Yazar "Tantekin, Atakan" seçeneğine göre listele
Listeleniyor 1 - 17 / 17
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Energy Analysis in a Solar House with Building-Integrated Photovoltaic (BIPV) System(2022) Tantekin, Atakan; Ozdıl, Naime FilizIncreased energy demand and fossil fuel usage of the world has led to the search for new and clean energy production methods. Renewable energy sources are developing and emerging options for energy production methods. Sun is the most accessible and stable renewable energy source. There are several methods to produce energy from the sun. The building-integrated photovoltaic (BIPV) system is a well-known method for generating electricity by using solar cells to transform the energy from the sun into electricity. BIPVs are a new technique to reduce energy consumption from fossil fuels. Passive solar houses mean that the energy demand of the living space is met with the usage of solar energy for the heating and cooling demand of the living space. In this study, an existing house, located in Istanbul, is modeled and covered with photovoltaics with the help of a computer program and the amount of energy produced with the aid of these photovoltaics is presented. The analysis demonstrates that the yearly average amount of daily electricity production is varied between 1.05 kWh as the minimum value and 19.7 kWh as the maximum value for all facades. The yearly average amount of monthly electricity production is varied between 31.8 kWh as the minimum value and 599 kWh as the maximum value for all facades.Öğe Energy and exergy analyses of a fluidized bed coal combustor steam plant in textile industry(Elsevier Sci Ltd, 2016) Ozdil, N. Filiz Tumen; Tantekin, Atakan; Erbay, ZaferIn this study, the analyses of first and second laws of thermodynamic are presented for a 6.5 MW power plant located in Adana, Turkey. The system components, examined in the present study, are listed as a fluidized bed coal combustor (FBCC), a heat recovery steam generator (HRSG), an economizer (ECO), fans, pumps, a cyclone and a chimney. All of the system components are examined one by one and the energy and exergy analyses are carried out for all of the system components. The highest value of irreversibility is observed in the FBCC, about 93% of the entire system irreversibility tracked by HRSG and ECO with 3% and 1%, respectively. The high excess air value, which is the primary origin of irreversibility, causes the heat losses from the FBCC, due to the increment in mass flow rate of the combustion gas. Moreover, the high excess air value gives rise to occurrence of low combustion efficiency in FBCC which can be decreased through decreasing flow rate of air with decreasing oxygen. Secondly, changes in the energy and exergy efficiencies are examined employing different ambient temperature. As the ambient temperature increases, the second law efficiencies of FBCC and HRSG increases but efficiency of ECO decreases. (C) 2016 Elsevier Ltd. All rights reserved.Öğe EXERGOECONOMIC ANALYSIS OF A FLUIDIZED BED COAL COMBUSTION STEAM POWER PLANT(Vinca Inst Nuclear Sci, 2017) Tumen Ozdil, N. Filiz; Tantekin, AtakanIn this study, extensive exergoeconomic analysis is performed for a 6.5 MW steam power plant using the data obtained from running system. The role and impact of the each system component on the first and second law efficiencies are analyzed to understand the individual performance of sub-components. Moreover, the quantitative exergy cost balance for each component is considered to point out the exergoeconomic performance. The analysis shows that the largest irreversibility occurs in the fluidized bed coal combustion (FBCC), about 93% of the overall system irreversibility. Furthermore, it is followed by heat recovery steam generator and economizer with 3% and 1%, respectively. In this study, the capital investment cost, operating and maintenance costs and total cost of FBCC steam plant are calculated as 6.30, 5.35, and 11.65 US$ per hour, respectively. The unit exergy cost and fuel exergy cost, which enter the FBCC steam plant, are found as 3.33 US$/GJ and 112.44 US$/h, respectively. The unit exergy cost and exergy cost of the steam which is produced in heat recovery steam generator are calculated as 16.59 US$/GJ and 91.87 US$ per hour, respectively. This study emphasizes the importance of the exergoeconomic analysis based on the results obtained from the exergy analysis.