW) treatment up to 10 min. Response surface methodology was employed to observe the significant of selected dyeing parameters at which shade development with improved colorfastness was observed. It was found that 2 min radiation to both acidic extract of tallow laureal and silk fabric is the useful condition to get colorfast shade when employed before and after mordanting with iron salt and tannic acid solution as eco-chemical agent, whereas with walnut bark and pine nut hulls extract as eco bio agents. The highest color strength value of 4.58 was observed using tannic acid as postchemical mordant for silk dyeing. The standard methods for fastness as per ISO to light, washing, and rubbing reveal that using selected shades made under ecofriendly cost time and energy effective conditions, stable colorfast hues were rated good with the value of 4/5. Therefore, it is recommended that MW treatment in addition with statistical approach i.e., central composite design used for exploring new dye yielding plant, then using eco-mordanting technique will help in getting promising colorfast shades.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"12 9","pages":"3718-3729"},"PeriodicalIF":3.5,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.1835","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141547549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The role of ceria in promoting Ni catalysts supported on phosphate-modified zirconia for the partial oxidation of methane 铈在促进以磷酸盐改性氧化锆为载体的镍催化剂进行甲烷部分氧化中的作用
IF 3.5 3区 工程技术 Q3 ENERGY & FUELS Pub Date : 2024-07-02 DOI: 10.1002/ese3.1820
Abdulaziz A. M. Abahussain, Ahmed S. Al-Fatesh, Dharmesh M. Vadodariya, Jehad K. Abu-Dahrieh, Khaled M. Banabdwin, Naif Alarifi, Ahmed A. Ibrahim, Anis H. Fakeeha, Ahmed E. Abasaeed, Rawesh Kumar

The catalytic partial oxidation of methane (POM) is aimed at the mitigation of CH4 (a highly potent greenhouse gas) from the environment and the synthesis of syngas with a high H2/CO ratio. Herein, to enhance the POM reaction, Ni-supported phosphate-modified-zirconia were synthesized with promotor “Ce” to achieve high H2/CO ratio (2.4–3.2). The catalysts were characterized by surface area and porosity, X-ray diffraction, RAMAN, temperature-programmed experiments (TPR, CO2-TPD, and TPO), and TEM. Increasing the ceria addition over 10Ni/PO4 + ZrO2 resulted in lower crystallinity, higher dispersion of active sites, and enhanced the surface area of catalyst. The unique and prominent reducibility and basicity of NiO-species and surface oxide ions, respectively, are particularly notable at 4 wt.% ceria loading. At a reaction temperature of 600°C, the highest concentration of active sites and a unique concentration of moderate strength basic sites can be achieved with 4 wt.% ceria loading over 10Ni/PO4 + ZrO2. This leads to 44% conversion of CH4, 36% yield of H2, 35% yield of CO2, and H2/CO ratio of 3.16 for the POM reaction. The cyclic H2TPR-O2TPO-H2TPR experiment confirms the reorganization of the active site towards high temperature under oxidizing gas O2 and reducing gas H2 gas stream during the POM reaction.

催化甲烷部分氧化(POM)的目的是减少环境中的甲烷(CH4)(一种强效温室气体),并合成高 H2/CO 比的合成气。为了提高 POM 反应的效果,我们在镍支撑的磷酸盐改性氧化锆中加入了促进剂 "Ce",以实现高 H2/CO 比(2.4-3.2)。催化剂的表征包括表面积和孔隙率、X 射线衍射、RAMAN、温度编程实验(TPR、CO2-TPD 和 TPO)和 TEM。在 10Ni/PO4 + ZrO2 上增加铈的添加量可降低结晶度,提高活性位点的分散度,并增加催化剂的表面积。铈含量为 4 wt.%时,NiO 物种和表面氧化物离子分别具有独特而突出的还原性和碱性。在 600°C 的反应温度下,10Ni/PO4 + ZrO2 的铈负载量为 4 wt.%时,活性位点的浓度最高,中等强度的碱性位点的浓度也很独特。这使得 POM 反应的 CH4 转化率达到 44%,H2 产率达到 36%,CO2 产率达到 35%,H2/CO 比率达到 3.16。循环 H2TPR-O2TPO-H2TPR 实验证实,在氧化性气体 O2 和还原性气体 H2 的气流作用下,POM 反应的活性位点向高温方向重组。
{"title":"The role of ceria in promoting Ni catalysts supported on phosphate-modified zirconia for the partial oxidation of methane","authors":"Abdulaziz A. M. Abahussain,&nbsp;Ahmed S. Al-Fatesh,&nbsp;Dharmesh M. Vadodariya,&nbsp;Jehad K. Abu-Dahrieh,&nbsp;Khaled M. Banabdwin,&nbsp;Naif Alarifi,&nbsp;Ahmed A. Ibrahim,&nbsp;Anis H. Fakeeha,&nbsp;Ahmed E. Abasaeed,&nbsp;Rawesh Kumar","doi":"10.1002/ese3.1820","DOIUrl":"10.1002/ese3.1820","url":null,"abstract":"<p>The catalytic partial oxidation of methane (POM) is aimed at the mitigation of CH<sub>4</sub> (a highly potent greenhouse gas) from the environment and the synthesis of syngas with a high H<sub>2</sub>/CO ratio. Herein, to enhance the POM reaction, Ni-supported phosphate-modified-zirconia were synthesized with promotor “Ce” to achieve high H<sub>2</sub>/CO ratio (2.4–3.2). The catalysts were characterized by surface area and porosity, X-ray diffraction, RAMAN, temperature-programmed experiments (TPR, CO<sub>2</sub>-TPD, and TPO), and TEM. Increasing the ceria addition over 10Ni/PO<sub>4</sub> + ZrO<sub>2</sub> resulted in lower crystallinity, higher dispersion of active sites, and enhanced the surface area of catalyst. The unique and prominent reducibility and basicity of NiO-species and surface oxide ions, respectively, are particularly notable at 4 wt.% ceria loading. At a reaction temperature of 600°C, the highest concentration of active sites and a unique concentration of moderate strength basic sites can be achieved with 4 wt.% ceria loading over 10Ni/PO<sub>4</sub> + ZrO<sub>2</sub>. This leads to 44% conversion of CH<sub>4</sub>, 36% yield of H<sub>2</sub>, 35% yield of CO<sub>2</sub>, and H<sub>2</sub>/CO ratio of 3.16 for the POM reaction. The cyclic H<sub>2</sub>TPR-O<sub>2</sub>TPO-H<sub>2</sub>TPR experiment confirms the reorganization of the active site towards high temperature under oxidizing gas O<sub>2</sub> and reducing gas H<sub>2</sub> gas stream during the POM reaction.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"12 8","pages":"3379-3389"},"PeriodicalIF":3.5,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.1820","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141527457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
DFT simulations of photovoltaic parameters of dye-sensitized solar cells with new efficient sensitizer of indolo[3, 2-b]carbazole complexes 使用新型高效敏化剂吲哚并[3, 2-b]咔唑复合物的染料敏化太阳能电池光伏参数的 DFT 模拟
IF 3.5 3区 工程技术 Q3 ENERGY & FUELS Pub Date : 2024-07-01 DOI: 10.1002/ese3.1834
Muhammad Usman Khan, Abida Anwar, Abrar Ul Hassan, Saad M. Alshehri, Amir Sohail

