Akin Kutlar - Profile on Academia.edu (original) (raw)

Papers by Akin Kutlar

Fen Bilimleri Enstitüsü, 1999

Benzin (otto) motorunda kısmi yükte yakıt tüketimini azaltmaya yönelik bir yöntem: Fakir karışımlı kademeli dolgulu motor

Mühendis ve Makina, 2000

Thermal Science, 2018

In this study, the effects of small amount of hydrogen addition into the intake of compression ig... more In this study, the effects of small amount of hydrogen addition into the intake of compression ignition engine on the performance and emissions characteristics of single cylinder, air cooled, direct injection, compression ignition engine were experimentally investigated. An electrolysis unit was built to produce hydrogen peroxide, which was then fed into the intake manifold of the compression ignition engine. The compression ignition engine was tested with different amount of hydrogen (0.15, 0.30, 0.45, and 0.60 Lpm) at different engine load (5%, 25%, 50%, 75%, and full load) and the constant speed, 2200 rpm. Experimental results show that increasing amount of hydrogen into the inlet air resulted to decrease in brake specific fuel and energy consumption while resulted to increase brake thermal efficiency at all load conditions due to uniformity in mixture formation and higher flame speed of hydrogen. The better combustion improved exhaust emission. However, exhaust temperature only increased for 0.6 Lpm hydrogen addition into the inlet air at higher loads resulting in higher quantity of nitrogen oxides formation.

Stress analysis of a Wankel engine eccentric shaft under varied thermal conditions

Materials Testing, 2019

In this study, the eccentric shaft of a 13B MSP (Multi Side Port) single-rotor Wankel test engine... more In this study, the eccentric shaft of a 13B MSP (Multi Side Port) single-rotor Wankel test engine was examined. The eccentric shaft was studied in two parts, both through modeling and experimentally. The eccentric shaft was modeled via a workbench module using ANSYS software. Here, the shaft was modeled according to the original dimensions at different speeds ranging from 1000 to 10000 rpm under different operating temperatures (25, 50 and 90 °C). In the analysis, von Mises stress and corresponding deformations were examined under the specified conditions. Afterwards, the stress and deformation of the eccentric shaft were experimentally investigated in engine tests performed at low loads and speeds. The eccentric shaft broke after approximately 200 hours. It was found that broken region was specified to critical points for validity of the applied model used in the current study. Thus, it was shown deformation and stress values can be predicted by numerically modeling the eccentric s...

Fuel, 2020

In this study, a single-rotor multi side port Wankel research engine and a single cylinder spark ... more In this study, a single-rotor multi side port Wankel research engine and a single cylinder spark ignition (SI) engine having three different type combustion chamber geometry (MR, Cylindrical bowl, Flat) were used. Engine experiments were performed at 2000 rpm, 3 bar and 5 bar bmep (brake mean effective pressure) and stoichiometric conditions. Combustion analysis was performed for Wankel and a reciprocating SI engine with three types combustion chamber geometries, which are not included in the literature. In the Wankel engine, the maximum pressure value was lower than the reciprocating SI engines and the maximum pressure obtained far away from the TDC. The reason of this is lower burning velocity and combustion progress toward the expansion stroke. Wankel engine's lower burning velocity also reduced the maximum temperature values. The normalized cumulative heat release rate was about 15% higher than the reciprocating SI engine with different combustion chambers. In Wankel engine, NO emissions are 15-45% lower due to the lower combustion temperatures. On the contrary, THC emissions were up to two times higher due to the combustion chamber geometry and absence of squish effect. The MR type combustion chamber has the highest combustion speed and pressure value due to the intense flow and mixture conditions. In the Wankel engine, combustion process is shifted toward the expansion phase, thus resulting to the lower thermal efficiency. In order to improve this process, additional precaution, such as different mixture formation and flow intensification methods in the combustion chamber are required.