Öğe Exergy and exergoeconomic analyses of a fluidized bed coal combustion steam plant in textile industry(Adana Alparslan Türkeş Bilim ve Teknoloji Üniversitesi, 2017) Tantekin, Atakan; Özdil, Naime FilizBu çalışmada, termodinamiğin birinci ve ikinci kanunlarının analizi, Adana'da bulunan 6.5 MW'lık bir santral için sunulmuştur. Bu çalışmada incelenen sistem bileşenleri, akışkan yataklı kömür kazanı, bir ısı geri kazanımlı buhar jeneratörü, ekonomizer, fanlar, pompalar, siklon ve baca olarak sayılır. Tüm sistem bileşenleri tek tek incelenmiş olup tüm sistem bileşenleri için enerji ve ekserji analizleri gerçekleştirilmiştir. Analiz sonucunda, tersinmezliğin en yüksek değeri %93 ile akışkan yataklı kömür kazanında ve %3 ve %1 ile sırasıyla ısı geri kazanımlı buhar jeneratöründe ve ekonomizerde gözlemlenmiştir. Tersinmezliğin başlıca kaynağı olan aşırı hava değeri, yanma gazının kütle akış hızındaki artış nedeniyle akışkan yataklı kömür kazanındaki ısı kayıplarına neden olur. Ayrıca, aşırı hava değeri, akışkan yataklı kömür kazanında düşük yanma verimliliğine neden olur ki bu aşırı hava değeri havanın akış hızını azaltarak azaltılabilir. Buna ek olarak, her bir bileşenin eksergoekonomik performansını ortaya koymak için, ekserji dengesinin nicel maliyeti göz önüne alınmıştır. Sermaye yatırım maliyeti, işletme ve bakım maliyeti ve buhar santralinin toplam maliyeti sırasıyla 6.30, 5.35 ve 11.65 US$/h olarak elde edilmiştir. Buhar santraline giren birim ekserji maliyeti ve yakıt ekserji maliyeti sırasıyla 3.33 US$/GJ ve 112.44 US$/h olarak bulunmuştur. Isı geri kazanımlı buhar jeneratöründe üretilen buharın birim ekserji maliyeti ve ekserji maliyeti, sırasıyla 16.59 US$/GJ ve 91.87 US$/h olarak hesaplanmıştır. Bu çalışma, eksergoekonomik analizin ekserji analizinden elde edilen sonuçlarla bağlantılı olarak önemini vurgulamaktadır.Öğe Exergy and exergoeconomic assessments of an electricity production system in a running wastewater treatment plant(Pergamon-Elsevier Science Ltd, 2016) Ozdil, N. Filiz Tumen; Tantekin, AtakanThis study aims at presenting a detailed exergy and exergoeconomic analyses of a biogas engine powered electricity production system in a wastewater treatment plant located in Adana, Turkey. The overall system consists of a compressor, a turbine, a pump, four heat exchangers and a gas engine. The effect of the each system component on the exergy efficiency and exergoeconomic parameters is analyzed separately. The analysis indicates that major exergy destruction happens in the gas engine as 4055.31 kW, followed by the exhaust gas heat exchanger (EGHE) and lubrication oil heat exchanger (LOHE) as 99.86 kW and 92.64 kW, respectively. The second law efficiency of the compressor, turbine, pump, BGHE, LOHE, WHE, EGHE and gas engine are found as 76.50%, 78.43%, 6.49%, 13.40%, 11.56%, 60.44%, 67.36%, and 50.79%, respectively. The operating and maintenance costs, capital investment cost and total cost of the system are reckoned as 14.74 US$/h, 13.90 US$/h, and 28.64 US$/h, respectively to point out the exergoeconomic performance. The unit exergy cost and exergy cost of the fuel, which feeds the compressor, are reckoned as 4.88 US$/GJ and 141.12 US$/h. The exergy cost and electricity production unit exergy cost in the turbine are found as 4.87 US$/h and 11.32 US$/GJ. (C) 2016 Elsevier Ltd. All rights reserved.Öğe Exergy and exergoeconomic assessments of an electricity production system in a running wastewater treatment plant(Pergamon-Elsevier Science Ltd, 2016) Ozdil, N. Filiz Tumen; Tantekin, AtakanThis study aims at presenting a detailed exergy and exergoeconomic analyses of a biogas engine powered electricity production system in a wastewater treatment plant located in Adana, Turkey. The overall system consists of a compressor, a turbine, a pump, four heat exchangers and a gas engine. The effect of the each system component on the exergy efficiency and exergoeconomic parameters is analyzed separately. The analysis indicates that major exergy destruction happens in the gas engine as 4055.31 kW, followed by the exhaust gas heat exchanger (EGHE) and lubrication oil heat exchanger (LOHE) as 99.86 kW and 92.64 kW, respectively. The second law efficiency of the compressor, turbine, pump, BGHE, LOHE, WHE, EGHE and gas engine are found as 76.50%, 78.43%, 6.49%, 13.40%, 11.56%, 60.44%, 67.36%, and 50.79%, respectively. The operating and maintenance costs, capital investment cost and total cost of the system are reckoned as 14.74 US$/h, 13.90 US$/h, and 28.64 US$/h, respectively to point out the exergoeconomic performance. The unit exergy cost and exergy cost of the fuel, which feeds the compressor, are reckoned as 4.88 US$/GJ and 141.12 US$/h. The exergy cost and electricity production unit exergy cost in the turbine are found as 4.87 US$/h and 11.32 US$/GJ. (C) 2016 Elsevier Ltd. All rights reserved.