Developing economical and high-performing sensitizers is crucial in advancing dye-sensitized solar cells (DSSCs) and optoelectronics. This research paper explores the potential of novel red light-absorbing organic dyes based on Indolo[3,2-b]carbazole (ICZ) as the donor applied in co-sensitizer-free DSSCs for breakthroughs in photovoltaic (PV) applications. DFT and TD-DFT based computational methods were employed to calculate the conduction band levels, electron injection capabilities, and power conversion efficiency (PCE) of metal-free organic dyes (ICZ1–ICZ9) having D-A-π-A architecture. Comprehensive analyses included NBO, DOS, FMO, ICT, MEP, binding energy, and TDM analysis. Quantum chemical calculations of the structural, photochemical, and electrochemical properties, as well as the key parameters, reveals that all the designed dyes could be an excellent candidate for high-efficiency DSSCs due the small energy gap (2.130–1.947 eV), longer wavelength absorption (759.47–520.63 nm), longer lifetimes (15.65–6.67 ns), a lower ΔGreg (0.29–0.14 eV), a significant dipole moment changes (31.489–16.195D), LHE (0.95-0.46), the large qCT (0.962–0.689), small DCT (7.657, 4.897 Å), and VOC (1.13–0.86 eV). This quantum simulation showed that, when compared to reference D8, the photovoltaic dyes ICZ8, ICZ2, and ICZ7 are recognized as being eye-catching. Furthermore, dye@(TiO2)9 cluster model results demonstrate promising prospects for enhancing the photovoltaic (PV) performance of ICZ1–ICZ9 dyes by electron injection and conduction band (CB) engineering. This study will help the experimentalists for developing ICZ-based PVs as more efficient and sustainable energy solutions.