Energies, 2019

The results of experiments performed by gasoline and natural gas fuels in a single cylinder resea... more The results of experiments performed by gasoline and natural gas fuels in a single cylinder research engine were evaluated in this study. The main objective of this study is to compare exhaust gas emissions, efficiency, and burn durations for both fuels in stoichiometric and lean mixture. At the same time, cycle to cycle variation in these operating conditions should not exceed an acceptable value. In the ultra-lean mixture, gasoline fuel exceeded this determined limit before Compressed Natural Gas (CNG). Therefore, the reduction in NO was restricted by cyclic variations. In combustion analysis, although the burn duration of the gasoline in stoichiometric conditions was shorter than CNG, this situation reversed in favor of CNG in the ultra-lean mixtures. Contrary to some studies in the literature, the spark advance and ignition delay for CNG were the same or shorter than gasoline in this study. The primary reasons for this change are the high compression ratio and the different comb...

Dört zamanlı kıvılcım ateşlemeli motorlarda kısmi yükte yakıt tüketimini azaltmak için yeni bir yöntem: Çevrim atlatmalı motor

Mühendis ve Makina, 2007

Skip cycle is a working strategy for spark ignition engines, which allows changing the effective ... more Skip cycle is a working strategy for spark ignition engines, which allows changing the effective stroke of an engine through skipping some of the four stroke cycles. This study proposes a new mechanism to achieve the desired skip-cycle strategy for internal combustion engines. The air and fuel leakage, which occurs through the gas exchange, negatively affects the efficiency of the engine at high speeds and loads. An absolute sealing is assured by direct use of poppet valves, which are kept in fully closed position during the skipped mode. All the components of the mechanism were designed according to the real dimensions of the Anadolu Motor's gasoline engine and modeled in 3D by means of CAD software. As the mechanism operates in two modes, two dynamically equivalent models are established to obtain the force and strength analysis for critical components.

One of the most difficult problems to be resolved during the development of diesel engines is to ... more One of the most difficult problems to be resolved during the development of diesel engines is to decrease nitrogen oxides, soot (smoke) and particulates in exhaust emissions, without decreasing performance and efficiency, to limits proposed by emission standards, which will be in force in near future. During last years by cooperation and projects with different engine manufacturers Istanbul Technical University developed new fuel-air formation and combustion mechanism that is used in actual combustion chambers of diesel combustion engines. In this paper are presented some theoretical and test results of diesel engines developed by applying this new mechanism.

Modernization of the Tumosan Tractor Diesel Engines by Using New Combustion Chamber

One of the most difficult problems to be resolved in development of diesel engines is to decrease... more One of the most difficult problems to be resolved in development of diesel engines is to decrease nitrogen oxides, soot (smoke) and particulates in exhaust emissions, without decreasing performance and efficiency, to limits proposed by emission standards which have being more and more stricter. As in developed European countries, by taking in force the 2004/26/EC standard in Turkey the dense research and development activities and practical usage of their positive results is occurred as a problem to be solved in future 2-3 years in developments of offroad vehicle’s engines. During last years by cooperation and projects with one of the biggest internal combustion engine manufacturers TUMOSAN and other factories Istanbul Technical University developed new combustion mechanisms that are used in actual CCs. In this paper are presented some theoretical and test results obtained during the development of TUMOSAN’s diesel engines.

The main process which is directly related with the improvement of performance, fuel economy and ... more The main process which is directly related with the improvement of performance, fuel economy and emission characteristics of an internal combustion engine is the combustion process itself. In order to find an optimum combustion process that meets these demands a simple Vibe based theoretical computation model was first established. Using this theoretical model some results are obtained and presented in this study. A construction of a suitable combustion chamber that will realize this process is designed and tested in a single cylinder experimental diesel engine. Experiment results of this novel combustion chamber are presented and compared with those results obtained from engine equipped with the standard combustion chamber. Indicated cylinder pressure and related pressure rise and heat release curves of the novel combustion chamber are compared with those of standard engine combustion chamber. The comparison of both type diesel engines is done at the same original maximum power. Th...

