Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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Now showing 1 - 10 of 14
  • Conference Object
    Citation - Scopus: 2
    Co2 Capture by Pei-Impregnated Alumina Sorbents
    (ISRES Publishing, 2023) Turgut, Furkan; Kostik, Simge; Erdoğan, Barış; Çağlar, Başar
    Direct air capture (DAC) or direct CO2 extraction from ambient air is a promising approach to reduce greenhouse gas emissions caused by both distributed (location independent) and point sources (location specific). Solid sorbents have been considered as more effective for DAC compared to the liquid counterpart since they have a faster kinetic and avoid volatile and heat losses due to the absence of evaporation of liquids. In this study, the alumina-supported polyethyleneimine (PEI) material was chosen as solid sorbents and their CO2 capture performance for different PEI loadings (20, 35, 50 wt%), flow rate (15, 30, 45 L/h) and adsorption temperatures (30, 40, 50, 60 °C) was investigated. Sorbents were prepared by using wetness impregnation method and their physical and chemical properties were characterized by several techniques such as N2 adsorption-desorption (surface area, pore size and volume), Scanning Electron Microscopy-SEM (surface morphology, surface chemical composition). The CO2 capture performance of sorbents were analyzed under different CO2 concentrations and the cyclic (adsorption-desorption) behavior of the sorbents were tested. The results show that alumina-supported PEI adsorbents are promising materials for CO2 capture with high CO2 adsorption capacity and stability. © 2023 Published by ISRES.
  • Book Part
    Citation - Scopus: 4
    Investigation of a New Methanol, Hydrogen, and Electricity Production System Based on Carbon Capture and Utilization
    (Springer, 2023) Khani, Leyla; Mohammadpourfard, Mousa
    It is well-known that clean energy transition requires low carbon emission. The increase in population, economic development, and human welfare demands has led to a rise in energy consumption, mainly supplied by fossil fuels. However, burning fossil fuels produces carbon dioxide, which is a greenhouse gas and a contributor to environmental problems. Therefore, carbon capture and conversion to different products have gained attention. On the other hand, combining two or more different thermodynamic systems for simultaneous production of various demands from one energy source looks reasonable. In this regard, a new trigeneration system is proposed to decrease atmospheric carbon dioxide emission and produce methanol, hydrogen, and power. A flue gas stream with a defined composition, solar energy, and atmospheric air are the system’s inlets. Then, mass, energy, and exergy balance equations are applied for each subsystem to investigate the system’s thermodynamic performance. Also, the effect of changing operating parameters on the performance of each subsystem is studied. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.
  • Book Part
    Citation - Scopus: 1
    A New Stable Solar System for Electricity, Cooling, Heating, and Potable Water Production in Sunny Coastal Areas
    (Springer, 2023) Khani, Leyla; Mohammadpourfard, Mousa
    Nowadays, more attention is paid to provide clean energy products with low environmental pollution in a decentralized way. Many coastal rural areas suffer from freshwater and electricity scarcity, especially in hot weather condition. Meanwhile, these regions have a great access to intense solar radiation and seawater. Hence, it seems logical to use the available solar energy in those places to provide to necessities like power, heating, and cooling. A new solar cooling, power, heating, and freshwater production system is designed, evaluated, and optimized in this research. The proposed system is composed of several subsystems to generate each product with high efficiency and reliability. Solar energy is unavailable at night, so molten salt energy storage is used to establish the steady operation of the system. Then, the system is evaluated from thermodynamic and exergoeconomic viewpoints, and a parametric study is accomplished to study the effect on the system performance of key variables. In the end, the system is optimized to determine its best operating condition for different cases. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.