Öğe Experimental and Numerical Investigation of Flow Characteristics Around Complex Bridge Piers in Different Geometries(Taylor & Francis Ltd, 2023) Tantekin, Atakan; Tumen Ozdil, N. Filiz; Akilli, HueseyinThe flow parameters through complex-type bridge piers configured in various geometries were explored and compared in this work using dye visualisation and computational fluid dynamics (CFD) methods. The Detached Eddy Simulation (DES) technique based on the SST k omega model has been chosen to investigate the flow characteristics around complex bridge piers, and time-averaged normalised mean streamwise velocity, time-averaged normalised mean cross-stream velocity, time-averaged normalised mean pressure, time-averaged normalised mean Reynolds shear stress, time-averaged normalised mean y vorticity, time-averaged normalised mean z vorticity, and drag coefficient have been selected as parameters for this study. According to the study's findings, when the time-averaged normalised mean streamwise velocity component of all complex bridge piers was examined, the pile sections had the highest values. Drag coefficients have been sorted from low to high when comparing complex bridge piers in all geometries such as elliptical, circular, rectangular, and square.Article Highlights Flow characteristics around complex bridge piersDye visualisation experiments and CFD method with DES based on the SST k omega modelDrag Coefficients of complex bridge piersÖğe Experimental and Numerical Investigation of Flow Characteristics Around Complex Bridge Piers in Different Geometries(Taylor & Francis Ltd, 2023) Tantekin, Atakan; Tumen Ozdil, N. Filiz; Akilli, HueseyinThe flow parameters through complex-type bridge piers configured in various geometries were explored and compared in this work using dye visualisation and computational fluid dynamics (CFD) methods. The Detached Eddy Simulation (DES) technique based on the SST k omega model has been chosen to investigate the flow characteristics around complex bridge piers, and time-averaged normalised mean streamwise velocity, time-averaged normalised mean cross-stream velocity, time-averaged normalised mean pressure, time-averaged normalised mean Reynolds shear stress, time-averaged normalised mean y vorticity, time-averaged normalised mean z vorticity, and drag coefficient have been selected as parameters for this study. According to the study's findings, when the time-averaged normalised mean streamwise velocity component of all complex bridge piers was examined, the pile sections had the highest values. Drag coefficients have been sorted from low to high when comparing complex bridge piers in all geometries such as elliptical, circular, rectangular, and square.Article Highlights Flow characteristics around complex bridge piersDye visualisation experiments and CFD method with DES based on the SST k omega modelDrag Coefficients of complex bridge piersÖğe Flow investigation of circular cylinder having different cavities in shallow water(Elsevier Science Inc, 2021) Tantekin, Atakan; Ozdil, N. Filiz Tumen; Akilli, Huseyin; Caliskan, MeltemThe control of the unsteady flow structure formed behind a cylinder placed horizontally in shallow water was analyzed experimentally using bare cylinder and cylinders with cavities having square and rectangular geometries, respectively. Reynolds number, Froude number and water height had been chosen as 5000, 0.27 and 90 mm, respectively and also these parameters were kept constant for all experiments. To consider the influence of height (h), the cylinder level was located at various heights from h: 0 mm to 60 mm. Furthermore, cavity angle (a) had been selected from 0 degrees, 80 degrees, 85 degrees, 90 degrees and 95 degrees to consider influence of cavity angle on flow. With the help of Particle Image Velocimetry (PIV), average velocity vectors were measured in two dimensions at many points simultaneously in a planar flow area. The results