Effect of Leading and Trailing Spark Plugs on Combustion, Fuel Consumption and Exhaust Emission in a Wankel Engine

Arabian Journal for Science and Engineering, 2021

The aim of this study was to determine the ignition advance difference between the leading and tr... more The aim of this study was to determine the ignition advance difference between the leading and trailing spark plugs found in the 13B-MSP (Multi Side Port) Wankel engine. The optimum ignition advance difference between the two-spark plugs had been determined by examining brake specific fuel consumption, emissions, p–V diagram, cumulative heat release rate and cyclical variations on the engine. Better results were obtained, if the advance difference was 15 or 20° in terms of total hydrocarbon and brake specific fuel consumption. It was observed that as the ignition advance difference decreased between the two-spark plugs, the combustion started earlier and completed in a short time, and when the ignition advance difference increased, the combustion started later and slower. Therefore, combustion improved with the ignition advance difference being 15°. The average of maximum pressures for 200 cycles was found as 20.48 bar, 26.11 bar and 17.36 bar in 5°, 15° and 30° ignition advance differences, respectively. 15° ignition advance difference was found to be faster to burn than other advance differences. It was observed that the optimum advance difference between the leading and trailing spark plugs should be 15°. Subsequently, single-spark plug (Trailing plug) and two-spark plug (Trailing + Leading plug) experiments were performed on different loads. As a result, two-spark plug compared to single-spark plug, fuel consumption and emissions decreased, and it was observed that combustion became better by increasing in-cylinder pressure and heat release rate.

Konya Journal of Engineering Sciences, 2020

In this study, the optimum advances for parameters such as specific fuel consumption, emissions w... more In this study, the optimum advances for parameters such as specific fuel consumption, emissions were investigated in ignition advances below 10 0 EA and above 10 0 EA. Cylinder pressure was measured for calculating the heat release rate. 13B MSP (Multi Side Port) single rotor and port fuel injection Wankel engine was used in the experiments. In this context, single rotor Wankel test engine was operated at 2000, 3000 and 4000 rpm engine speed, part loads and λ = 1 condition. The optimum ignition advance is based on the value at which the maximum torque is obtained. Thus, the effect of ignition advance was investigated on Wankel engine. As a result, it is observed that ignition advance has a significant effect on emissions, in-cylinder pressure and fuel consumption in Wankel engine.

Gazi Üniversitesi Mühendislik-Mimarlık Fakültesi Dergisi, 2020

The use of biodiesel and diesel blends in cycle test  Fuel properties of the blends of Canola Bi... more The use of biodiesel and diesel blends in cycle test  Fuel properties of the blends of Canola Biodiesel and Diesel  Legal exhaust emissions of the blends of Biodiesel and Diesel Figure A. Chassis dynamometer measurement system Purpose: Alternative fuels are convenient substitutes to conventional fuels in the automotive industry which reduces emission based air pollution and dependency on use of conventional fuels. Owing to the stringent emission regulations introduced by the European Union (EU), the use of biodiesels, an alternative fuel, has become quite popular over the last decade. In this study, a two-phase experimental analyses were carried out to investigate the effects of biodiesel produced from canola oil (BD-CO) on emission and performance of diesel engines. In the first part, EURO-5 compliant diesel passenger car was tested under NEDC to investigate the effects of biodiesel on vehicle emissions and performance. In the second part, in order to examine the effect of biodiesel on combustion parameters, it was tested in engine partial and full load working conditions. Theory and Methods: The NEDC testing was conducted with diesel and four different biodiesel blends of diesel to investigate emissions of each phases of the NEDC. Experiments started with the NEDC testing. First, to drain fuel tank, vehicle was driven in the chassis dynamometer until the all fuel was depleted. Afterwards, vehicle was refueled with three liters of prepared test fuel. Cycle test was performed according to the UNECE R83. To eliminate the uncertainties resulting from ambient conditions and measurement devices, three sets of NEDC tests were performed for each fuel. Besides, in the second part steady state experiments were conducted at partial and full load working conditions of the engine. To achieve the same test conditions before taking the measurements, the engine was run for 15 minutes at 50 km/h in the 2 nd gear of the vehicle to achieve engine coolant and exhaust temperature of 90°C and 200°C respectively. The emissions, power and in-cylinder pressure values were measured during the experiments. Results: Mixing the 10% biodiesel to the diesel has reduced the ignition delay by 2 crank angles and combustion has started 2 crank angles earlier compared to pure diesel. The 10% biodiesel additive improved HC, CO and soot emissions by 15%, but caused a 2% increase in fuel consumption due to its low calorific value. In addition, NOx emissions increased by 4% with the blended biodiesel. Conclusion: The use of biodiesel should be encouraged to reduce toxic emissions and dependency to fossil fuels. CO, HC and PN emissions can be reduced with the use of biodiesel and exhaust aftertreatment equipment can be smaller and less expensive compared to usage of pure diesel.