  • Article
    Citation - Scopus: 21
    The Developing Flow Characteristics of Water - Ethylene Glycol Mixture Based Fe3o4 Nanofluids in Eccentric Annular Ducts in Low Temperature Applications
    (Elsevier, 2022) Çobanoğlu, Nur; Banisharif, Alireza; Estelle, Patrice; Karadeniz, Ziya Haktan
    Natural circulation loops with double pipe heat exchangers at heating and cooling ends have a potential to be used in the refrigeration systems as an alternative to suction line heat exchangers. The heat transfer capability of such natural circulation loops depends on the geometrical parameters as well as thermophysical properties of the working fluid. This study aims to investigate the effect of water-ethylene glycol mixture based Fe3O4 nanofluids (0.01, 0.05 and 0.1 vol.%) on the annular flow propagation and heat transfer in the annuli of double pipe heat exchanger at low pressure side of the refrigeration cycle. In addition to increased non-dimensional velocity values due to the lower viscosity and higher non-dimensional temperature values with expanded temperature gradient, improved heat transfer by nanofluids shows that they can be used as secondary heat transfer fluids at low-pressure side in refrigeration systems. Although the maximum transferred (13.6% improvement compared to base fluid) heat observed for the highest concentration, the nanofluids with smallest concentration has the minimum pressure drop value (25% reduction compared to base fluid) and the highest performance evaluation criteria (PEC) value (PEC = 1.08) with tiny increase in exergy destruction (1.45% compared to base fluid)
  • Conference Object
    Citation - Scopus: 11
    Wind-Solar Site Selection Using a Gis-Mcdm Approach With an Application in Kayseri Province/Turkey
    (Institute of Electrical and Electronics Engineers Inc., 2021) Genç, Mustafa Serdar; Karipoğlu, Fatih
    Renewable and sustainable energy sources such as wind, biomass, geothermal and solar are defined as a less harmfully to environment than other fossil fuels reserves. At the last decade, the demand of energy because of the rising of industrialization and population is increasing in Turkey. Thus, investments on renewable energy sources especially wind and solar energy systems are increasing rapidly because of unlicensed energy production legislation published by Turkish Ministry of Energy and Natural Sources. Although Turkey has high solar and wind capacity, there has not been develop a tool to determine the suitable regions for hybrid energy systems. In this study, geographical information systems (GIS) and Multi-criteria-base method (MCDM) are used to determine the suitable regions for wind-solar hybrid energy systems of Kayseri Province under potential and environmental impacts. The results shows (2.080 km2) %12.3 of Kayseri is suitable for hybrid energy system investment. © 2021 IEEE.
  • Conference Object
    Investigation of Optimum Parameters for Biodiesel Production Technique Using Thf (tetrahydrofuran) as Solvent Agent
    (Czech Society of Chemical Engineering, 2006) Çağlar, Emre
    Biodiesel (fatty acid methyl ester), which is derived from triglycerides by transesterification with alcohol, has attaracted considerable attention during the past decades as a renewable, biodegradable, non toxic fuel. Several processes for biodiesel fuel production have been developed, among which the transesterification using alkali catalysis gives high yields of conversion. The main problem of transesterfication reaction is that the reactants are not readily miscible. This leads to a longer reaction time and so higher fixed capital investments and product costs. Introducing a solvent agent such as THF (tetrahydrofuran), enables the reaction to be one phase. Therefore, complete conversion is achieved up to 99.89 wt% in very short reaction time such as 10 minutes. In this report, the results of the experiments, carried out in the Quality Control Laboratory of Fox Petroli SPA Vasto Plant, Italy, are published. The experiments are performed to see optimum conditions of this solvent using technique. The results would lead lower capital investments and operating expenses for biodiesel production.
  • Conference Object
    Citation - WoS: 1
    Citation - Scopus: 3
    Green Smart Cities: Living Healthily With Every Breath
    (Institute of Electrical and Electronics Engineers Inc., 2019) Turhan, Cihan; Atalay, Ali Serdar; Gökçen Akkurt, Gülden
    Fifty-four percent of the world's population lives in big cities and it is projected to increase to nearly 70% by 2050s. Rapid and dense urbanization leads to smart cities which improve the quality of lives of the citizens. Therefore, development of smart cities is becoming vital. The quality of the citizens is affected by many factors including poor air quality, increased pollutants and microclimates called urban heat islands. The URBAN GreenUP project, initiated in June 2017, is a project funded under the European Union's Horizon 2020 programme. The main objective of the project is the development, application and replication of re-naturing Urban Plans in a number of European cities. In this study, measurement of nature-based solutions for mitigation of urban heat island effect and improvement of air quality for Urban GreenUP project in Izmir, will be introduced.
