Showing papers on "Four-stroke engine published in 2020"

Energy, exergy and emission analysis on a DI single cylinder diesel engine using pyrolytic waste plastic oil diesel blend

Abstract: Depletion of fossil fuels and stringent emission norms focus attention to discover an evitable source of alternative fuel in order to attribute a significant compensation on conventional fuels. Besides, waste management policies encourage the valorization of different wastes for the production of alternative fuels in order to reduce the challenges of waste management. In this context, pyrolysis has become an emerging trend to convert different wastes into alternate fuel and suitable to be used as a substitute fuel for CI engines. The current investigation provides a sustainable and feasible solution for waste plastic management by widening the gap between global plastic production and plastic waste generation. It investigates the performance and emission of a single cylinder DI four stroke diesel engine using waste plastic oil (WPO) derived from pyrolysis of waste plastics using Zeolite-A as catalyst. Engine load tests have been conducted taking waste plastic oil and subsequently a blend of waste plastic oil by 10%, 20%, and 30% in volume proportions with diesel as fuel. The performance of the test engine in terms of brake thermal efficiency is found marginally higher and brake specific fuel consumption comparatively lowest for 20% WPO-diesel blend than pure diesel. The NOx and HC emission is found lower under low load condition and became higher by increasing the load as compared to diesel. Fuel exergy was significantly increasing after blending of WPO with pure diesel, but exergetic efficiency of the blended fuels followed the reverse trend. However, increase in load of the engine improved the exergetic efficiency. The 20% WPO–diesel blended fuel is found suitable to be used as an alternative fuel for diesel engine.

A study on a solution to reduce emissions by using hydrogen as an alternative fuel for a diesel engine integrated exhaust gas recirculation

Abstract: Although diesel engines are the most reliable energy source in the transport industry, increasingly strict emissions targets and the rapid depletion of oil resources have spurred researchers to try. Research to use alternative fuels for diesel. Hydrogen is one of the best alternatives to traditional fuel. Hydrogen has its own benefits and limitations in its use as an alternative fuel in diesel engines. On the other hand, one of the effective methods to improve combustion efficiency on existing engines without changing a lot of engine structure is to add a small amount of hydrogen gas or hydrogen rich gas to the engine. Hydrogen has fast diffusion, flammable and fast burning characteristics, so when it is ignited in a mixture with traditional fossil fuels in engine cylinder, it will increase the burning speed of the fuel mixture and helps fuel burn completely, thereby increasing combustion efficiency and reducing engine emissions. A study on supplying hydrogen or hydrogen-rich gas to diesel engines right on the engine intake through the EGR flue gas recirculation system to improve combustion, improving efficiency and reducing engine emissions will have high scientific and practical significance. In this paper, an experimental study was conducted on four stroke diesel engine driving a generator. The engine is supplied with hydrogen-rich air on the intake charge by integrating an exhaust gas recirculation (EGR) system with a flow of 25 l/min. In this study, the authors focused on the evaluation of specific fuel consumption, thermal efficiency and emission characteristics of engines with different levels of EGR use. Experimental results show that when the rate of using hydrogen increases, the emission level of particles and NOx are significantly reduced.

Taguchi based optimization of diesel engine parameters with blends of lemon grass oil with ZnO

Abstract: An experimental investigation is carried out to analyze the performance and emission characteristics of a compression ignition engine while using Zinc oxide (ZnO) nanoparticles as additive in diesel-biodiesel blends. In the first phase of the experiments, stability of neat diesel and diesel-biodiesel fuel blends with the addition of Zinc oxide nanoparticles are analyzed. After series of experiments, it was found that the blends subjected to high speed blending followed by ultrasonic bath stabilization improves the stability. The performance characteristics are studied using the stable fuel blends in a single cylinder four stroke Zinc oxide acts as an oxygen donating catalyst and provides oxygen for the oxidation of CO or absorbs oxygen for the reduction of NOx. The activation energy of Zinc oxide acts to burn off carbon deposits within the engine cylinder at the wall temperature and prevents the deposition of non-polar compounds on the cylinder wall results reduction in HC emissions. The tests revealed that Zinc oxide nanoparticles can be used as additive in diesel-biodiesel blend to improve complete combustion of the fuel and reduce the exhaust emissions significantly.

Investigations on the impact of EGR with a modified combustion chamber for CI diesel engine using biodiesel

Abstract: The economic growth of the country mainly depends on transportation sector. In this connection petro-diesel consumption has been increased due to wide development of transportation sector. With increase in petro-diesel products there is a serious threat on the reserves of petroleum products (fossil fuels) and pollution levels of environment. This has been thrown a great challenge in front of the researchers working in this domain. To reduce the afore said problems as the petro-diesel products are exhaustive in nature, there is a necessity to find suitable alternative fuel in place of petro-diesel products. Further to reduce the intensity of pollutant levels in the environment also a suitable substitute to be selected. Both these qualities are found in majority of bio diesels. Bio diesel properties are closure to diesel fuel. But the NOx emissions produced with biodiesel are more compared to diesel fuel. Hence, a suitable modification for the existing engine to be carried out to enhance combustion phenomenon and to reduce pollutant levels. In the present work the experiments are conducted with suitable bio diesel, piston geometry and EGR design. With these the investigations are conducted out on four stroke single cylinder water cooled, computerized test rig of CI diesel engine. The performance and emission characteristics are investigated. The results are correlated with base engine and found fruitful, which are presented in the full text.

