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Application of solar thermal collectors for energy consumption in public buildings – An updated technical review 太阳能集热器在公共建筑能耗中的应用——最新技术综述
IF 0.9 4区 工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.09.011
Lukman Ahmed Omeiza , Muhammad Abid , Anitha Dhanasekaran , Yathavan Subramanian , Veena Raj , Kateryna Kozak , Ukashat Mamudu , Abul Kalam Azad
The daily energy demand in public buildings has been on the rise, partly due to the intensive use of building energy-comfort technologies. Hot water production, space heating and air-conditioning are the major consumers of energy in public buildings; if their energy demand can be addressed holistically through the integration of solar collectors with public buildings, it will bring about a reduction in energy costs. Fossil fuels, such as coal, oil and gas, are the most significant contributor to global climate change, accounting for over 75% of global greenhouse gas emissions and nearly 90% of all carbon dioxide emissions. Environmental experts are clear, that to avoid the worst impacts of climate change, emissions need to be reduced by almost half by 2030 and reach net-zero by 2050. To meet the global energy demand and minimise environmental hazards, the world needs to reduce its over-reliance on fossil fuels for public building energy consumption and invest in alternative sources of energy that are clean, accessible, affordable, sustainable, and reliable. Our review aims to provide a comprehensive analysis on the various uses of solar thermal collectors in public buildings as a source of green energy supply. The benefits of a potential developed nano-coated absorber surface for solar collectors were studied, and its possible effect on minimising corrosion in heat pipes, absorber surfaces and thermal storage tanks was considered. The merits of using solar collectors, as well as the knowledge gap, limitations, trends and future research prospects are discussed elaborately. Critical attention was paid to recent and past developments in this regard, a technical outlook of various studies is highlighted, and the link between them in addressing the world's over-dependence on fossil fuels is studied.
公共建筑的日常能源需求一直在上升,部分原因是建筑能源舒适技术的大量使用。热水生产、空间供暖和空调是公共建筑的主要能源消耗者;如果他们的能源需求可以通过太阳能集热器与公共建筑的整合来整体解决,它将带来能源成本的降低。煤炭、石油和天然气等化石燃料是导致全球气候变化的最主要因素,占全球温室气体排放量的75%以上,占二氧化碳总排放量的近90%。环境专家明确表示,为了避免气候变化带来的最严重影响,到2030年,排放量需要减少近一半,到2050年达到净零排放。为了满足全球能源需求并最大限度地减少对环境的危害,世界需要减少对公共建筑能源消耗中化石燃料的过度依赖,并投资于清洁、可获得、负担得起、可持续和可靠的替代能源。我们的研究旨在全面分析太阳能集热器作为绿色能源供应来源在公共建筑中的各种用途。研究了一种潜在开发的纳米涂层太阳能集热器表面的好处,并考虑了它对减少热管、吸收器表面和储热罐腐蚀的可能影响。详细讨论了太阳能集热器的优点、知识差距、局限性、发展趋势和未来的研究前景。特别注意了这方面最近和过去的发展,强调了各种研究的技术前景,并研究了它们在解决世界对矿物燃料的过度依赖方面的联系。
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引用次数: 0
Heat management in sonochemical reactor using fins-PCM integrated system: Unveiling the influence of the sonicated volume 利用鳍片-PCM 集成系统在超声化学反应器中进行热量管理:揭示超声体积的影响
IF 0.9 4区 工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2024.01.017
Atef Chibani , Slimane Merouani , Aissa Dehane
With the purpose of enhancing the heat management in the ultrasonic reactor, the present innovative research aims at the exploration of the thermal behavior of sonochemical reactor integrated with fins and phase change material (PCM), focusing on the influence of different liquid heights (LH). The performance of this combination (i.e., sonicated water, fins, and PCM) is investigated for the first time with consideration of the water volume variation. The interplay between fins, liquid height and heat transfer efficiency is explored through detailed numerical analysis of temperature profiles, PCM melt fractions, and enthalpy distributions. The numerical investigation has been conducted using a validated CFD model implemented in ANSYS Fluent® software. The results highlight the significant role of fins in accelerating the PCM melting process and improving heat transfer within the reactor. Notably, fins facilitates efficient conductive heat transfer during the early stages of melting. At t = 1000 s, PCM melt percentages of 22.2 %, 32.6 % and 30 % were attained with fins, compared to 15 %, 18 % and 22 % (without fins), for LH = 5.1, 10.2 and 15.3 cm, respectively. Therefore, LH = 10.2 cm showcased a 43.5 % improvement at this specific time point (1000 s). Moving forward to t = 2000 s, the most favorable melting performance is achieved with LH = 15.3 cm, resulting in a melting percentage increase to 66 % (with fins) compared to 44 % (without fins). Besides, the inclusion of fins results in significant increases of 32.56 % (5.1 cm), 57.6 % (10.2 cm) and 14.4 % (15.3 cm) in PCM enthalpy, while water temperature declined by approximately 4 K for LH = 5.1, 10.2 and 15.3 cm. These outcomes indicate clearly the importance of fins in improving the heat transfer from the irradiated water to the surrounding PCM in the annular space of the reactor.