开发经济、高性能的敏化剂对于推动染料敏化太阳能电池(DSSC)和光电子学的发展至关重要。本研究论文探讨了基于吲哚并[3,2-b]咔唑(ICZ)作为给体的新型红光吸收有机染料在无助敏剂 DSSC 中的应用潜力,以期在光伏(PV)应用领域取得突破。研究人员采用基于 DFT 和 TD-DFT 的计算方法计算了具有 D-A-π-A 结构的无金属有机染料(ICZ1-ICZ9)的传导带电平、电子注入能力和功率转换效率 (PCE)。综合分析包括 NBO、DOS、FMO、ICT、MEP、结合能和 TDM 分析。对结构、光化学和电化学特性以及关键参数进行的量子化学计算表明,由于能隙小(2.130-1.947 eV)、较长的吸收波长(759.47-520.63 nm)、较长的寿命(15.65-6.67 ns)、较低的ΔGreg(0.29-0.14 eV)、偶极矩变化明显(31.489-16.195D)、LHE(0.95-0.46)、qCT 大(0.962-0.689)、DCT 小(7.657、4.897 Å)和 VOC(1.13-0.86 eV)。该量子模拟显示,与参考 D8 相比,光电染料 ICZ8、ICZ2 和 ICZ7 被公认为引人注目。此外,dye@(TiO2)9 团簇模型结果表明,通过电子注入和导带(CB)工程提高 ICZ1-ICZ9 染料的光伏(PV)性能前景广阔。这项研究将有助于实验人员开发基于 ICZ 的光伏技术,使其成为更高效、更可持续的能源解决方案。
{"title":"DFT simulations of photovoltaic parameters of dye-sensitized solar cells with new efficient sensitizer of indolo[3, 2-b]carbazole complexes","authors":"Muhammad Usman Khan,&nbsp;Abida Anwar,&nbsp;Abrar Ul Hassan,&nbsp;Saad M. Alshehri,&nbsp;Amir Sohail","doi":"10.1002/ese3.1834","DOIUrl":"10.1002/ese3.1834","url":null,"abstract":"<p>Developing economical and high-performing sensitizers is crucial in advancing dye-sensitized solar cells (DSSCs) and optoelectronics. This research paper explores the potential of novel red light-absorbing organic dyes based on Indolo[3,2-b]carbazole (ICZ) as the donor applied in co-sensitizer-free DSSCs for breakthroughs in photovoltaic (PV) applications. DFT and TD-DFT based computational methods were employed to calculate the conduction band levels, electron injection capabilities, and power conversion efficiency (PCE) of metal-free organic dyes (ICZ1–ICZ9) having D-A-π-A architecture. Comprehensive analyses included NBO, DOS, FMO, ICT, MEP, binding energy, and TDM analysis. Quantum chemical calculations of the structural, photochemical, and electrochemical properties, as well as the key parameters, reveals that all the designed dyes could be an excellent candidate for high-efficiency DSSCs due the small energy gap (2.130–1.947 eV), longer wavelength absorption (759.47–520.63 nm), longer lifetimes (15.65–6.67 ns), a lower Δ<i>G</i><sub>reg</sub> (0.29–0.14 eV), a significant dipole moment changes (31.489–16.195D), LHE (0.95-0.46), the large <i>q</i><sup>CT</sup> (0.962–0.689), small <i>D</i><sup>CT</sup> (7.657, 4.897 Å), and <i>V</i><sub>OC</sub> (1.13–0.86 eV). This quantum simulation showed that, when compared to reference D8, the photovoltaic dyes ICZ8, ICZ2, and ICZ7 are recognized as being eye-catching. Furthermore, dye@(TiO<sub>2</sub>)<sub>9</sub> cluster model results demonstrate promising prospects for enhancing the photovoltaic (PV) performance of ICZ1–ICZ9 dyes by electron injection and conduction band (CB) engineering. This study will help the experimentalists for developing ICZ-based PVs as more efficient and sustainable energy solutions.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"12 9","pages":"3681-3703"},"PeriodicalIF":3.5,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.1834","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141527458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Optimization of governor parameters for transient process of hydropower system with two turbine units sharing a super long headrace tunnel 优化两台水轮机组共用超长扬程隧洞的水电系统暂态过程的调速器参数
IF 3.5 3区 工程技术 Q3 ENERGY & FUELS Pub Date : 2024-07-01 DOI: 10.1002/ese3.1832
Wencheng Guo, Li Wang, Fangle Qu

The governor parameters affect the stability and regulation quality of hydropower system with two turbine units sharing a super long headrace tunnel (SLHT). To improve the transient process of hydropower system, this study investigates the optimization of governor parameters. First, the model of hydropower system with two turbine units sharing an SLHT is established. Second, the optimization scheme of governor parameters for transient process of hydropower system is designed by genetic algorithm. The mathematical formulation of genetic algorithm is illuminated. The implementation procedure of genetic algorithm is illustrated. Then, the optimization results of governor parameters by genetic algorithm are analyzed by illustrating the regulation quality of hydropower system under two operating conditions. Finally, the effect of asymmetrical factors on optimal governor parameters is revealed. The asymmetrical layout of bifurcated penstocks, asymmetrical layout of turbine units, and asymmetrical load disturbances are considered. The results indicate that the objective function of hydropower system is composed of the dynamic indexes for frequency oscillations of two turbine units and water level oscillation in surge tank. The fitness function evolves in the direction that makes the regulation quality of hydropower system become better. Under the symmetrical or asymmetrical bifurcated penstocks, turbine units, and load disturbances, the optimal parameters of governors are asymmetrical. The regulation quality of hydropower system under the governor parameters of genetic algorithm is obviously better than that under the governor parameters of Stein formula. The optimal governor parameters are directly affected by the asymmetrical factors of hydropower system. With the increase of the flow inertia of one bifurcated penstock, the optimal parameters of the other governor become greater.