  • Book Part
    Citation - Scopus: 2
    Ventilation Strategies for the Preventive Conservation of Manuscripts in the Necip Paşa Library, Izmir, Turkey
    (Elsevier, 2018) Coşkun, Turgay; Şahin, Cem Doğan; Gülhan, Özcan; Durmuş Arsan, Zeynep; Gökçen Akkurt, Gülden
    Libraries are specific spaces in which the indoor microclimate should meet rigorous requirements such as the thermal comfort of humans and the conservation of books, manuscripts, and cultural property. An inadequate indoor microclimate (mainly temperature, relative humidity, and their fluctuations) in libraries may cause chemical, biological, and mechanical degradations in paper-based collections. In this chapter, the indoor microclimate of the Necip Paşa Library, the historic library located in Tire-Izmir, Turkey, is discussed from the perspective of the preventive conservation of manuscripts. The library, which has no active heating, cooling, and ventilation system, was modeled with the help of a building energy simulation tool, DesignBuilder. The indoor temperature and relative humidity were monitored throughout 1 year and the model was calibrated with respect to these measurements. To reduce the risks of the manuscripts degrading, ventilation strategies were proposed including natural and mechanical control. The results showed that risks of chemical degradation can be diminished to some extent. © 2018 Elsevier Inc. All rights reserved.
  • Conference Object
    Molecular Dynamics Study of the Thermal Conductivity of Graphene Coated Copper
    (Avestia Publishing, 2019) Toprak, Kasım; Ersavaş, Gizem
    In this study, the thermal conductivity of various size of pure copper, pure graphene and, different number of layer graphene coated copper models are studied using non-equilibrium molecular dynamics (NEMD) simulations. Our findings show that the thermal conductivity of graphene coated copper is higher than the uncoated ones. Furthermore, results also indicate that single layer graphene (SLG) model has the highest thermal conductivity as compared to the other model. Even though multiple layer graphene (MLG) has lower thermal conductivity value compare to SLG, this study shows that the thermal conductivity of MLG coated copper has higher thermal conductivity than SLG coated one. The most important finding in this study suggests that the thermal conductivity of copper can be improved using high thermal conductivity materials like graphene. © 2019, Avestia Publishing.
  • Conference Object
    Citation - Scopus: 1
    Offshore Wind Energy Estimation in the Bay of Bengal With Satellite Wind Measurement
    (IEEE, 2019) Nadi, Navilla Rahman; Badger, Merete; Bingöl, Ferhat
    The objective of this paper is to obtain appropriate offshore location in the Bay of Bengal, Bangladesh for further development of wind energy. Through analyzing the previous published works, no offshore wind energy estimation has been found related to the Bay of Bengal. Therefore, this study can be claimed as the first footstep towards offshore wind energy analysis for this region. Generally, it is difficult to find offshore wind data relative to the wind turbine hub heights, thus a starting point is necessary to identify the possible wind power density of the region. In such scenario, Synthetic Aperture radars (SAR) have proven useful in previous studies. In this study, SAR based dataset- ENVISAT ASAR has been used for Wind Atlas generation of the Bay of Bengal. Furthermore, a comparative study has been performed with Global Wind Atlas (GWA) to determine a potential offshore wind farm production in a reasonable location at the bay. The annual energy production of that offshore windfarm has been analyzed by combining SAR, GWA and ASCAT datasets. Through ASAR based Wind Atlas and GWA comparison, some differences have been found where there are less samples from the ASAR datasets. Thus, Weibull statistical analysis are performed to have a better Weibull fitting and accurate estimation of Annual Energy production (AEP). The study summarizes that, satellite datasets can be a very useful method to detect potential zone if compared with any long time statistical result and bathymetry data together. © 2019 IEEE.