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The ever increasing pressure for more efficient engines, with lower production cost and time has led to the development of advanced simulation tools. Likewise, the experimental development of combustion systems has benefited from computational tools while reducing the necessary experimental time. This paper describes the analysis of combustion performance of a Diesel engine normally used on generator sets. A detailed heat release analysis is performed through one-dimensional simulation software and experimental results, enabling a comprehensive description of combustion parameters of the engine through a simplified study. Brake and indicated values were obtained and analyzed to point out efficiency maps and show the effectiveness of the simulation tool in engine and combustion systems development.

Concerns about global warming, pollutant emissions and energy security have driven research towards cleaner and more environmentally friendly fuels. In the same way as ethanol, butanol is a promising biofuel but with different characteristics such as higher calorific value and lower latent heat of vaporization. It has similar properties to those of gasoline, which makes it a potential surrogate for this fossil fuel. Therefore, the present study proposes a comparison among four different fuels i.e. n-butanol, n-butanol and ethanol blend (B73E27), gasoline and ethanol blend (G73E27), and hydrous ethanol. A single cylinder naturally aspirated research engine with port fuel injection was employed. Engine performance was experimentally evaluated and combustion parameters were determined through reverse calculation based on acquired intake, exhaust and in-cylinder pressure on GT-Power.

The forecast scenarios regarding the environmental pollution raises a question whether the current vehicle emission certification is reliable enough to assure fleet agreement with the legal limits. Type approval tests have been performed on chassis dynamometer in order to evaluate the emission factors and fuel consumption for passenger cars. Standardized procedures such as the FTP-75 proposed in the United States (currently incorporated in the Brazilian legislation) and the Worldwide harmonized Light vehicles Test Cycle (WLTC), a transient driving cycle model designed by the European Union to overcome the shortcomings of the New European Driving Cycle (NEDC), are discussed in this paper. Both cycles were performed in a chassis dynamometer with a flex-fuel passenger car running on ethanol blend (E92W08). The driver, vehicle and fuel were kept constant so the comparison between the cycles would not be compromised.

Wet ethanol is a low cost renewable fuel which often shows challenging ignition in spark-ignited engines. This can be tackled by using non-flame propagating combustion modes like HCCI. This paper shows experimental results of a diesel fueled generator set which recovers exhaust heat from one of the diesel cylinders to promote HCCI of ethanol on other cylinders. Experimental tests provided results of heat release, energy efficiency and a thorough combustion analysis that demonstrate the possibility of this concept which requires minimal changes on the original engine, making possible to retrofit existing units. A three-cylinder four-stroke engine originally fueled with diesel was used. The diesel injection system in one of the cylinders was replaced by an ethanol electronic fuel injection. Inlet heat for achieving HCCI was provided by complete exhaust recycling from one of the diesel cylinders. Stable HCCI combustion was achieved in the ethanol cylinder.

Internal Combustion Engines (ICE) have their use highly disseminated in the most diverse operations. Exhaust gaseous emissions and fuel consumption have been on the scope for decades and therefore the necessity for research on more efficient and lower exhaust emission engines has increased. Considering the cost of equipment and software to develop ICE, the use of computational models is a key strategy to evaluate the behavior of the powertrain/vehicle and lower the instrumentation cost. In this sense, the present work shows the development of an algorithm to obtain a high-resolution crank angle (CA) position of an engine by means of a toothed wheel instead of a high-resolution incremental or absolute encoder. As a result, it enabled the analysis of performance and combustion parameters based on in-cylinder pressure signals acquired through a piezoelectric pressure transducer and the angular position of the crank train referenced by a Hall Effect sensor.

Ethanol with high levels of hydration is a low cost fuel that offers the potential to replace fossil fuels and contribute to lower carbon dioxide (CO2) emissions. However, it presents several ignition challenges depending on the hydration level and ambient temperature. Advanced combustion concepts such as homogeneous charge compression ignition (HCCI) have shown to be very tolerant to the water content in the fuel due to their non-flame propagating nature. Moreover, HCCI tends to increase engine efficiency while reducing oxides of nitrogen (NOx) emissions. In this sense, the present research demonstrates the operation of a 3-cylinder power generator engine in which two cylinders operate on conventional diesel combustion (CDC) and provide recycled exhaust gas (EGR) for the last cylinder running on wet ethanol HCCI combustion. At low engine loads the cylinders operating on CDC provide high oxygen content EGR for the dedicated HCCI cylinder.