uncovered that large negative counter was observed at h: 37.5 mm in bare cylinder as well as cylinders having square and rectangular cavities at h: 45 mm. Also, no negative counter was observed for cylinders having rectangular cavity at h: 0 mm and a: 90 degrees and 95 degrees due to the bottom effect. Due to surface effects, a foci point was formed in all cylinders where close to the surface and close to the base. Two foci points and a saddle point were seen as they moved away from the surface for all cylinders. Also, the smallest vortex region was observed for cylinders having rectangular cavity at h: 37.5 mm and a: 90 degrees and 95 degrees in whole cylinders. Also, the highest drag coefficient (Cd) value was obtained for cylinder having square cavity at h: 52.5 mm and a: 80 degrees while the highest drag coefficient value was obtained for cylinder having rectangular cavity at h: 37.5 mm and a: 95 degrees.Öğe Investigation of Different Working Fluid Effectson Exergy Analysis for Organic Rankine Cycle (ORC)(2016) Tümen, N.Filiz Özdil; Tantekin, Atakan; Seğmen, M.RıdvanBu çalışmada, Türkiye'nin güneyinde bulunan bir yerel güç santralindeki Organik Rankine Çevrimi için ekserji analizi yapılmıştır. Organik Rankine Çevrimi, düşük sıcaklıktaki ısı kaynağı için farklı organik soğutucu akışkanlar ile ısı geri kazanım işlemi olarak kullanılır. İncelenen sistem evaporatör, türbin, kondenser, pompa ve jeneratör bölümlerinden oluşmaktadır. Değerlendirme, her sistem bileşenine iki farklı soğutucu akışkan için yapılmıştır. Bu çalışmanın temel amacı,Organik Rankine Çevriminin performans optimizasyonunu sağlamak üzere iki farklı soğutucu akışkanınilgili sıcaklık aralıklarında kullanılarak modellenmesidir. Soğutucu akışkanların Organik Rankine Çevriminin performansı üzerine etkisini göstermek amacıyla HFE7100 ve FC72 akışkanları performans parametresi olarak seçilmiştirÖğe Investigation of flow characteristics for triangular grooved shape cylinder at different heights in shallow water(Pergamon-Elsevier Science Ltd, 2021) Caliskan, Meltem; Tantekin, Atakan; Ozdil, N. Filiz Tumen; Akilli, HuseyinThis study is an investigation and comparison of the flow characteristic around triangular grooved and bare cylinders, positioned horizontally in shallow water using Particle Image Velocimetry (PIV). Throughout the experiment, Reynolds number, Froude number and water height have been selected as 5000, 0.27 and 90 mm, respectively. To observe the effect of height (h) on the flow structure, cylinder is positioned at h: 0 mm, 15 mm, 22.5 mm, 30 mm, 37.5 mm, 45 mm, 52.5 mm and 60 mm. Moreover, grooved angle (a) has been changed from 0 degrees, 80 degrees, 85 degrees, 90 degrees and 95 degrees in shallow water to investigate the effect of grooved angle. The results show that the vortex forms vary according to the groove angle. It is seen that the vortex, the cylinders especially positioned at h: 0 mm and h: 60 mm, are affected owing to the surface and bottom effect. Furthermore, the largest Reynolds stress is observed at the h: 37.5 mm while the largest wake region is observed at the h: 52.5 mm. Also, the maximum Drag Coefficient (C-d) and Turbulence Kinetic Energy (TKE) are observed at h: 0 mm, a: 90 degrees for grooved cylinder and at h: 37.5 mm for bare cylinder, respectively.Öğe The investigation of the applicability of data-driven techniques in hydrological modeling: The case of seyhan basin(Middle Pomeranian Scientific Society of The Environment Protection, 2019) Turhan, Evren; Keleş, Mümine Kaya; Tantekin, Atakan; Keleş, Abdullah EmreProper water resources planning and management is based on reliable hydrological data. Missing rainfall and runoff observation data, in particular, can cause serious risks in the planning of hydraulics structures. Hydrological modeling process is quitely complex. Therefore, using alternative estimation techniques to forecast missing data is reasonable. In this study, two data-driven techniques such as Artificial Neural Networks (ANN) and Data Mining were investigated in terms of availability in hydrology works. Feed Forward Back Propagation (FFBPNN) and Generalized Regression Neural Networks (GRNN) methods were performed on rainfall-runoff modeling for ANN. Besides, Hydrological drought analysis were examined using data mining technique. The Seyhan Basin was preferred to carry out these techniques. It is thought that the application of different