调速器参数会影响共用超长顶管隧洞(SLHT)的两台水轮机组水电系统的稳定性和调节质量。为改善水电系统的暂态过程,本研究对调速器参数进行了优化。首先,建立了两台水轮机组共用超长顶管隧洞的水电系统模型。其次,利用遗传算法设计了水电系统暂态过程的调速器参数优化方案。阐明了遗传算法的数学公式。说明了遗传算法的实现过程。然后,通过说明两种运行条件下水电系统的调节质量,分析了遗传算法对调速器参数的优化结果。最后,揭示了非对称因素对最优调速器参数的影响。考虑了分岔水闸的非对称布局、水轮机组的非对称布局和非对称负荷干扰。结果表明,水电系统的目标函数由两台水轮机组的频率振荡和涌水槽水位振荡的动态指标组成。拟合函数的发展方向是使水电系统的调节质量变得更好。在对称或不对称的分岔水闸、水轮机组和负荷扰动条件下,调速器的最优参数是不对称的。遗传算法调速器参数下的水电系统调节质量明显优于斯坦因公式调速器参数下的水电系统调节质量。最优调速器参数直接受到水电系统不对称因素的影响。随着一个分岔水闸流量惯性的增大,另一个调速器的最优参数也随之增大。
{"title":"Optimization of governor parameters for transient process of hydropower system with two turbine units sharing a super long headrace tunnel","authors":"Wencheng Guo,&nbsp;Li Wang,&nbsp;Fangle Qu","doi":"10.1002/ese3.1832","DOIUrl":"10.1002/ese3.1832","url":null,"abstract":"<p>The governor parameters affect the stability and regulation quality of hydropower system with two turbine units sharing a super long headrace tunnel (SLHT). To improve the transient process of hydropower system, this study investigates the optimization of governor parameters. First, the model of hydropower system with two turbine units sharing an SLHT is established. Second, the optimization scheme of governor parameters for transient process of hydropower system is designed by genetic algorithm. The mathematical formulation of genetic algorithm is illuminated. The implementation procedure of genetic algorithm is illustrated. Then, the optimization results of governor parameters by genetic algorithm are analyzed by illustrating the regulation quality of hydropower system under two operating conditions. Finally, the effect of asymmetrical factors on optimal governor parameters is revealed. The asymmetrical layout of bifurcated penstocks, asymmetrical layout of turbine units, and asymmetrical load disturbances are considered. The results indicate that the objective function of hydropower system is composed of the dynamic indexes for frequency oscillations of two turbine units and water level oscillation in surge tank. The fitness function evolves in the direction that makes the regulation quality of hydropower system become better. Under the symmetrical or asymmetrical bifurcated penstocks, turbine units, and load disturbances, the optimal parameters of governors are asymmetrical. The regulation quality of hydropower system under the governor parameters of genetic algorithm is obviously better than that under the governor parameters of Stein formula. The optimal governor parameters are directly affected by the asymmetrical factors of hydropower system. With the increase of the flow inertia of one bifurcated penstock, the optimal parameters of the other governor become greater.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"12 8","pages":"3505-3523"},"PeriodicalIF":3.5,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.1832","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141527456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Numerical simulation of the influence of the structural parameters of a sampling diluter for particulate matter in diesel engines on the internal flow field and dilution ratio 柴油发动机颗粒物取样稀释器结构参数对内部流场和稀释率影响的数值模拟
IF 3.5 3区 工程技术 Q3 ENERGY & FUELS Pub Date : 2024-06-27 DOI: 10.1002/ese3.1761
Limin Geng, Yang Zhao, Guifen Sheng, Nan Gao, Yonggang Xiao, Feichuang Huang, Hao Chen

This study investigated how structural parameters (including injection ducts and exhaust nozzle inner diameters) affect the internal flow field and dilution ratio of diesel particulate sampling diluters. Increasing air injection duct diameter increased the injection chamber pressure and decreased the air velocity peak, mixed gas flow velocity, sample temperature, and mixing rate. Excessively small tube diameters caused uneven and discontinuous flow field distributions, while substantial air blockage rendered the flow state poor. Increasing nozzle inner diameters increased the exhaust flow area and the sample temperature, but decreased the velocity of the exhaust and gas mixtures and the pressure drop. Compared with a 2.0 mm inner diameter, 2.5 and 3.0 mm diameters decreased the peak velocity by 11.18% and 14.41%, respectively, and mixing slowed significantly. Inner nozzle diameters of <1.5 mm increased the pressure drop significantly; the exhaust velocity also increased, exceeding the air velocity at the mixing position. The dilution ratio and relative error decreased with increasing inner nozzle diameter. At an air injection duct and an inner nozzle diameter of 0.1 and 2.0 mm, respectively, the dilutor's flow field distribution improved, the mixed gas flow stabilized, and the dilution ratio and relative error were 21.34% and 6.74%, respectively.