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引用次数: 0
Dynamic modeling and ride comfort evaluation of railway vehicle under random track irregularities: A case study of a Linke-Hofmann-Busch coach 随机轨道不平整条件下轨道车辆动力学建模及平顺性评价——以林克-霍夫曼-布施客车为例
IF 0.9 4区 工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.08.017
Nitish, Amit Kumar Singh
The ride comfort of passengers is an important parameter for evaluating the performance of railway vehicles. Many standards/ models, such as quarter car, half car, and full car, have been proposed to evaluate the human comfort of railway vehicles. However, a full-scale coupled railway vehicle model is rarely considered for calculating ride comfort. Therefore, this paper proposes a twenty-seven-degree-of-freedom (27-DOF) coupled dynamic model of railway vehicles integrated with wheel-rail contact forces. The developed model is solved using the two-dimensional (2-D) state space method, and the effects of different track irregularities on human comfort are evaluated. The outputs are described in terms of three-dimensional (3-D) Power Spectral Densities (PSDs) under three types of random track irregularities: vertical profile, lateral alignment, and cross-level. Furthermore, Sperling's method is used to evaluate the human comfort index. For the case study, a Linke-Hofmann-Busch coach (LHB) based model has been employed, and the results are validated with the experimental data of ride comfort reported by the Research Design and Standard Organization (RDSO). The simulated results of the proposed model demonstrate a remarkable alignment with the experimental data, exhibiting a small error ranging from 2.36 % to 8.81 % for vertical motion and 5.84 % to 8.30 % for lateral motion, respectively. Such promising results offer valuable insight for the design of future coaches, ensuring enhanced ride comfort even at high speeds.
{"title":"Dynamic modeling and ride comfort evaluation of railway vehicle under random track irregularities: A case study of a Linke-Hofmann-Busch coach","authors":"Nitish,&nbsp;Amit Kumar Singh","doi":"10.1016/j.jer.2023.08.017","DOIUrl":"10.1016/j.jer.2023.08.017","url":null,"abstract":"<div><div>The ride comfort of passengers is an important parameter for evaluating the performance of railway vehicles. Many standards/ models, such as quarter car, half car, and full car, have been proposed to evaluate the human comfort of railway vehicles. However, a full-scale coupled railway vehicle model is rarely considered for calculating ride comfort. Therefore, this paper proposes a twenty-seven-degree-of-freedom (27-DOF) coupled dynamic model of railway vehicles integrated with wheel-rail contact forces. The developed model is solved using the two-dimensional (2-D) state space method, and the effects of different track irregularities on human comfort are evaluated. The outputs are described in terms of three-dimensional (3-D) Power Spectral Densities (PSDs) under three types of random track irregularities: vertical profile, lateral alignment, and cross-level. Furthermore, Sperling's method is used to evaluate the human comfort index. For the case study, a Linke-Hofmann-Busch coach (LHB) based model has been employed, and the results are validated with the experimental data of ride comfort reported by the Research Design and Standard Organization (RDSO). The simulated results of the proposed model demonstrate a remarkable alignment with the experimental data, exhibiting a small error ranging from 2.36 % to 8.81 % for vertical motion and 5.84 % to 8.30 % for lateral motion, respectively. Such promising results offer valuable insight for the design of future coaches, ensuring enhanced ride comfort even at high speeds.</div></div>","PeriodicalId":48803,"journal":{"name":"Journal of Engineering Research","volume":"12 4","pages":"Pages 984-993"},"PeriodicalIF":0.9,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85376527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
