Makine ve Metal Teknolojileri Bölümü

Permanent URI for this communityhttps://hdl.handle.net/20.500.12514/115

Browse

Now showing 1 - 5 of 5

Energy and exergy analysis of an industrial corn dryer operated by two different fuels
(International Journal of Exergy, 2021) Ünal, Fatih
In this study, the data obtained after converting an industrial horizontal type corn dryer that meets its drying air temperature from coal to natural gas was compared by thermodynamic analyses. Before starting the drying process, it was assumed that the corn type DKC6050 with 24-25% corn inlet humidity dries when it reaches approximately 14% corn outlet humidity, which is the storage condition after the drying process. Energy and exergy efficiencies, drying rates, unit drying costs, specific moisture extraction rate, and specific energy consumption values of the analysed systems were determined using the data obtained from the experiments carried out at 90, 100 and 110 C drying temperatures. On the other hand, it was also determined that the unit drying cost was approximately 0.1-0.45 €/kg and the specific energy consumption was less than approximately 1,000-8,000 kJ/kgwater. Also, emission values released to the environment were calculated for both systems based on the amount of energy required for drying.
Energy, exergy and exergoeconomic analysis of solar-assisted vertical ground source heat pump system for heating season
(KOREAN SOC MECHANICAL ENGINEERS, 2018) Unal, Fatih; Temir, Galip; Koten, Hasan
The purpose of this study is to evaluate the experimental performance of a solar assisted vertical ground source heat pump system (VGSHP) for the winter climatic conditions of Mardin, which is in the South-Eastern Anatolia region of Turkey. For this aim, an experimental analysis was performed on solar assisted VGSHP system, which was designed to meet the heating needs of an experimental room, during the heating season (10.01.2013/03.31.2014). The experimentally obtained results were used to calculate energy, exergy and exergoeconomic analyses of the system and its components. The energy efficiency, exergy efficiency and exergoeconomic factors of the entire system were 67.36 %, 27.40 % and 60.51 %, respectively. In this study, the system was proposed for disseminating the use of alternative technologies supported by renewable energy systems and it has been tested for the first time in Mardin to meet its heating needs with convectional systems. The experimental results showed that the proposed solar assisted VGSHP system can be used for residential heating in Mardin and similar regions. As a result, it has been detected that the system is very effective in both reducing energy consumption and decreasing emissions of green-house gases.
Perspective of safflower (Carthamus tinctorius) as a potential biodiesel feedstock in Turkey: characterization, engine performance and emissions analyses of butanol–biodiesel–diesel blends
(Taylor and Francis Ltd., 2017) Al-Samaraae R.R.; Atabani A.E.; Uguz G.; Kumar G.; Arpa O.; Ayanoglu A.; Mohammed M.N.; Farouk H.
Safflower (Carthamus tinctorius) is widely farmed in Turkey. This study investigates the physicochemical properties of safflower biodiesel and its blends with Euro diesel and butanol. A polynomial curve-fitting method was used to predict kinematic viscosity and density of the ternary blends. Furthermore, characteristics such as DSC, FT-IR, UV-Vis and TGA were adopted to evaluate the influence of butanol addition on biodiesel–diesel blends. Engine performance parameters such as BP, torque and BSFC and emissions such as CO, HC, NOx and EGT were studied. Safflower methyl ester satisfied both EN 14214 and ASTM D 6751 standards regarding viscosity, flash point and density. However, iodine value was quite high. Oxidation stability fails to satisfy either standard. This is due to the high level of unsaturated fatty acids (91.05%). A reduction in BP, torque, HC and CO coupled with an increase in BSFC, NOx emissions and EGT was observed for all blends compared to Euro diesel. Overall, all blends appear to be good alternatives to biodiesel–diesel blends. This work supports that biodiesel can be blended with diesel and butanol as ternary blends (up to 20%) for use as a fuel in compression ignition (CI) engines. Therefore, combustion characteristics of blends shall be further investigated. © 2017 Informa UK Limited, trading as Taylor & Francis Group
Tear-off Wear Mechanism of Sintered Diamond Tool in Cutting SiC Particle-strengthened Epoxy Composite
(Elsevier Science Pub., 1997) Afaghani, Jamal Eldeen; Yamaguchi, Katsumi; Nakamoto, T.
This study concerns the wear of sintered diamond tools in the cutting of SiC-particle–epoxy composites. The effects of the SiC particle size, volume ratio in the composite and diamond grain size of the cutting tool on tool wear were investigated. The experimental work has shown that a coarse-grained diamond tool exhibits higher wear resistance than a corresponding fine-grained tool. Greater tool wear was obtained in cutting the composites that had coarser particles and a higher volume ratio of SiC. Moreover, it was found that the tool wear increases drastically when the SiC particles are larger than the tool grains. A wear model of the tool was proposed, in which the tool is worn mainly by the ‘tear-off’ mechanism of the diamond grains. This model could explain the experimental results by comparing the pushing force of an SiC particle with the tear-off resistance of the diamond grains of the tool. Finally, a fatigue-like empirical curve was established. This curve can be used to predict the wear of the tool during cutting of the composite. q 1997 Elsevier Science S.
Whisker Behavior and Tool Wear in Cutting of Unidirectional SiC Whisker Reinforced Plastics
(Elsevier Science Pub., 1996) Jamal ElDeen AFAGHANI; K. Yamaguchi
This study concerns the cutting process of unidirectional Sic whisker-reinforced plastic composite. The effects of the grain size of the polycrystalline diamond tool and the Sic whisker orientation on the tool wear were investigated. The tool with fine grain size exhibited higher wear rates. The greatest tool wear was with the composite having longitudinal alignment of whiskers. The cutting processes of various orientations of whiskers were observed by scanning electron microscopy at low speed using a specially designed device. Moreover, models were proposed for cutting the Sic whisker-plastic composite and for wear of sintered diamond tools.

Browse

Browsing Makine ve Metal Teknolojileri Bölümü by Access Right "info:eu-repo/semantics/closedAccess"