本研究探讨了结构参数(包括喷射管道和排气喷嘴内径)如何影响柴油微粒采样稀释器的内部流场和稀释率。增加空气喷射管直径会增加喷射室压力,降低空气流速峰值、混合气体流速、样品温度和混合率。过小的管道直径会导致流场分布不均匀和不连续,而大量的空气阻塞会使流动状态变差。增加喷嘴内径可增加排气流动面积和样品温度,但会降低排气和气体混合物的速度和压降。与内径为 2.0 毫米的喷嘴相比,内径为 2.5 毫米和 3.0 毫米的喷嘴的峰值速度分别降低了 11.18% 和 14.41%,混合速度明显减慢。内径为 1.5 毫米的喷嘴大大增加了压降;排气速度也增加了,超过了混合位置的空气速度。稀释率和相对误差随着内喷嘴直径的增大而减小。当空气注入管道和内喷嘴直径分别为 0.1 毫米和 2.0 毫米时,稀释器的流场分布得到改善,混合气体流量趋于稳定,稀释率和相对误差分别为 21.34% 和 6.74%。
{"title":"Numerical simulation of the influence of the structural parameters of a sampling diluter for particulate matter in diesel engines on the internal flow field and dilution ratio","authors":"Limin Geng,&nbsp;Yang Zhao,&nbsp;Guifen Sheng,&nbsp;Nan Gao,&nbsp;Yonggang Xiao,&nbsp;Feichuang Huang,&nbsp;Hao Chen","doi":"10.1002/ese3.1761","DOIUrl":"10.1002/ese3.1761","url":null,"abstract":"<p>This study investigated how structural parameters (including injection ducts and exhaust nozzle inner diameters) affect the internal flow field and dilution ratio of diesel particulate sampling diluters. Increasing air injection duct diameter increased the injection chamber pressure and decreased the air velocity peak, mixed gas flow velocity, sample temperature, and mixing rate. Excessively small tube diameters caused uneven and discontinuous flow field distributions, while substantial air blockage rendered the flow state poor. Increasing nozzle inner diameters increased the exhaust flow area and the sample temperature, but decreased the velocity of the exhaust and gas mixtures and the pressure drop. Compared with a 2.0 mm inner diameter, 2.5 and 3.0 mm diameters decreased the peak velocity by 11.18% and 14.41%, respectively, and mixing slowed significantly. Inner nozzle diameters of &lt;1.5 mm increased the pressure drop significantly; the exhaust velocity also increased, exceeding the air velocity at the mixing position. The dilution ratio and relative error decreased with increasing inner nozzle diameter. At an air injection duct and an inner nozzle diameter of 0.1 and 2.0 mm, respectively, the dilutor's flow field distribution improved, the mixed gas flow stabilized, and the dilution ratio and relative error were 21.34% and 6.74%, respectively.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"12 7","pages":"2785-2797"},"PeriodicalIF":3.5,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.1761","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141508195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Deformation, fracture, and energy evolution characteristics of coal-rock under dynamic–static combined loading 动静联合加载下煤岩的变形、断裂和能量演化特征
IF 3.5 3区 工程技术 Q3 ENERGY & FUELS Pub Date : 2024-06-27 DOI: 10.1002/ese3.1825
Wei Li, Zhizhen Zhang, Yeqi Teng, Hao Wang, Cao Man, Menghan Ren, Xiaoji Shang, Linming Dou, Feng Gao

Deep coal-rock formations are subjected to complex stress environments characterized by high static stresses and dynamic disturbances. To study the damage, fracture, and energy evolution characteristics of coal-rock under dynamic–static combined loading, a new multiscale constitutive model for coal-rock under dynamic–static combined loading is proposed based on micromechanics, and it is implemented into the LS-DYNA solver. A numerical model of coal-rock Split Hopkinson Pressure Bar under dynamic–static combined loading is established using LS-DYNA, and research on the mechanical and energy evolution characteristics of coal-rock under one-dimensional and three-dimensional dynamic–static combined loading is conducted. The results show that under one-dimensional dynamic–static combined loading, with the increase of precompression, the dynamic peak stress linearly decreases while the combined peak stress linearly increases, and the dissipated energy of the specimen shows a decreasing trend. The fracture patterns of the coal-rock specimen include internal shear fracture and external tensile fracture, and eventually, these two modes of fracture intersect to form macroscopic mesh cracks. As the axial pressure increases, the degree of specimen fragmentation gradually increases. Under three-dimensional dynamic–static combined loading, with the increase of preconfining pressure, the stress–strain curve of the specimen will transition from “stress drop” to “stress rebound” after the peak. The peak stress increases with the increase of confining pressure, and the energy dissipation density of the specimen increases first and then decreases with the increase of confining pressure. With the increase of confining pressure, the hoop deformation of the specimen plays a constraining role, and the degree of specimen fracture gradually weakens, and the time of fracture occurrence gradually delays. The research results contribute to revealing the mechanical and energy mechanisms of rockburst disasters in deep coal mines.