A study of a hybrid Fogg-Hook based social media addictive algorithm from the perspective of Kuwait Society 基于混合Fogg-Hook的社交媒体成瘾算法研究——基于科威特社会视角
IF 0.9 4区 工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.09.008
Bader A. Ali, Hanady M. Abdulsalam, Sabah Almadani, Paul Manuel
Social media applications are widely used by human population for general and special purposes. As any emerging computing technology, social media applications’ users tend to heavily use these applications in a way that they can be considered as addicted. Human behavioural studies indicate that a behaviour can be turned into a habit and end with addiction. We study two existing social media addiction algorithms and propose a hybrid algorithm that contains the metrics of both algorithms. We test the validity of our proposed algorithm on Kuwait society through a survey that measures the implementation level of each proposed metric from Kuwait society perspective. We choose four popular social media applications in Kuwait for our tests, namely, Instagram, Twitter, Snapchat, and Tiktok. Our findings confirm the validity of the proposed metrics, and show interesting facts related to the usage level of the social media applications for different groups of Kuwaiti society users, which can be further used in many social media based services in Kuwait.
社交媒体应用程序被人们广泛地用于一般和特殊目的。与任何新兴的计算技术一样,社交媒体应用程序的用户倾向于大量使用这些应用程序,以至于他们可以被认为是上瘾的。人类行为研究表明,一种行为可以变成一种习惯,并以成瘾告终。我们研究了两种现有的社交媒体成瘾算法,并提出了一种包含两种算法指标的混合算法。我们通过一项调查来测试我们提出的科威特社会算法的有效性,该调查从科威特社会的角度衡量每个拟议指标的实施水平。我们在科威特选择了四款流行的社交媒体应用进行测试,分别是Instagram、Twitter、Snapchat和Tiktok。我们的研究结果证实了所提出指标的有效性,并显示了与科威特不同社会用户群体的社交媒体应用程序使用水平相关的有趣事实,这可以进一步用于科威特的许多基于社交媒体的服务。
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引用次数: 0
Utilizing marble and granite industry waste in asphalt mixtures for enhanced road performance and sustainability 利用大理石和花岗岩工业废料在沥青混合物中提高道路性能和可持续性
IF 0.9 4区 工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.10.032
Winícius Rodrigues Pereira de Medeiros , Osires de Medeiros Melo Neto , Priscila Maria Sousa Gonçalves Luz , Ranykelly Kevely Florentino de Oliveira , Leonardo Rodrigues Guedes
Incorporating waste into highway construction has shown to be a promising approach for mitigating environmental impacts and reducing production costs by decreasing the consumption of virgin raw materials. In this context, this study investigated the feasibility of using marble and granite industry waste as a partial and total substitute for filler in hot asphalt mixtures. Physical analyses of the constituents were carried out, and the asphalt mixtures were designed using the SUPERPAVE methodology. The filler content obtained was 2 % for the upper gradation curve determined during the dosage process. Subsequently, the marble and granite residue was added in proportions of 50 % and 100 % by weight, replacing the commonly used filler, hydrated lime. The asphalt mixtures were evaluated for their mechanical performance through tests for tensile strength and resilient modulus. The data obtained were subjected to statistical analysis using the Student's t-test with a significance level of 5 %. The results indicated that asphalt mixtures with marble and granite waste exhibited slightly superior mechanical performance compared to the control mixture (with 0 % residue). The statistical test revealed no significant differences between the mixtures for the conducted tests. Additionally, the production costs per ton and per kilometer of highway were practically the same for all three types of evaluated mixtures. In conclusion, the addition of marble and granite industry waste as filler, both partially and entirely, is feasible from both technical and economic perspectives, as it demonstrated equivalent performance to the control mixture. This approach also represents a means to minimize environmental impacts by reducing the demand for raw materials (hydrated lime) and contributing to the proper disposal of waste generated by the ornamental rocks industry.