The two-zone models are seen as interesting tools for engine simulation. The two-zones, spatially homogeneous, are set during the combustion process. Such models take into account an interface of infinitesimal thickness for the separation between zones. The success of this simulation approach depends on the accuracy of the heat transfer model. Models of heat transfer, in turn, aim to obtain the heat transfer coefficient from the combustion gases in contact with the cylinder walls. Several heat transfer correlations from the literature can be used to obtain the heat transfer coefficient. Eichelberg correlation, which consider natural convection of the combustion gases, along with Woschni, Hohenberg, Sitkei and Annand correlations, which consider forced convection of those gases, were compared in search for the best fit to the experimental data.

Zero-dimensional zonal models are seen as interesting tools for engine simulation due to their simplicity and yet accuracy in fitting or predicting experimental data. For combustion, a common model is a dual zone model, in which two-zones, spatially homogeneous, are set during the combustion process. Such model take into account an interface of infinitesimal thickness for the separation between zones. The success of this simulation approach depends on the accuracy of the heat transfer model. These models aim to obtain the heat transfer coefficient from the combustion gases in contact with the cylinder walls. Several heat transfer correlations from the literature can be used to obtain the heat transfer coefficient.

Biofuels for internal combustion engines have been explored worldwide to reduce fossil fuel usage and mitigate greenhouse gas emissions. Additionally, increased spark ignition (SI) engine part load efficiency has been demanded by recent emission legislation for the same purposes. Considering theses aspects, this study investigates the use of non-conventional valve timing strategies in a 0.35 L four valve single cylinder test engine operating with anhydrous ethanol. The engine was equipped with a fully variable valve train system enabling independent valve timing and lift control. Conventional spark ignition operation with throttle load control (tSI) was tested as baseline. A second valve strategy using dethrottling via early intake valve closure (EIVC) was tested to access the possible pumping loss reduction. Two other strategies, negative valve overlap (NVO) and exhaust rebreathing (ER), were investigated as hot residual gas trapping strategies using EIVC as dethrottling technique.

The prediction of ignition delay times is very useful during the development phase of internal combustion engines. When it comes to biofuels such as ethanol and its blends with gasoline, its importance is enhanced, especially when it comes to flex-fuel engines and the need to address current and future emissions legislations and efficiency goals. The ignition delay time measured as the angular difference between the spark discharge time, as commanded by the ECU and a relevant fraction of fuel mass burned (usually, 2, 5 or 10%). Experimental tests were performed on a downsized state-of-the-art internal combustion engine. Engine speed of 2500 rpm, with load of 6 and 13 bar IMEP were set for investigation. Stoichiometric operation and MBT or knock-limited spark timings were used, while valve overlap was varied, in order to address the effects of scavenging and residuals on ignition delay times.

The activities developed by the Society of Engineers of Mobility (SAE) are important sources of knowledge and technological updating for the industry and for the academic environment. Through annual student events, the association has become a present and active icon for the market, which generates and disseminates knowledge for Brazilian and international mobility professionals. Thus, the article presents, in a didactic and complete way, a reference model for the Mini-Baja Development Process (MBDP), structured and systematized, for conducting and professionally managing the process to the participating teams. Thus, the model provides students, teachers, and members of the business sector a support to reflect on the difficulties and contextualization's encountered throughout the management of the team in the prototype off-road.