深部煤岩层承受着以高静态应力和动态扰动为特征的复杂应力环境。为研究煤岩在动静联合荷载作用下的损伤、断裂和能量演化特征,提出了基于微观力学的煤岩在动静联合荷载作用下的新型多尺度构成模型,并将其应用于 LS-DYNA 求解器中。利用LS-DYNA建立了动静联合加载下煤岩分体霍普金森压杆的数值模型,并对煤岩在一维和三维动静联合加载下的力学和能量演化特性进行了研究。结果表明,在一维动静联合加载下,随着预压缩量的增大,动峰值应力线性减小,而联合峰值应力线性增大,试样耗散能量呈减小趋势。煤岩试样的断裂模式包括内部剪切断裂和外部拉伸断裂,最终这两种断裂模式相交形成宏观网状裂缝。随着轴向压力的增加,试样的破碎程度逐渐增加。在三维动静联合加载下,随着预约束压力的增加,试样的应力-应变曲线在达到峰值后会从 "应力下降 "过渡到 "应力回升"。峰值应力随约束压力的增加而增大,试样的能量耗散密度随约束压力的增加先增大后减小。随着约束压力的增加,试样的箍筋变形起约束作用,试样断裂程度逐渐减弱,断裂发生时间逐渐推迟。该研究成果有助于揭示深部煤矿岩爆灾害的力学和能量机理。
{"title":"Deformation, fracture, and energy evolution characteristics of coal-rock under dynamic–static combined loading","authors":"Wei Li,&nbsp;Zhizhen Zhang,&nbsp;Yeqi Teng,&nbsp;Hao Wang,&nbsp;Cao Man,&nbsp;Menghan Ren,&nbsp;Xiaoji Shang,&nbsp;Linming Dou,&nbsp;Feng Gao","doi":"10.1002/ese3.1825","DOIUrl":"10.1002/ese3.1825","url":null,"abstract":"<p>Deep coal-rock formations are subjected to complex stress environments characterized by high static stresses and dynamic disturbances. To study the damage, fracture, and energy evolution characteristics of coal-rock under dynamic–static combined loading, a new multiscale constitutive model for coal-rock under dynamic–static combined loading is proposed based on micromechanics, and it is implemented into the LS-DYNA solver. A numerical model of coal-rock Split Hopkinson Pressure Bar under dynamic–static combined loading is established using LS-DYNA, and research on the mechanical and energy evolution characteristics of coal-rock under one-dimensional and three-dimensional dynamic–static combined loading is conducted. The results show that under one-dimensional dynamic–static combined loading, with the increase of precompression, the dynamic peak stress linearly decreases while the combined peak stress linearly increases, and the dissipated energy of the specimen shows a decreasing trend. The fracture patterns of the coal-rock specimen include internal shear fracture and external tensile fracture, and eventually, these two modes of fracture intersect to form macroscopic mesh cracks. As the axial pressure increases, the degree of specimen fragmentation gradually increases. Under three-dimensional dynamic–static combined loading, with the increase of preconfining pressure, the stress–strain curve of the specimen will transition from “stress drop” to “stress rebound” after the peak. The peak stress increases with the increase of confining pressure, and the energy dissipation density of the specimen increases first and then decreases with the increase of confining pressure. With the increase of confining pressure, the hoop deformation of the specimen plays a constraining role, and the degree of specimen fracture gradually weakens, and the time of fracture occurrence gradually delays. The research results contribute to revealing the mechanical and energy mechanisms of rockburst disasters in deep coal mines.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"12 8","pages":"3401-3421"},"PeriodicalIF":3.5,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.1825","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141527459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Analysis of damage mechanisms and controlling factors of fine particle migration in unconsolidated sandstone reservoirs based on reservoir classification 基于储层分类的未固结砂岩储层细颗粒迁移的破坏机制和控制因素分析
IF 3.5 3区 工程技术 Q3 ENERGY & FUELS Pub Date : 2024-06-27 DOI: 10.1002/ese3.1781
Zhao Wang, Hanjun Yin, Haoxuan Tang, Yawei Hou, Hang Yu, Qiang Liu, Hongming Tang

Particle migration in oil and gas reservoirs is a common phenomenon in the process of oil and gas development, and is considered to be an important reason for the damage of reservoir permeability and the reduction of oil and gas productivity. The mechanism of this phenomenon includes the desorption, migration, and precipitation of particles, which eventually clogs the throat and causes reservoir damage. Therefore, it is necessary to accurately characterize the complex mechanism of particle migration and identify the main controlling factors of particle migration, which is very important for efficient oilfield development and plugging solution. First, the reservoir types are divided into three types and the pore structure models of different types of reservoirs are established. Then, computational fluid dynamics and discrete element coupling method numerical simulation and microscopic visualization of pore throat structure model were combined, to characterize the rules of particles and migration, and analyze the main controlling factors. Finally, a typical model of particle migration and clogging is established. The results show that particle size/throat and particle concentration are the key factors affecting particle plugging, and particle migration has the least effect on the permeability of Type I reservoir and the greatest damage to Type III reservoir. According to the mechanical and hydrodynamic behavior of particles in porous media, three mechanisms and six modes of particle plugging are proposed.