{"title":"Utilizing marble and granite industry waste in asphalt mixtures for enhanced road performance and sustainability","authors":"Winícius Rodrigues Pereira de Medeiros ,&nbsp;Osires de Medeiros Melo Neto ,&nbsp;Priscila Maria Sousa Gonçalves Luz ,&nbsp;Ranykelly Kevely Florentino de Oliveira ,&nbsp;Leonardo Rodrigues Guedes","doi":"10.1016/j.jer.2023.10.032","DOIUrl":"10.1016/j.jer.2023.10.032","url":null,"abstract":"<div><div>Incorporating waste into highway construction has shown to be a promising approach for mitigating environmental impacts and reducing production costs by decreasing the consumption of virgin raw materials. In this context, this study investigated the feasibility of using marble and granite industry waste as a partial and total substitute for filler in hot asphalt mixtures. Physical analyses of the constituents were carried out, and the asphalt mixtures were designed using the SUPERPAVE methodology. The filler content obtained was 2 % for the upper gradation curve determined during the dosage process. Subsequently, the marble and granite residue was added in proportions of 50 % and 100 % by weight, replacing the commonly used filler, hydrated lime. The asphalt mixtures were evaluated for their mechanical performance through tests for tensile strength and resilient modulus. The data obtained were subjected to statistical analysis using the Student's t-test with a significance level of 5 %. The results indicated that asphalt mixtures with marble and granite waste exhibited slightly superior mechanical performance compared to the control mixture (with 0 % residue). The statistical test revealed no significant differences between the mixtures for the conducted tests. Additionally, the production costs per ton and per kilometer of highway were practically the same for all three types of evaluated mixtures. In conclusion, the addition of marble and granite industry waste as filler, both partially and entirely, is feasible from both technical and economic perspectives, as it demonstrated equivalent performance to the control mixture. This approach also represents a means to minimize environmental impacts by reducing the demand for raw materials (hydrated lime) and contributing to the proper disposal of waste generated by the ornamental rocks industry.</div></div>","PeriodicalId":48803,"journal":{"name":"Journal of Engineering Research","volume":"12 4","pages":"Pages 670-679"},"PeriodicalIF":0.9,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136152689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
Comparing time and cost performance of DBB and DB public construction projects in Kuwait 比较科威特 DBB 和 DB 公共建筑项目的时间和成本绩效
IF 0.9 4区 工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.11.016
Sarah Soud Salem Al-enezi, Ruqaya Al Sabah
Kuwait is an enormous construction site as many vital public projects are under construction or in preparatory stages to achieve the vision of a New Kuwait by 2035. However, the new Public Tenders Law No. 49 of 2016 authorized the sole operation of the Design-Bid-Build (DBB) method as the delivery system method, preventing the employment of Design-Build (DB). Hence, this research undertook a comparative analysis of cost and time performance of DBB and DB public construction projects in Kuwait for the first time, marking the originality of this study. Moreover, 160 projects were collected from four government entities. Then, the total collected projects were categorized based on contract types and project sizes depending on contract cost. This research has recognized that DB has superior performance compared to DBB regarding cost growth for all collected projects, both contract types, projects of less than 300,000 KD, and projects between 300,000 and 12 million KD. No statistically significant differences between DBB and DB projects regarding schedule growth were found for all collected projects, both contract types and project sizes. Furthermore, the findings indicated that the DBB projects’ construction intensity was faster than that of DB projects with a value between 300,00 KD and 12 million KD. For projects that had a value of more than 12 million KD, the DB projects’ construction intensity was faster than that of DBB projects. Hence, it is concluded that the issue is not with the DB delivery systems themselves, but rather with the deployment of these systems.