In this paper, the effects of biodiesel on performance and emission of the current and new-coming... more In this paper, the effects of biodiesel on performance and emission of the current and new-coming regulation cycles, namely the New European Driving Cycle (NEDC) and the Worldwide Harmonized Light Vehicles Test Cycle (WLTC), were investigated by conducting tests on a passenger car, Euro-5 Ford Fiesta, equipped with a 1.5-liter diesel engine. In a two-axle chassis dynamometer test bed, NEDC and WLTC were performed with pure diesel and biodiesel-to-diesel blend (30% biodiesel, 70% diesel in volume). A substantial reduction in CO, HC, and PN emissions was observed for both the NEDC and WLTC when biodiesel was used. Besides, it was found that the WLTC has higher load and velocity profile compared to the NEDC. Moreover, lower CO, HC, and PN emissions were observed with B30 fuel under WLTC compared to the NEDC. Nevertheless, slightly higher CO2 and substantially higher NOx emissions were observed for the WLTC compared to the NEDC.

SAÜ Fen Bilimleri Enstitüsü Dergisi, 2017

The effects of different compression ratios and spark advances on the performance and emissions o... more The effects of different compression ratios and spark advances on the performance and emissions of a spark ignition engine with a new combustion chamber ABSTRACT Nowadays, there are different ideas about the future of internal combustion engines. Despite the thoughts about internal combustion engines that are old technology, there have been many new researches about internal combustion engines. Reduction of fuel consumption and improving of the exhaust emissions are the main research topics in the spark ignition engines in the present day. The aim of this paper is to examine experimentally the effect of different compression ratios and excess air coefficients with a new designed chamber geometry on the performance and exhaust emissions of a single cylinder, which is water-cooled, port fuel injection and spark ignition engine. A new combustion chamber geometry was designed and three same combustion chamber geometries with different compression ratios were manufactured. It is expected from the combustion chamber shapes to run the engine properly in the lean mixtures. So, the decrease of fuel consumption and the decrease of NO emission are predicted. The experiments were tested at seven different excess air coefficients (1,0; 1.10; 1.20; 1.30; 1.45; 1.60 and 1.70), three different compression ratios (10.5; 12 and 14), different spark advances, wide open throttle (WOT) and the constant speed, 2500 rpm. The amount of fuel, spark advance and throttle condition were electronically controlled using an engine control unit (ECU) which is designed in the our laboratory by us. While the engine was running with lean mixtures, NO emissions decreased. When NO emissions are reduced, it will decrease the need for NO catalyst. Experimental results show that increasing of compression ratio and decreasing of spark advance leaded to decreasing of NO emissions substantially at nearly mean effective pressure values. In addition, the cycle-to-cycle variations are reduced at the lean mixtures (EAC>1.45) with the suitable combustion chamber geometry on the spark ignition engines and the engine remained stable.

Hydrogen Use in Vehicles

World Renewable Energy Congress VI, 2000

Publisher Summary This chapter discusses the methods of hydrogen production, distribution, and st... more Publisher Summary This chapter discusses the methods of hydrogen production, distribution, and storage of hydrogen in comparison to other energy sources and advances in these fields. Expectations from hydrogen as an alternative automotive fuel in the future are examined. The use of renewable energy sources for vehicles became more attractive as new technologies increase energy efficiency and decrease costs. Alternative electric power technologies include hydroelectric, wind driven turbines, solar power, and geothermal sources. Alternative renewable fuels include ethanol, methanol, methane, hydrogen, and others. Meanwhile, fossil fuels are a limited resource, and their combustion products pollute the environment with a variety of harmful compounds. The use of hydrogen as a fuel in internal combustion engine presents some more engineering challenges, but recent efforts have shown that none of the problems are insurmountable and the benefits outweigh the limitations.

Le programme est établi chaque fois pour cinq ans et il est conçu comme un plan mobile, c'est-2, ... more Le programme est établi chaque fois pour cinq ans et il est conçu comme un plan mobile, c'est-2, place de Metz-Luxembourg Compte courant postal: Luxembourg n° 191-90

Prediction of oil dilution formation rate due to post injections in diesel engines by using Gaussian process

Fuel