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Gazi University · Faculty of Technology

Energy need is one of the indispensable needs of human beings. At this point, the important thing is to use the available resource that is sustainable, economical, and sensitive to the ecosystem. For this reason, alternative fuels will maintain their importance in the future as they do today. Internal combustion engines continue to be used as power...

Stirling engines are external combustion engines. This feature eliminates the possible dependency of the engine on a specific energy resource and allows it to work with diverse energy sources, especially solar and other renewable energy sources. Also, Stirling engines could be built in different configurations that have a significant impact on the...

External combustion Stirling engines are considered as an alternative to the solution of increasing energy and environmental problems due to their ability to work with any heat source and to be an efficient energy conversion system. In this study, the effects of hot-end and cold-end connections of power and displacer cylinders on the performance of...

In this study, a structurally simple alpha-type Stirling engine was proposed, and its combined thermodynamic-dynamic analysis was conducted. A simulation program capable of working as nodal analysis, isothermal nodal analysis, and combined dynamic-thermodynamic nodal analysis was developed. Some performance characteristics of the crank-shifted engi...

Geleneksel gama tipi Stirling motorlarında iki silindir mevcut olup silindirlerden birisi aracılığı ile çalışma gazının sıkıştırılması ve genişletilmesi işlemleri, diğeri aracılığı ile çalışma gazının sabit hacimde ısıtılması ve soğutulması işlemleri gerçekleştirilmektedir. Geleneksel gama tipi motorlarda soğuk ve sıcak hacimlerin aynı silindirde b...

Biomass fuels are important alternatives to conventional energy sources such as petroleum-based fuels. Biomass fuels especially alcohols have been used in passenger cars. Alcohol blends with gasoline constitute a general use. Particularly, modification of the engine is not required when using at low rates, like gasohol. Gasohol consists of a mixtur...

İçten yanmalı motorlarda gücün elde edilmesi yanma olayının bir sonucunun olması ve yanmanın belirli bir süre içerisinde gerçekleşmesi kirletici emisyonlarını kaçınılmaz yapmaktadır. Ancak emisyon kontrol yöntemleriyle bu durum kontrol altına alınmaya çalışılmaktadır. Bu çalışmada da tek nokta yakıt enjeksiyonuna sahip buji ile ateşlemeli motorda i...

Oxygenated compounds (alcohols and ethers) have attracted attention as additives to gasoline to improve fuel specifications. These have a high octane number and contain oxygen. So, they decrease the knocking tendency and lead to the lowering of some exhaust emissions such as carbon monoxide (CO). In this study, methyl tertiary butyl ether (MTBE), a...

EGR is one of the most significant strategies for reducing especially nitrogen oxides (NOx) emissions from internal combustion engines. The thermal efficiency of spark ignition engines is lower than compression ignition engines. Because there is a knocking tendency when the compression ratio is increased in spark ignition engines. EGR can be used i...

Today, petroleum-based fuels are widely used in internal combustion engines. The researchers,are studying to improve the properties of existing fuels as well as the fuels can be alternatives to petroleum-based fuels. The use of fuel additives intended to improve engine performance and exhaust emissions. In this study, effects of the powermax additi...

Today, petroleum-based fuels are widely used in internal combustion engines. The researchers,are studying to improve the properties of existing fuels as well as the fuels can be alternatives to petroleum-based fuels. The use of fuel additives intended to improve engine performance and exhaust emissions. In this study, effects of the powermax additi...

Alcohols have been used as a fuel for engines since 19th century. Among the various alcohols, ethanol is known as the most suited renewable, bio-based and ecofriendly fuel for spark-ignition (SI) engines. The most attractive properties of ethanol as an SI engine fuel are that it can be produced from renewable energy sources such as sugar, cane, cas...

In this study, a single cylinder β-type Stirling engine with the swept volume of 192 cc was manufactured and performance tests were conducted. Experiments were performed at 800, 900 and 1000°C heater temperatures and 1, 1.5, 2, 2.5 and 3 bar charge pressures. Air was used as the working fluid. Torque and power variations were obtained for different...

This study consists of two cases: (i) The experimental analysis: Ethanol obtained from biomass can be used as a fuel in spark ignition engines. As renewable energy source ethanol, due to the high octane number, low emissions and high engine performance is preferred alternative fuel. First stage of this study, ethanol–unleaded gasoline blends (E10,...

In this study, the effects of using unleaded gasoline (E0) and unleaded gasoline–ethanol blends (E10, E20 E40 and E60) on engine performance and exhaust emissions have been experimentally investigated. The investigation was conducted on a Hydra single-cylinder, four-stroke, spark ignition engine. The experiments were performed by varying the compre...

Renewable energy sources for the gasoline engines alcohols gain importance recently. These renewable energy sources have attracted the attention of researchers as alternative fuel due to their high octane number. In addition, these are also clean energy sources and can be obtained from the biomass alcohols with low carbon like ethanol. In this stud...

In this study, the effects of using unleaded gasoline (E0) and unleaded gasoline–ethanol blends (E10, E20 E40 and E60) on engine performance and exhaust emissions have been experimentally investigated. The investigation was conducted on a Hydra single-cylinder, four-stroke, spark ignition engine. The experiments were performed by varying the compre...

In this study, a beta-type Stirling engine, with a 192 cc total swept-volume, was manufactured and its performance tested at atmospheric pressure. The hot-source temperature is chosen as a fundamental parameter of the experimental study. Experiments were performed with an electrical heater at 800, 900 and 1000 °C temperatures. Torque and output-pow...

Adding any inert gas as diluent to the inlet air reduces oxides of nitrogen (NOx) emissions. In this study, carbon dioxide (CO2) was used as diluent and introduced to the intake manifold of a diesel engine at a ratio of 2%, 4% and 6% respectively. The investigation was conducted on a four stroke, four-cylinder, indirect injection (IDI), turbocharge...