油气藏中的颗粒迁移是油气开发过程中的一种常见现象,被认为是造成油气藏渗透率破坏和油气生产率降低的重要原因。这种现象的机理包括颗粒的解吸、迁移和沉淀,最终堵塞喉道,造成储层破坏。因此,有必要准确表征颗粒迁移的复杂机理,找出颗粒迁移的主要控制因素,这对油田高效开发和堵塞解决方案非常重要。首先,将油藏类型分为三种,并建立了不同类型油藏的孔隙结构模型。然后,将计算流体力学和离散元耦合方法数值模拟与孔喉结构模型的微观可视化相结合,表征颗粒及迁移规律,分析主要控制因素。最后,建立了颗粒迁移与堵塞的典型模型。结果表明,颗粒大小/孔喉和颗粒浓度是影响颗粒堵塞的关键因素,颗粒迁移对Ⅰ型储层渗透率影响最小,对Ⅲ型储层破坏最大。根据颗粒在多孔介质中的力学和流体力学行为,提出了颗粒堵塞的三种机理和六种模式。
{"title":"Analysis of damage mechanisms and controlling factors of fine particle migration in unconsolidated sandstone reservoirs based on reservoir classification","authors":"Zhao Wang,&nbsp;Hanjun Yin,&nbsp;Haoxuan Tang,&nbsp;Yawei Hou,&nbsp;Hang Yu,&nbsp;Qiang Liu,&nbsp;Hongming Tang","doi":"10.1002/ese3.1781","DOIUrl":"10.1002/ese3.1781","url":null,"abstract":"<p>Particle migration in oil and gas reservoirs is a common phenomenon in the process of oil and gas development, and is considered to be an important reason for the damage of reservoir permeability and the reduction of oil and gas productivity. The mechanism of this phenomenon includes the desorption, migration, and precipitation of particles, which eventually clogs the throat and causes reservoir damage. Therefore, it is necessary to accurately characterize the complex mechanism of particle migration and identify the main controlling factors of particle migration, which is very important for efficient oilfield development and plugging solution. First, the reservoir types are divided into three types and the pore structure models of different types of reservoirs are established. Then, computational fluid dynamics and discrete element coupling method numerical simulation and microscopic visualization of pore throat structure model were combined, to characterize the rules of particles and migration, and analyze the main controlling factors. Finally, a typical model of particle migration and clogging is established. The results show that particle size/throat and particle concentration are the key factors affecting particle plugging, and particle migration has the least effect on the permeability of Type I reservoir and the greatest damage to Type III reservoir. According to the mechanical and hydrodynamic behavior of particles in porous media, three mechanisms and six modes of particle plugging are proposed.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"12 7","pages":"2879-2898"},"PeriodicalIF":3.5,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.1781","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141508196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Energy conversion efficiency and its improving methods for “Region” solar cell 区域 "太阳能电池的能量转换效率及其改进方法
IF 3.5 3区 工程技术 Q3 ENERGY & FUELS Pub Date : 2024-06-21 DOI: 10.1002/ese3.1817
Isamu Jonoshita

In this paper, a proper noun “Region” is used for nm-scale n-type dopant-rich region in p-type Si crystal. Using this Region, certain solar cells have been assumed. By resonance absorption between photon energy and potential barrier of the Region, the cell can absorb most photons for visible light frequency without passing loss or thermal loss. This light absorption mechanism is different from conventional band gap absorption. Despite this benefit, output voltage is anticipated to decline according to the principle of detail balance. To control the decline, two methods are proposed in this paper. Theoretical energy conversion efficiencies for several cases are calculated with an ideal condition. The calculation result is over 70% as a theoretical value.

本文使用专有名词 "Region "来表示 p 型硅晶体中 nm 级的富含掺杂剂区域。利用该区域,假定了某些太阳能电池。通过光子能量与该区域势垒之间的共振吸收,该电池可以吸收可见光频率的大部分光子,而不会产生传递损耗或热损耗。这种光吸收机制不同于传统的带隙吸收。尽管有这一优点,但根据细节平衡原理,输出电压预计会下降。为了控制电压下降,本文提出了两种方法。在理想条件下,计算了几种情况下的理论能量转换效率。计算结果的理论值超过 70%。
{"title":"Energy conversion efficiency and its improving methods for “Region” solar cell","authors":"Isamu Jonoshita","doi":"10.1002/ese3.1817","DOIUrl":"10.1002/ese3.1817","url":null,"abstract":"<p>In this paper, a proper noun “Region” is used for nm-scale n-type dopant-rich region in p-type Si crystal. Using this Region, certain solar cells have been assumed. By resonance absorption between photon energy and potential barrier of the Region, the cell can absorb most photons for visible light frequency without passing loss or thermal loss. This light absorption mechanism is different from conventional band gap absorption. Despite this benefit, output voltage is anticipated to decline according to the principle of detail balance. To control the decline, two methods are proposed in this paper. Theoretical energy conversion efficiencies for several cases are calculated with an ideal condition. The calculation result is over 70% as a theoretical value.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"12 8","pages":"3327-3340"},"PeriodicalIF":3.5,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.1817","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141527460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Enhancement of the underground cable current capacity by using nano-dielectrics 利用纳米电介质提高地下电缆的载流量
IF 3.5 3区 工程技术 Q3 ENERGY & FUELS Pub Date : 2024-06-21 DOI: 10.1002/ese3.1822
Ossama E. Gouda, Mohamed M. F. Darwish, Ahmed Thabet, Matti Lehtonen, Gomaa F. A. Osman

In most underground power cables, cross-linked polyethylene (XLPE) is utilized as the main insulating material, while polyvinyl chloride (PVC) is usually used as a nonmetallic sheath or jacketing for the cable. Accordingly, improving the electrical and thermal characteristics of these materials leads to an increase in cable dielectric strength, besides a rise in the current capacity of the underground power cables. Thus, enhancing the thermal characteristics of cable insulation is the goal of many research studies. In this regard, increasing the current capacity of underground power cables is an essential topic for electrical distribution and transmission networks. This usually occurs by increasing the cross-sectional area of the cable conductor, which means raising the cost of transmitting electrical energy. Another proposed alternative may be to improve the thermal properties of the dielectric material using nanotechnology to allow better dissipation of heat resulting from the cable losses. This article proposes the use of nano-composite dielectrics to increase the current capacities of underground power cables. Nano-fillers are used to enhance the thermal and electrical characteristics of XLPE and PVC, which represent cable dielectric materials. Accordingly, in this paper, many experiments are conducted on various nano-dielectric materials to choose the most appropriate nano-dielectrics for improving both the thermal and electrical properties. Hence, measurements are performed on the thermal and electrical properties of dielectric nano-materials manufactured in the laboratory. Further, calculations of the cable's current capacities by the use of the measured properties of nano-dielectrics are done considering several backfill soils. From the obtained measurements and calculations carried out on cable capacities, it is concluded that the use of XLPE/ZnO 5 wt.% as the insulation and PVC/ZnO 5 wt.% as the jacket material increased the cable current capacity by 6.2% for a cable of 33 kV rating, 9.2% for 66 kV cable, and 15.7% for 220 kV cable when wet clay is used as backfill soil. From the calculations carried out it is found that the use of nano-composite dielectrics reduces the temperature of the cable components by significant values. For example, the core temperature of the 33 kV cable is reduced by 15.6°C, while for the 66 kV cable, the cable core temperature is decreased by 12.6°C, and for 220 kV the conductor temperature is reduced from 71.3°C to 58.3°C when each cable is loaded by its rating.

