Energy Systems Engineering / Enerji Sistemleri Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/4752
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Article Citation - WoS: 9Citation - Scopus: 11Experimental Investigation of Spray Characteristics of Ethyl Esters in a Constant Volume Chamber(Springer, 2024) Ulu, A.; Yildiz, G.; Özkol, Ü.; Rodriguez, A.D.Abstract: Biodiesels are mainly produced via the utilization of methanol in transesterification, which is the widespread biodiesel production process. The majority of this methanol is currently obtained from fossil resources, i.e. coal and natural gas. However, in contrast with methanol, biomass-based ethanol can also be used to produce biodiesels; this could allow the production line to become fully renewable. This study aimed to investigate the spray characteristics of various ethyl ester type biodiesels derived from sunflower and corn oils in comparison to methyl esters based on the same feedstocks and reference petroleum-based diesel. Spray penetration length (SPL) and spray cone angle (SCA) were experimentally evaluated in a constant volume chamber allowing optical access, under chamber pressures of 0, 5, 10 and 15 bar and injection pressures of 600 and 800 bar. Sauter mean diameter (SMD) values were estimated by using an analytical correlation. Consequently, ethyl esters performed longer SPL (2.8–20%) and narrower SCA (5.1–19%) than diesel under ambient pressures of 5 and 10 bar. Although the SMD values of ethyl esters were 48% higher than diesel on average, their macroscopic spray characteristics were very similar to those of diesel under 15 bar chamber pressure. Moreover, ethyl esters were found to be very similar to methyl esters in terms of spray characteristics. The differences in SPL, SCA and SMD values for both types of biodiesels were lower than 4%. When considering the uncertainty (± 0.84%) and repeatability (±5%) ratios, the difference between the spray characteristics of methyl and ethyl esters was not major. Graphical abstract: [Figure not available: see fulltext.] © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.Book Part Citation - Scopus: 4Investigation of a New Methanol, Hydrogen, and Electricity Production System Based on Carbon Capture and Utilization(Springer, 2023) Khani, Leyla; Mohammadpourfard, MousaIt 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: 1A New Stable Solar System for Electricity, Cooling, Heating, and Potable Water Production in Sunny Coastal Areas(Springer, 2023) Khani, Leyla; Mohammadpourfard, MousaNowadays, 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.