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Speed Recovery is an important performance metric for vehicles and can directly affect passenger safety. In situations such as overtaking, a quick response from the vehicle can be crucial to avoid accidents. In this study, a conventional light vehicle was tested using seven fuels with different concentrations of ethanol, gasoline, and water to evaluate its performance through speed recovery tests on a chassis dynamometer. The SAE J1491 standard was used to conduct the tests third and fourth gears and two different speed ranges for each gear, from 40 to 80 km/k and 60 to 100 km/h. The results indicated that pure anhydrous ethanol (E100) showed the best performance, which can be attributed to its high-octane rating and greater calorific value compared to gasoline. In addition, the use of pure anhydrous ethanol can contribute to greater energy efficiency and reduced emissions of polluting gases, which is important for the sustainability of the automotive industry.

Currently, several studies are being carried out to replace diesel oil with alternative fuels in compression ignition engines. Ethanol is a strong candidate, thanks to its extensive feedstock, low emissions and low cost. Although it also has easy adaptability to engine technologies, there are some difficulties that need to be eliminated regarding its direct use in compression ignition engines (diesel cycle). The present work aims to evaluate the ignition delay of ethanol/peg 600 blends in a four-stroke compression-ignition engine, in relation to maximum pressure and maximum rate of pressure rise under different experimental conditions. Parameters such as engine speed, load and compression ratio, in addition to fuel injection advance and percentage of additive were analyzed. For this study, a code was developed in Matlab computer software capable of analyze data collected through Indicon-AVL, to tests carried out at the Institute of Mobility and Sustainable Energy (IMES - PUC-Rio).

The world recognizes that the main source of energy used in transportation is diesel oil since it is economical and efficient; however, unfortunately, it is not a renewable resource and pollutes the environment. Today, although n-butanol has been used in blends with diesel oil with great results, there is still dependence on the use of fossil fuels. Hence, the effects of n-butanol as an ignition improver for hydrous ethanol were studied for its properties and the fact that this fuel alcohol may be produced by renewable sources, making it possible to replace diesel oil with a biofuel. To study the combustion characteristics of the ethanol/n-butanol blend, a rapid compression machine was used under different test conditions (compression ratio and start of injection). The mass fractions of n-butanol used in the blends were 10% and 15%, and the test results were compared with those of other fuels, i.e., diesel oil S10 and an ethanol/additive blend, developed by SEKAB and named ED95.

Fossil fuels and biofuels usage in internal combustion engines are the main source for vehicular propulsion. This justifies the intense worldwide research and development to comply with the challenges of increasing efficiency and emissions reduction. The modeling of commercial fuels and engine combustion processes presents great challenges. There is also the need to better understand how different fuel components interact and influence engine combustion and performance parameters. In previous works, components selection and engine dynamometer tests were done to identify representative surrogate fuels for commercial Brazilian gasoline. It was concluded that formulations with n-heptane, iso-octane, toluene and ethanol can be used to model oxygenated gasolines. Methodologies were implemented to evaluate the influence of the fuel components on fuel properties and several engine combustion and performance parameters.

Gasoline is a complex mixture, composed of hundreds of different hydrocarbons. Surrogate fuels decrease the complexity of gasoline and are being used to improve the understanding of internal combustion engines (ICEs) fundamental processes. Computational tools are largely used in ICE development and performance optimization using simple fuels, because it is still not possible to completely model a commercial gasoline. The kinetics and interactions among all the chemical constituents are not yet fully understood, and the computational cost is also prohibitive. There is a need to find suitable surrogate fuels, which can reproduce commercial fuels performance and emissions behavior, in order to develop improved models for fuel combustion in practical devices, such as homogeneous charge compression ignition (HCCI) and spark ignition (SI) engines. Representative surrogate fuels can also be used in fuel development processes.

Over the past decades, researchers from different countries that produce oil or not, have intensified their research in order to develop more efficient systems. It is not unknown to the world that the main source of energy used in transport is the diesel oil, to be more economical and more efficient. For this reason, various sectors of transport and fuel producers are developing new technologies in order to replace fossil fuels with other renewable sources. Nowadays it is possible to find on the market engines that run on blends of diesel and other renewable fuels and systems that work with mixtures of ethanol and additives. To be able to use ethanol in compression ignition engines, the main problem to be overcome is the poor flammability of the ethanol under compression ignition conditions. This problem is generally attributed to the high enthalpy of vaporization of ethanol and the need for higher autoignition temperatures when compared to diesel.