在大多数地下电力电缆中,交联聚乙烯(XLPE)被用作主要绝缘材料,而聚氯乙烯(PVC)通常被用作电缆的非金属护套或外套。因此,改善这些材料的电特性和热特性,除了能提高地下电力电缆的电流容量外,还能提高电缆的介电强度。因此,提高电缆绝缘的热特性是许多研究的目标。在这方面,提高地下电力电缆的电流容量是配电和输电网络的一个重要课题。这通常是通过增加电缆导体的横截面积来实现的,这意味着要提高电能传输的成本。另一种建议的替代方法是利用纳米技术改善介电材料的热性能,以便更好地消散电缆损耗产生的热量。本文建议使用纳米复合电介质来提高地下电力电缆的电流容量。纳米填料用于增强代表电缆介电材料的 XLPE 和 PVC 的热特性和电特性。因此,本文对各种纳米电介质材料进行了多次实验,以选择最合适的纳米电介质来改善热性能和电性能。因此,本文对实验室制造的纳米介电材料的热性能和电性能进行了测量。此外,考虑到几种回填土,利用测量到的纳米电介质特性对电缆的电流容量进行了计算。通过对电缆容量的测量和计算得出结论,使用 XLPE/ZnO 5 wt.%作为绝缘材料和 PVC/ZnO 5 wt.%作为护套材料,当使用湿粘土作为回填土时,33 kV 等级电缆的电流容量增加了 6.2%,66 kV 电缆增加了 9.2%,220 kV 电缆增加了 15.7%。通过计算发现,使用纳米复合电介质可显著降低电缆组件的温度。例如,33 千伏电缆的缆芯温度降低了 15.6°C,66 千伏电缆的缆芯温度降低了 12.6°C,220 千伏电缆的导体温度从 71.3°C 降至 58.3°C。
{"title":"Enhancement of the underground cable current capacity by using nano-dielectrics","authors":"Ossama E. Gouda,&nbsp;Mohamed M. F. Darwish,&nbsp;Ahmed Thabet,&nbsp;Matti Lehtonen,&nbsp;Gomaa F. A. Osman","doi":"10.1002/ese3.1822","DOIUrl":"10.1002/ese3.1822","url":null,"abstract":"<p>In most underground power cables, cross-linked polyethylene (XLPE) is utilized as the main insulating material, while polyvinyl chloride (PVC) is usually used as a nonmetallic sheath or jacketing for the cable. Accordingly, improving the electrical and thermal characteristics of these materials leads to an increase in cable dielectric strength, besides a rise in the current capacity of the underground power cables. Thus, enhancing the thermal characteristics of cable insulation is the goal of many research studies. In this regard, increasing the current capacity of underground power cables is an essential topic for electrical distribution and transmission networks. This usually occurs by increasing the cross-sectional area of the cable conductor, which means raising the cost of transmitting electrical energy. Another proposed alternative may be to improve the thermal properties of the dielectric material using nanotechnology to allow better dissipation of heat resulting from the cable losses. This article proposes the use of nano-composite dielectrics to increase the current capacities of underground power cables. Nano-fillers are used to enhance the thermal and electrical characteristics of XLPE and PVC, which represent cable dielectric materials. Accordingly, in this paper, many experiments are conducted on various nano-dielectric materials to choose the most appropriate nano-dielectrics for improving both the thermal and electrical properties. Hence, measurements are performed on the thermal and electrical properties of dielectric nano-materials manufactured in the laboratory. Further, calculations of the cable's current capacities by the use of the measured properties of nano-dielectrics are done considering several backfill soils. From the obtained measurements and calculations carried out on cable capacities, it is concluded that the use of XLPE/ZnO 5 wt.% as the insulation and PVC/ZnO 5 wt.% as the jacket material increased the cable current capacity by 6.2% for a cable of 33 kV rating, 9.2% for 66 kV cable, and 15.7% for 220 kV cable when wet clay is used as backfill soil. From the calculations carried out it is found that the use of nano-composite dielectrics reduces the temperature of the cable components by significant values. For example, the core temperature of the 33 kV cable is reduced by 15.6°C, while for the 66 kV cable, the cable core temperature is decreased by 12.6°C, and for 220 kV the conductor temperature is reduced from 71.3°C to 58.3°C when each cable is loaded by its rating.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"12 9","pages":"3647-3662"},"PeriodicalIF":3.5,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.1822","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141508194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
Energy Science & Engineering
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1