The use of green hydrogen as a fuel for internal combustion engines is a cleaner alternative to conventional fuels for the automotive industry. Hydrogen combustion produces only water vapor and nitrogen oxides, which can be avoided with ultra-lean operation, thus, eliminating carbon emissions, from a tank-to-wheel perspective. In this context, the aim of this study is to investigate the influence of hydrogen injection timing and duration on the homogeneity of the hydrogen-air mixtures. Computational fluid dynamic (CFD) simulations were performed to analyze the distribution of air-fuel ratios along the engine's combustion chamber. The simulation software was CONVERGE 3.0, which offers the advantage of automatic mesh generation, reducing the modeling efforts to adjusting the operating conditions of the studied case. Before comparing the injection parameters, a mesh independence test was conducted along with model validation using experimental data.

The current quest for clean and renewable fuels has prompted the appearance of several bio-mass fuel alternatives. Ethanol is a renewable biofuel obtained from different agricultural crops. The main production process to obtain anhydrous ethanol consists of crop production, mashing and cooking, fermentation, distillation and chemical dehydration. Some attractive characteristics of ethanol as a clean energy source is the CO2 absorption through photosynthesis during the crop plantation phase and positive ethanol life cycle energy balance. Even though, ethanol production cost is still relatively high when compared to fossil fuels. Knowing that a large energy amount is spent in the distillation phase, the use of hydrous ethanol as fuel, with high water content, can be economically attractive. This paper compares the use of high water-in-ethanol volumetric content fuel, varying from 5% to 40%, in a naturally aspirated 0.668-L single-cylinder port-fuel injected spark-ignited engine.

Global warming and pollutant emission concerns have been driving research towards cleaner and environmentally friendly fuels. Like ethanol, butanol is a promising biofuel with characteristics such as higher calorific value and lower latent heat of vaporization. Due to its similar properties to those of gasoline, butanol stands as a potential gasoline surrogate. Butanol can be produced from through the ABE (acetone–butanol–ethanol) fermentation process, which uses bacterial fermentation to produce acetone, n-Butanol, and ethanol from carbohydrates such as starch and glucose. This work presents the experimental results of a single-cylinder spark ignition research engine equipped with port fuel injection. Several compression ratios were compared via spacer rings. Fuels as n-butanol, hydrous ethanol (E95W05) and their blends were evaluated in comparison to primary reverence fuel (isooctane).

Due to the ever growing environmental concern regarding global warming and CO₂ emissions, the use of renewable fuels has become increasingly important. Thus, substituting fossil fuels such as diesel by ethanol from sugar cane can be a good alternative. There are, however, several ways of performing it. One of the simplest methods is to use fumigated ethanol with an electronic fuel injection system, operating in dual fuel mode with the original diesel injection, substituting part of the fuel by ethanol. This paper demonstrates the effects of using fumigated ethanol on performance of a standard power generation 4-cylinder turbocharged diesel engine. The research combines simulation results with experimental validation. Initially, a one-dimensional computational model of the original engine running solely on diesel was created and validated for several power levels.

This paper presents the development of an ethanol fueled high performance engine for drag racing. Through the use of a specific software (AVL Boost) it was possible to model and simulate the performance of the engine being developed. The initial parameters required for modeling and the geometry of the various engine components were obtained by direct measurements and data from the literature. Model validation was achieved by comparing simulation results with data found in literature. After that, various engine configurations had been simulated, changing design parameters in order to optimize engine performance. The analysis of simulation results enabled the selection of different components to be manufactured or purchased in order to achieve a high-performance engine for use in drag race competition, with improved torque and power.

In order to further explore the potential of hydrogen as an alternative fuel, this study aims to validate a computational fluid dynamics model for hydrogen combustion in a port fuel injection spark ignition engine. The engine operates at 1800 rpm with a compression ratio of 10:1, under two lean combustion conditions: excess air ratios of 2.5 and 1.7, at full and part load, respectively. The simulations were performed using the CONVERGE 3.1 software and the C3MechV3.3 reaction mechanism. The predictions were then compared with experimental data to assess the accuracy and validity of the model, enabling the comparison of different lean operating conditions to evaluate important combustion characteristics, such as flame development, apparent heat release and NOx formation. The tested model successfully validated the two experimental conditions, accurately adjusting the in-cylinder pressure profiles for both cases of lean hydrogen mixture combustion.