Gasoline is composed of hundreds of components. The fuel properties can present a wide range of variation, depending on the formulation. Commercial fuel specifications differ from country to country, based on the features of each market. Also, fuels for some specific engine applications can differ widely from commercial fuels. For the next decades it is expected that the fossil fuels and bio-fuels usage in internal combustion engines remains to be the main source for vehicular propulsion. This justifies the intense worldwide research and development to comply with the challenges of increasing efficiency and emissions reduction. In this context the fuel can play an important role, mainly when there is the possibility to optimize fuel formulation, engine design and engine calibration for the desired application.

Commercial gasoline is composed of hundreds of hydrocarbon components. Surrogate fuels that decrease the chemical and physical complexity of gasoline are being used to allow a better understanding of the processes involved in the interaction between fuels and internal combustion engines (ICEs). Based on previous published works about methodologies for fuel development using surrogate fuels, the aim of this paper is to present further results on the effect of individual components and fuel fractions on the combustion and performance parameters of spark ignition engines. SI engine dynamometer tests were conducted using ten mixtures of iso-octane, toluene, n-heptane and ethanol. Response surface models were statistically developed to analyze the interactions between fuel components, fuel properties and engine performance.

This study presents the evaluation of the energy efficiency of a series hybrid electric vehicle through the theoretical development of two electric propulsion systems and an experimental study of fuel consumption of the original vehicle. The experimental analysis was done by a test setting, consisting mainly of a chassis dynamometer, an autopilot system and a fuel flowmeter, all connected to the data acquisition system. In this study it was developed two theoretical models of propulsion systems for Series - HEV. The first one consists of four in-wheel motors and the second one consists of two in-wheel motors on the rear axle. There are various methods for embedding a motor in the wheel. It is necessary to consider the weight, power and transmission efficiency. In the theoretical model it was considered a cycloidal reducer, which allows a reduction of 3:1 to 119:1 in one stage with an efficiency of 93%, together with a brushless DC motor, which has a high power density.

Gasoline is a complex mixture that possesses a quasi-continuous spectrum of hydrocarbon constituents. Surrogate fuels that decrease the chemical and/or physical complexity of gasoline can be used to enhance the understanding of fundamental processes involved in the interaction between fuels and internal combustion engines (ICEs). The aim of this paper is to present methodologies for fuel development and show how surrogate fuels can be used to investigate the effect of individual components and fuel fractions on fuel properties and the performance of commercial engines. For this purpose, experiments were designed and SI engine dynamometer tests were conducted using ten mixtures of iso-octane, toluene, n-heptane and ethanol. Response surface models were statistically developed to analyze the interactions between fuel components, fuel properties and engine performance.

Combustion images are not simple to be obtained in conventional engines. Therefore, some experimental apparatus, such as a rapid compression machine (RCM), are useful to conduct this kind of study. Imaging techniques allow flame front propagation analysis, which is a very important parameter to understand engine performance, using different fuels and also to generate data to improve fuel modeling in engine simulation softwares. A RCM was adapted to operate in a spark ignition engine mode. It was used to obtain cylinder pressure measurements of gasoline-ethanol combustion synchronized with high-speed photos of flame propagation. Contour plots of the flame front profiles, assumed to be spherical, were used in successive frames to calculate the propagation speeds toward the cylinder walls. So, it was possible to correlate images, pressure curves and flame speeds of gasoline-ethanol blends.

Rapid Compression Machine (RCM) is an experimental tool developed to study engine combustion parameters. The RCM used is a pneumatically and hydraulically driven device which reproduces a single combustion shot, considering a compression and a partial expansion stroke. This paper describes RCM adaptations made in order to run Otto cycle tests using Brazilian regular gasoline (E25) [1]. These adaptations enable pre-vaporized air-fuel mixture combustion tests, representative of port fuel injection engines, by using a gasoline direct injection (GDI) injector. It is also presented RCM piston displacement and cylinder pressure comparisons to a real engine and RCM comparative results for different spark timings and compression ratios. These results show that RCM reproduced satisfactorily piston displacement and pressure curves during the combustion shots, when compared to real engine curves.