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In recent years, the use of ethanol fuel in internal combustion engines has gained importance due to environmental and commercial factors, since ethanol produces lower emission rates at similar performance parameters compared to gasoline fuel. The objective of this study is to evaluate and compare the effects of engine performance parameters on the vibration level of the engine block operated with gasoline and ethanol fuel. The experimental tests consisted of operating an Otto cycle engine on a bench dynamometer under full load conditions varying rotation and correlating the vertical, longitudinal and transverse vibration levels of the block engine with the engine performance parameters. The results showed that the engine vibration level was influenced by engine speed, load, type of fuel and performance parameters of the engine. The combustion process is primarily responsible for the highest level of vibration reached when using ethanol fuel.

Over the years, the application of predictive analysis techniques in internal combustion engines to detect internal component wear and avoid catastrophic engine failures has evolved a lot. Among the most used are the vibration analysis and analysis of lubricating oil. The objective of this study is to investigated the vibrational behavior of an internal combustion engine in function of fuel and the type of technologies incorporated into automotive oils. The results show that the vibration level of the engine increases with the time of use of the lubricating oil and that this increase is very significant when the oil viscosity reaches the minimum value stipulated by the manufacturer. Semi-synthetic and synthetic lubricating oils have similar engine protection characteristics, but synthetic oil protecSt the engine for a longer period of time due to less degradation of chemical properties compared to semi-synthetic.

Lubricating oils for automotive engines have been incorporating important improvements in chemical properties to increase engine performance, reduce fuel consumption and vehicular emissions indices, in addition to increasing the time interval for changing the lubricant itself. The objective of this study is to investigate the vibrational behavior of the block and crankshaft an Otto cycle internal combustion engine operated with ethanol and gasoline fuel as a function of the viscosity and total base number (TBN) of the lubricant. The study consisted of instrumenting the block and the 1st and 5th fixed bearings of the crankshaft with accelerometers to measure the engine vibration intensity and operating the engine on a bench dynamometer in a specific test cycle. Each experiment lasted 600 hours and every 50 hours a block and crankshaft engine vibration level were measured and 100ml sample of lubricating oil was collected to check viscosity and TBN chemical lubricant's properties.

The automotive internal combustion engine is a thermal machine that, from the combustion of the fuel inside the combustion chamber, releases thermal energy for the engine operation and consequently the displacement of the vehicle. A considerable part of this thermal energy is lost and the way to detect this loss is through experimental testing and applying the thermal balance to the engine. This work aimed to perform a thermal balance of the Otto cycle engine involving the energy released due to the gasoline combustion process, power delivered from the engine shaft, energy rate rejected for the cooling system, energy rate rejected for the exhaust system and energy rate rejected to the environment in the form of heat and incomplete combustion. The experiment consisted of making a thermal balance of the engine running with gasoline from experimental data measured on the engine operating on a bench dynamometer varying load and rotation conditions.

Ethanol and gasoline are widely used with fuels in Otto cycle engines. These fuels have different heating power and octane number and the engine behaves differently depending on the type of fuel used. The objective of this study is to measure, compare and investigate the factors that affect the block vibration of an internal combustion engine as a function of the fuel used ethanol or gasoline. The experiment consisted of instrumenting the side of the engine block with an accelerometer to measure the level of vibration intensity of the engine running on a bench dynamometer varying engine speed and load conditions. The results showed that the engine vibration level increases with the increase in engine speed and load. The highest level of vibration was achieved in the region of maximum torque and maximum pressure combustion. The combustion process is mainly responsible for the highest level of vibration achieved with ethanol.

Vibration problems in internal combustion engines produce premature wear on the internal components of the engine, which contributes both to reduce the lifespan of the engine itself as well as cause discomfort to the occupants of the vehicle. Thus, since it is impossible to totally eliminate vibrations from engines, it is important to understand the sources of vibration production and control them to acceptable levels. The general objective of this paper is to measure the vibration in the areas that undergo greater efforts due to the processes of combustion and mechanical forces. These areas are the fixed bearings located to the extremes of the crankshaft. The specified objective of this study is to correlate these levels of crankshaft engine vibration relative to the fuel used, ethanol and gasoline, and assess the influence of lubricant oils on the vibration levels as a function of the viscosity of the lubricant.

When analyzing vibrations in internal combustion engines, it is noticed that the greatest sources of vibrations are generated by combustion and mechanical forces. These forces occur over a wide frequency range and are transmitted to the outer surface of the engine through several paths, such as through the piston mechanism, connecting rod, crankshaft and engine block. As a result of the action of these forces, the external surfaces of the engine are subjected to vibrations of various amplitudes. Vibration problems in internal combustion engines are common due to the wide variety of parts and components that make up such engines. The crankshaft undergoes transverse, longitudinal and torsional vibrations due to the dynamics of the stresses sustained mainly during the combustion phase of the engine.

A burning process in a combustion chamber of an internal combustion engine is very important to know the maximum temperature of the gases, the speed of combustion, the ignition delay time of fuel and air mixture exact moment at which ignition will occur. The automobilist industry has invested considerable amounts of resources in numerical modeling and simulations in order to obtain relevant information about the processes in the combustion chamber and then extract the maximum engine performance control the emission of pollutants and formulate new fuels. This study aimed to general construction and instrumentation of a shock tube for measuring shock wave. As specific objective was determined reaction rate and ignition delay time of diesel, biodiesel and ethanol doped with different levels of additive enhancer cetane number. The results are compared with the ignition delay times measured for other authors.

A burning process in a combustion chamber of an internal combustion engine is very important to know the maximum temperature of the gases, the speed of combustion, the ignition delay time of fuel and air mixture exact moment at which ignition will occur. The automobilist industry has invested considerable amounts of resources in numerical modeling and simulations in order to obtain relevant information about the processes in the combustion chamber and then extract the maximum engine performance control the emission of pollutants and formulate new fuels. This study aimed to general construction and instrumentation of a shock tube for measuring shock wave. As specific objective was determined reaction rate and ignition delay time of diesel, biodiesel and ethanol doped with different levels of additive enhancer cetane number. The results are compared with the ignition delay times measured for other authors.

The problems of vibration and noise from an internal combustion engine are common because of the wide variety of parts and components that make up an internal combustion engine. In recent years engines have evolved considerably in relation to the control of vibration and noise emitted, since these effects reduce the useful life of the internal components of the engine itself and, besides giving discomfort to the occupants of the vehicle. The objective of this work was to identify and describe the main sources of vibration and noise in an internal combustion engine. The methodology used in this work involved instrumentation of an internal combustion engine (Otto cycle), the experimental tests of the engine on a test bench and involved the application of analytical techniques for treatment and analysis of experimental data.

A burning process in a combustion chamber of an internal combustion engine is very important to know the maximum temperature of the gases, the speed of combustion, and the ignition delay time of fuel and air mixture exact moment at which ignition will occur. The automobilist industry has invested considerable amounts of resources in numerical modeling and simulations in order to obtain relevant information about the processes in the combustion chamber and then extract the maximum engine performance control the emission of pollutants and formulate new fuels. This study aimed to general construction and instrumentation of a shock tube for measuring shock wave. As specific objective was determined reaction rate and ignition delay time of ethanol doped with different levels of additive enhancer cetane number. The results are compared with the delays measured for the ignition diesel and biodiesel.