Combustion analysis of a single cylinder variable compression ratio small size agricultural DI diesel engine run by Nahar biodiesel and its diesel blends

Abstract: This study explores the combustion characteristics of a single cylinder four stroke variable compression ratio direct injection diesel engine run by Nahar biodiesel (BD) and its six different blend...

Euglena Sanguinea algal biodiesel and its various diesel blends as diesel engine fuels: a study on the performance and emission characteristics

Abstract: In this study, the performance and emission characteristics of a single cylinder four stroke diesel engine have been studied by using Euglena Sanguinea algal biodiesel and its various diesel blends...

Emission and Performance Optimization of Marine Four-Stroke Dual-Fuel Engine Based on Response Surface Methodology

Abstract: As the emissions regulations have become more stringent, reducing NOX emissions is of great importance to the shipping industry. Due to the price and emissions advantages of natural gas, the diesel-natural gas engines have become an attractive solution for engine manufacturers. Firstly, in this paper, the NOX emissions prediction model of a large marine four-stroke dual-fuel engine is built by using AVL-BOOST. In addition, the model is further calibrated to calculate the performance and emissions of the engine. Then, the influences of boost pressure, compression ratio, and the timing of intake valve closing on engine performance and emissions are analyzed. Finally, the response surface methodology is used to optimize the emissions and performance to obtain the optimal setting parameters of the engine. The results indicate that the response surface method is a highly desirable optimization method, which can save a lot of repeated research. Compared with the results from manufactured data, the power is increased by 0.55% and the BSFC, the NOX emissions, and the peak combustion pressure are decreased by 0.60%, 13.21%, and 1.51%, respectively, at low load.

Effect of nozzle opening pressure on combustion, performance, and emission analyses of a dual fuel diesel engine

Abstract: In this study, a single cylinder, four stroke, air cooled, direct injection (DI) diesel engine developing a power of 44 kW at a constant speed of 1500rpm was modified to operate on a dual fuel mod

Comparative Study of the Effective Release Energy, Residual Gas Fraction, and Emission Characteristics with Various Valve Port Diameter-Bore Ratios (VPD/B) of a Four-Stroke Spark Ignition Engine

Abstract: In this research, the residual gas, peak firing pressure increase, and effective release energy were completely investigated. To obtain this target, the experimental system is installed with a dynamo system and a simulation model was setup. Through combined experimental and simulation methods, the drawbacks of the hardware optimization method were eliminated. The results of the research show that the valve port diameter-bore ratio (VPD/B) has a significant effect on the residual gas, peak firing pressure increase, and effective release energy of a four-stroke spark ignition engine. In this research, the engine was performed at 3000 rpm and full load condition. Following increased IPD/B ratio of 0.3–0.5. The intake port and exhaust port diameter has a contrary effect on engine volumetric efficiency, the residual gas ratio increase 27.3% with larger intake port and decrease 18.6% with larger exhaust port. The engine will perform optimal thermal efficiency when the trapped residual gas fraction ratio is from 13% to 14%. The maximum effective release energy was 0.45 kJ at 0.4 intake port-bore ratio, and 0.451 kJ at 0.35 exhaust port-bore ratio. The NOx emission increases until achieved a maximum value after that decrease even VPD/B was still increasing. With a VPD/B ratio of 0.35 to 0.4, the engine works without the misfiring.

One-Dimensional Modeling of Mechanical and Friction Losses Distribution in a Four-Stroke Internal Combustion Engine

Abstract: As the road transport accounts between 15%–18% of worldwide CO2 emissions, the automotive sector has a deep commitment to mitigate global warming. Consequently, stricter regulations have been adopted by the European Union and worldwide to reduce that big impact. Approximately, 10% of the energy generated by fuel combustion in the engine is destined to the auxiliaries components activation and the movement of mechanical elements with relative motion between themselves. A reduction on that figure or alternatively a mechanical efficiency improvement can be directly translated on target alignment. The aim of this work is developing a model to predict the mechanical and friction losses and its distribution in a four-stroke direct injection-diesel engine and simulating different strategies, which increment the engine efficiency. A 1D model has been developed and fitted in gt-suite based on the experimental results of a 1.6-L diesel engine. Additionally, a description of the tribological performance has been realized in different parts of the engine where friction is present. Finally, the engine friction maps have been broken down in order to quantify the friction losses produced in the piston ring assembly, crankshaft bearings, and valvetrain.