{"title":"Comparing time and cost performance of DBB and DB public construction projects in Kuwait","authors":"Sarah Soud Salem Al-enezi,&nbsp;Ruqaya Al Sabah","doi":"10.1016/j.jer.2023.11.016","DOIUrl":"10.1016/j.jer.2023.11.016","url":null,"abstract":"<div><div>Kuwait is an enormous construction site as many vital public projects are under construction or in preparatory stages to achieve the vision of a New Kuwait by 2035. However, the new Public Tenders Law No. 49 of 2016 authorized the sole operation of the Design-Bid-Build (DBB) method as the delivery system method, preventing the employment of Design-Build (DB). Hence, this research undertook a comparative analysis of cost and time performance of DBB and DB public construction projects in Kuwait for the first time, marking the originality of this study. Moreover, 160 projects were collected from four government entities. Then, the total collected projects were categorized based on contract types and project sizes depending on contract cost. This research has recognized that DB has superior performance compared to DBB regarding cost growth for all collected projects, both contract types, projects of less than 300,000 KD, and projects between 300,000 and 12 million KD. No statistically significant differences between DBB and DB projects regarding schedule growth were found for all collected projects, both contract types and project sizes. Furthermore, the findings indicated that the DBB projects’ construction intensity was faster than that of DB projects with a value between 300,00 KD and 12 million KD. For projects that had a value of more than 12 million KD, the DB projects’ construction intensity was faster than that of DBB projects. Hence, it is concluded that the issue is not with the DB delivery systems themselves, but rather with the deployment of these systems.</div></div>","PeriodicalId":48803,"journal":{"name":"Journal of Engineering Research","volume":"12 4","pages":"Pages 680-690"},"PeriodicalIF":0.9,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139292549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
Performance evaluation of turbulent circular heat exchanger with a novel flow deflector-type baffle plate 新型折流板型紊流循环换热器的性能评价
IF 0.9 4区 工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.100105
Md Atiqur Rahman, Sushil Kumar Dhiman
Experiments were conducted to investigate the performance of an axial flow tubular heat exchanger with a novel swirl flow of air created by the addition of circular baffle plates featuring trapezoidal air deflectors with various inclination angles. The tubes remained in identical longitudinal arrangement and maintained constant heat flux over their surface. Each baffle plate contained four deflectors with an equal inclination angle, generating an air swirl inside the circular duct containing the heated tubes that improved the air-side turbulence and thus the rate of heat transfer from the tubes' surfaces. The pitch ratio of the baffle plates was varied, and the Reynolds number was kept in the range of 16000–28000. Results from the study showed an average 7.4% improvement in performance enhancement criteria when the exchanger was fitted with a baffle plate featuring a deflector inclination angle of 30° and operated under counter flow conditions when compared to a parallel flow arrangement operating under similar experimental conditions.
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引用次数: 0
Thermal image identification against pose and expression variations using deep learning 基于深度学习的姿态和表情变化的热图像识别
IF 0.9 4区 工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.10.043
Naser Zaeri , Rusul Qasim
Thermal infrared face recognition systems have developed as an effective complement to visual systems for biometric identity purposes and military operations. With the help of deep learning and convolutional neural networks, we provide an efficient approach for thermal facial identification that can handle position fluctuations and expression dissimilarities in this study. As an essential deep learning model that has demonstrated its effectiveness in several computer vision and machine learning applications, we employ the ResNet-50 architecture which consists of 50 layers of convolution, activation, and pooling. The structures of those layers are discussed in detail to gain a profound insight about the operation of this architecture. In this regard, a deep and detailed mathematical analysis is furnished. The system is implemented on a dataset of 1500 thermal images, where we execute experiments in various setups and circumstances to address the issues with posture and expression variance. The experimental results show that the system achieves an accuracy rate of 99.4% when it is trained using 30% of the dataset after five epochs. With respect to other performance measures, the system attains 100% recall, precision, F-score, and specificity. In comparison to recently published works, the findings show that the suggested system offers improved discriminability, resilience against fluctuations, as well as high identification rates under diverse settings that mimic real-world scenarios.