techniques in the same basin could make a great contribute to the present work. Consequently, it is seen that FFBPNN is the best model for ANN in terms of giving the highest R2 and lowest MSE values. Multilayer Perceptron (MLP) algorithm was used to predict the drought type according to limit values. This system has been applied to show the relationship between hydrological data and measure the prediction accuracy of the drought analysis. According to the obtained data mining results, MLP algorithm gives the best accuracy results as flow observation stations using SRI-3 month data. © 2019, Middle Pomeranian Scientific Society of The Environment Protection. All rights reserved.Öğe The Investigation of the Applicability of Data-Driven Techniques in Hydrological Modeling: The Case of Seyhan Basin(Middle Pomeranian Sci Soc Env Prot, 2019) Turhan, Evren; Keles, Mumine Kaya; Tantekin, Atakan; Keles, Abdullah EmreProper water resources planning and management is based on reliable hydrological data. Missing rainfall and runoff observation data, in particular, can cause serious risks in the planning of hydraulics structures. Hydrological modeling process is quitely complex. Therefore, using alternative estimation techniques to forecast missing data is reasonable. In this study, two data-driven techniques such as Artificial Neural Networks (ANN) and Data Mining were investigated in terms of availability in hydrology works. Feed Forward Back Propagation (FFBPNN) and Generalized Regression Neural Networks (GRNN) methods were performed on rainfall-runoff modeling for ANN. Besides, Hydrological drought analysis were examined using data mining technique. The Seyhan Basin was preferred to carry out these techniques. It is thought that the application of different techniques in the same basin could make a great contribute to the present work. Consequently, it is seen that FFBPNN is the best model for ANN in terms of giving the highest R2 and lowest MSE values. Multilayer Perceptron (MLP) algorithm was used to predict the drought type according to limit values. This system has been applied to show the relationship between hydrological data and measure the prediction accuracy of the drought analysis. According to the obtained data mining results, MLP algorithm gives the best accuracy results as flow observation stations using SRI-3 month data.Öğe The Investigation of the Applicability of Data-Driven Techniques in Hydrological Modeling: The Case of Seyhan Basin(Middle Pomeranian Sci Soc Env Prot, 2019) Turhan, Evren; Keles, Mumine Kaya; Tantekin, Atakan; Keles, Abdullah EmreProper water resources planning and management is based on reliable hydrological data. Missing rainfall and runoff observation data, in particular, can cause serious risks in the planning of hydraulics structures. Hydrological modeling process is quitely complex. Therefore, using alternative estimation techniques to forecast missing data is reasonable. In this study, two data-driven techniques such as Artificial Neural Networks (ANN) and Data Mining were investigated in terms of availability in hydrology works. Feed Forward Back Propagation (FFBPNN) and Generalized Regression Neural Networks (GRNN) methods were performed on rainfall-runoff modeling for ANN. Besides, Hydrological drought analysis were examined using data mining technique. The Seyhan Basin was preferred to carry out these techniques. It is thought that the application of different techniques in the same basin could make a great contribute to the present work. Consequently, it is seen that FFBPNN is the best model for ANN in terms of giving the highest R2 and lowest MSE values. Multilayer Perceptron (MLP) algorithm was used to predict the drought type according to limit values. This system has been applied to show the relationship between hydrological data and measure the prediction accuracy of the drought analysis. According to the obtained data mining results, MLP algorithm gives the best accuracy results as flow observation stations using SRI-3 month data.