İnşaat Mühendisliği Bölümü Yayın Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/395
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Article Citation - WoS: 4Citation - Scopus: 10Finding the Most Suitable Existing Irrigation Dams for Small Hydropower Development in Turkey: a Gis-Fuzzy Logic Tool(Pergamon-elsevier Science Ltd, 2021) Al Bayat, Omar; Maras, H. Hakan; Kucukali, Serhat; Al Bayatı, OmarThis paper enables a screening of existing irrigation dams in order to assess and rank potential sites for small hydropower development by using a Geographic Information System (GIS)-fuzzy logic multi criteria scoring technique. The following criteria are evaluated: dam characteristics (reservoir normal level, reservoir capacity, dam purpose, dam ageing), and grid connection spatial characteristics. The proposed method estimates the suitability degree of each criterion separately and then aggregates them into a Site Suitability Index (SSI). Existing irrigation dams in Turkey are assessed in order to be utilized for hydropower development. The overall score of each candidate site is obtained and, their performance is compared for different strategies. One of the most suitable dams, Karadere, was chosen as a case study. By using the daily continuous monitored data, we showed that flow and head is highly variable during the irrigation season. Accordingly, we evaluated an innovative compact medium-head hydro turbine that can capture those fluctuations with its operational flexibility and minimal civil works. Moreover, an optimal path methodology was applied to find the best grid connection route from the dam to its nearest substation considering the site land use characteristics in order to minimize land expropriation. (c) 2021 Elsevier Ltd. All rights reserved.Article Citation - WoS: 78Citation - Scopus: 92Finding the Most Suitable Existing Hydropower Reservoirs for the Development of Pumped-Storage Schemes: an Integrated Approach(Pergamon-elsevier Science Ltd, 2014) Kucukali, SerhatThis study aims to evaluate existing hydropower reservoirs for the development of pumped-storage schemes by using multi-criteria scoring technique. This method enables a screening of existing hydropower reservoirs, in order to assess and rank potential sites for pumped-storage development. This analysis is based on the documented evidence, measured data, and site surveys. The site assessments are categorized in 6 criteria namely geometrical conditions (maximum head, head to water way length ratio, distance to grid connection), geological conditions, environmental, and social conditions. In the context of the study, 7 existing hydropower reservoirs in Turkey, each with a catchment area of more than 50 km(2), are evaluated in order to be utilized as the lower reservoirs of pumped-storage facilities. The overall score of each candidate site is obtained and, their performance is compared. The results indicate that Turkey have suitable existing hydropower reservoirs for the development of pumped-storage facilities. However, the country lacks from legal and market framework for the establishment of pumped-storage power plants. (C) 2014 Elsevier Ltd. All rights reserved.Article Citation - WoS: 32Citation - Scopus: 31Wind Energy Resource Assessment of Izmit in the West Black Sea Coastal Region of Turkey(Pergamon-elsevier Science Ltd, 2014) Kucukali, Serhat; Dinckal, CigdemThe wind energy potential of Izmit (41.19 N, 30.30 E), which is located in the West Black Sea Coastal Region of Turkey, is assessed with the statistical analysis of the gathered wind data at the 50-m height measurement mast covering the period of 06/2008-06/2009. The annual average wind speed is calculated as 6 m/s and the prevailing wind direction is ENE (60 degrees). The Weibull distribution parameters of shape and scale factor are found as 2.03 and 6.73 m/s, respectively. The measured wind speed data are compared with the data of nearby meteorological stations and the results show that there is a considerable difference between the onsite measurements and the measurements of the meteorological stations. Moreover, a turbulence analysis is carried out and the turbulence intensity is negatively correlated with the normalized height from ground level with canopy height. The energy generation performances of three different wind turbines are evaluated by using the onsite wind speed measurements and the assessment shows that the capacity factor increase by a factor of two from 17% to 34% depending on the type of the turbine. Furthermore, an economic analysis is carried out for a 50 MW wind energy project for the potential site and the proposed project benefit/cost ratio is calculated as 8. (C) 2013 Elsevier Ltd. All rights reserved.Article Citation - WoS: 110Citation - Scopus: 125Nano-Modification To Improve the Ductility of Cementitious Composites(Pergamon-elsevier Science Ltd, 2015) Yesilmen, Seda; Al-Najjar, Yazin; Balav, Mohammad Hatam; Sahmaran, Mustafa; Yildirim, Gurkan; Lachemi, MohamedEffect of nano-sized mineral additions on ductility of engineered cementitious composites (ECC) containing high volumes of fly ash was investigated at different hydration degrees. Various properties of ECC mixtures with different mineral additions were compared in terms of microstructural properties of matrix, fiber-matrix interface, and fiber surface to assess improvements in ductility. Microstructural characterization was made by measuring pore size distributions through mercury intrusion porosimetry (MIP). Hydration characteristics were assessed using thermogravimetric analysis/differential thermal analysis (TGA/DTA), and fiber-matrix interface and fiber surface characteristics were assessed using scanning electron microscopy (SEM) through a period of 90 days. Moreover, compressive and flexural strength developments were monitored for the same period. Test results confirmed that mineral additions could significantly improve both flexural strength and ductility of ECC, especially at early ages. Cheaper Nano-CaCO3 was more effective compared to nano-silica. However, the crystal structure of CaCO3 played a very important role in the range of expected improvements. (C) 2015 Elsevier Ltd. All rights reserved.Article Citation - WoS: 30Citation - Scopus: 32Risk Scorecard Concept in Wind Energy Projects: an Integrated Approach(Pergamon-elsevier Science Ltd, 2016) Kucukali, SerhatThe proposed risk assessment tool quantifies economic, environmental, political, and societal risks in wind energy projects. The risks are quantified based on the measured data and document evidence. An important component of the proposed methodology includes converting different external risks into a common scale and these scales express the level of risk factors. A survey was conducted with the experts in order to determine the relative importance of external risks. Applicability of the proposed tool is tested on real time wind power plants that are located in Izmir Province on the Aegean coast of Turkey. Change in laws and regulations, environmental issues, local community, grid connection, land use and permits, and erroneous wind resource assessment appeared to be key risk factors. The findings of case studies showed that the perception of inadequate understanding of the potential risks can lead to significant revenue loss. The proposed method estimates each risk factor level separately and then aggregates them by calculating the Project Risk Score (PRS) which is linked to the normalized revenue loss. (C) 2015 Elsevier Ltd. All rights reserved.Article Citation - WoS: 40Citation - Scopus: 45A Fuzzy Logic Tool To Evaluate Low-Head Hydropower Technologies at the Outlet of Wastewater Treatment Plants(Pergamon-elsevier Science Ltd, 2017) Kentel, Elcin; Kucukali, Serhat; Ak, MumtazThis study aims to find the most sustainable mature Low-Head (LH) hydropower technology option to generate hydroelectricity at the outlet of wastewater treatment plants by assessing the relevant economic, technical, and environmental criteria. A total of six criteria are assessed: investment cost, payback period, energy generation performance, construction duration, fish-friendliness, and aeration capacity. The fuzzy logic tool estimates satisfaction of each criterion separately and then aggregates them into an Overall Performance Index. The proposed method is applied to an existing wastewater treatment plant (Tatlar WWTP) in Ankara, Turkey. For the assessment, the real-time operational data of the plant and the technical drawings are employed. According to the multi-criteria analysis tool developed in this study to evaluate the LW technologies' the most appropriate hydropower technology for the outlet of Tatlar WWTP is found to be the Archimedean screw, because of its superior environmental and economic performance.