热红外人脸识别系统已经发展成为生物识别目的和军事行动视觉系统的有效补充。在本研究中,我们利用深度学习和卷积神经网络提供了一种有效的热人脸识别方法,可以处理位置波动和表情差异。作为一种重要的深度学习模型,它已经在几个计算机视觉和机器学习应用中证明了它的有效性,我们采用了由50层卷积、激活和池化组成的ResNet-50架构。我们将详细讨论这些层的结构,以深入了解该体系结构的操作。在这方面,提供了深入而详细的数学分析。该系统在1500张热图像的数据集上实现,我们在各种设置和环境下执行实验,以解决姿势和表情差异的问题。实验结果表明,在使用30%的数据集进行5次epoch训练时,系统的准确率达到了99.4%。相对于其他性能指标,该系统达到100%的召回率、精确度、f值和特异性。与最近发表的研究成果相比,研究结果表明,所建议的系统具有更好的可辨别性、抗波动能力,以及在模拟现实世界场景的不同设置下的高识别率。
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引用次数: 0
An optimum design and economic feasibility analysis of wind farms in Kuwait using different wind generation technologies 科威特使用不同风力发电技术的风电场的优化设计和经济可行性分析
IF 0.9 4区 工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.10.028
Rashad M. Kamel, Mohamed El Badawi, Sultan Sh. Alanzi
Kuwait plans to produce 15 % of its electricity from renewable resources by 2030. This paper aims at designing a 300-MW wind farm in six different sites in Kuwait. The study uses the measured wind data at Kuwait International Airport to predict the wind profile (speed and power density) at the selected sites. To validate the work, two different types of wind generation technologies are used in the design. The first type is Full-Converter Wind Turbine Generators (FCWTGs), and the second type is Doubly Fed Induction Generators (DFIGs). The designed wind farms are simulated using the Wind Atlas Analysis and Application Program (WAsP®) to estimate the Annual Energy Production (AEP) for each type of wind farms in each selected site. The location of every wind turbine in each wind farm (both types) for every selected site is accurately determined while considering needed spacing between rows and columns of turbines. The wake effect for downstream wind turbines is considered and estimated in the design. A comparison between the different wind farms in the six sites using the DIFGs and the FCWTGs generators is carried out. The economic feasibility of the designed wind farms is studied using the estimated Annual Energy Production (AEP) in each one of the designed wind farms.
科威特计划到2030年利用可再生资源生产15%的电力。本文旨在在科威特的六个不同地点设计一个300兆瓦的风力发电场。该研究使用在科威特国际机场测量的风数据来预测选定地点的风廓线(速度和功率密度)。为了验证这项工作,设计中使用了两种不同类型的风力发电技术。第一种是全变换器风力发电机(FCWTGs),第二种是双馈感应发电机(DFIGs)。使用风图集分析和应用程序(WAsP®)对设计的风电场进行模拟,以估计每个选定地点每种类型风电场的年发电量(AEP)。每个选定地点的每个风电场(两种类型)的每个风力涡轮机的位置在考虑涡轮机的行和列之间所需的间距时精确确定。在设计中考虑并估计了下游风力机的尾流效应。对使用difg和FCWTGs发电机的六个地点的不同风电场进行了比较。利用各设计风电场的年发电量(AEP)估算值,研究了设计风电场的经济可行性。
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引用次数: 0
Development of an economic smart aquaponic system based on IoT 基于物联网的经济型智能水培系统开发
IF 0.9 4区 工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY Pub Date : 2024-12-01 DOI: 10.1016/j.jer.2023.08.024
M.M.M. Mahmoud , Rania Darwish , A.M. Bassiuny
Aquaponics is a sustainable farming practice that combines aquaculture and hydroponics in a recirculating system. The nutrients from the fish waste are used by the plants to grow, and the plants filter the water for the fish. This process is self-sustaining and requires little human intervention. The monitoring and control of aquaponic systems is a complex task. In this research, the Internet of Things (IoT) is utilized to monitor and control the proposed system. In addition, a digital twin (DT) is deployed to digitize the physical system. The results explore that IoT and DT can improve aquaponic systems by collecting data about environmental conditions that is used to regulate plant growth, monitor fish health, optimize crop production, and optimize nutrient recycling. This decreased the need for and cost of human monitoring and improved the system's economics.
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引用次数: 0
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