Öğe Thermodynamic analysis of an Organic Rankine Cycle (ORC) based on industrial data(Pergamon-Elsevier Science Ltd, 2015) Ozdil, N. Filiz Tumen; Segmen, M. Ridvan; Tantekin, AtakanIn this study, thermodynamic analysis of an Organic Rankine Cycle (ORC) is presented in a local power plant that is located southern of Turkey. The system that is analyzed includes an evaporator, a turbine, a condenser, a pump and a generator as components. System components are analyzed separately using actual plant data and performance cycle. The relationship between pinch point and exergy efficiency is observed. As the pinch point temperature decreases, the exergy efficiency increases due to low exergy destruction rate. The energy and exergy efficiencies of the ORC are calculated as 9.96% and 47.22%, respectively for saturated liquid form which is the real condition. In order to show the effect of the water phase of the evaporator inlet, exergy destruction and exergy efficiencies of components and overall system are calculated for different water phases. The exergy efficiency of the ORC is calculated as 41.04% for water mixture form which has quality 0.3. On the other hand, it is found as 40.29% for water mixture form which has quality 0.7. Lastly, it is calculated as 39.95% for saturated vapor form. Moreover, exergy destruction rates of the system are 520.01 kW for saturated liquid form, 598.39 kW for water mixture form which has quality 0.3, 609.5 kW for water mixture form which has quality 0.7 and 614.63 kW for saturated vapor form. The analyses show that evaporator has important effect on the system efficiency in terms of exergy rate. The evaporator is investigated particularly in order to improve the performance of the overall system. (C) 2015 Elsevier Ltd. All rights reserved.Öğe Thermodynamic, economic and environmental assessments in a cogeneration power plant(Taylor & Francis Inc, 2020) Tumen Ozdil, Naime Filiz; Tantekin, Atakan; Pekdur, ArzuExergoeconomic assessment with Specific Exergy Costing (SPECO) technique and an exergoenvironmental analysis for a cogeneration system have been implemented to show the relation among thermodynamics and economical data and environmental impact of each component on the system. Depending upon the outcomes of exergoeconomic analysis, the unitary exergy price and exergy price of the natural gas have been counted as 0.05 US$/GJ and 490.23 US$/h, respectively. The unitary exergetic price and exergetic price of the steam have been counted as 158.84 US$/GJ and 2958.17 US$/h, respectively. Furthermore, the capital investment price, operating and maintenance price, and total price of the cogeneration system have been calculated to be 2185.50, 2316.60, and 4502.08 US$ per hour, respectively. The unitary environmental impact rate and environmental impact rate of the electricity, which is produced in the turbine, have been reckoned as 0.22 mPts/GJ and 0.02 mPts/h, respectively. Moreover, the effects of various fuel loading conditions and steam pressures (from 4 bar to 12 bar) on exergy prices have been investigated. The amount of fuel loading decreases, the exergy price of fuel, steam, and electricity also decreases. As the steam pressure goes up, the price of exergy loss for the boiler goes up whilst the exergy price of steam decreases.Öğe Thermodynamic, economic and environmental assessments in a cogeneration power plant(Taylor & Francis Inc, 2020) Tumen Ozdil, Naime Filiz; Tantekin, Atakan; Pekdur, ArzuExergoeconomic assessment with Specific Exergy Costing (SPECO) technique and an exergoenvironmental analysis for a cogeneration system have been implemented to show the relation among thermodynamics and economical data and environmental impact of each component on the system. Depending upon the outcomes of exergoeconomic analysis, the unitary exergy price and exergy price of the natural gas have been counted as 0.05 US$/GJ and 490.23 US$/h, respectively. The unitary exergetic price and exergetic price of the steam have been counted as 158.84 US$/GJ and 2958.17 US$/h, respectively. Furthermore, the capital investment price, operating and maintenance price, and total price of the cogeneration system have been calculated to be 2185.50, 2316.60, and 4502.08 US$ per hour, respectively. The unitary environmental impact rate and environmental impact rate of the electricity, which is produced in the turbine, have been reckoned as 0.22 mPts/GJ and 0.02 mPts/h, respectively. Moreover, the effects of various fuel loading conditions and steam pressures (from 4 bar to 12 bar) on exergy prices have been investigated. The amount of fuel loading decreases, the exergy price of fuel, steam, and electricity also decreases. As the steam pressure goes up, the price of exergy loss for the boiler goes up whilst the exergy price of steam decreases.
