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Vehicles powered by internal combustion engines correspond to 99.7% of the global fleet. Unfortunately, most of them runs with fossil fuels and contribute with over than 70% of CO and 20% of CO2 emitted to atmosphere. Global climate change has become a major issue and stringent legislation has been forcing the scientific community to seek a feasible solution for this issue. Renewable fuels, hybrid and electric vehicles have been pointed out as the answer for harmful greenhouse gases emissions. This paper demystifies the wrong belief that ICE will be totally replaced by electric vehicles in short and medium time. The zero emission vehicle (ZEV) terminology applied to EV must abolished since it is not true, as 65% of global electricity is generated from non-renewable sources. Despite of being more efficient, hybrid vehicles are still economically unfeasible.

The emission of nitric oxide (NOx) is the most difficult to limit among numerous harmful exhaust gas components. The NOX emission of internal combustion engines is mainly NO, but it will be oxidized into NO2 quickly after entering the air. NO is formed inside the combustion chamber in post-flame combustion by the oxidation of nitrogen from the air in conditions that are dependent on the chemical composition of the mixture, temperature and pressure. The correlation between NO emissions and temperature in the combustion chamber is a result of the endothermic nature of these reactions and can be described by extended Zeldovich Mechanism. The stratified torch ignition engine is able to run with lean mixture and low cyclic variability. Due to lean operation, the in-cylinder temperature of the STI engine is significantly lower than the conventional spark ignited one. This fact lead to a substantial reduction in NOx specific emission.

The transportation sector is responsible for 24% of CO2 global emissions and great effort has been made by the scientific community to replace the use of fossil fuels with renewables. Brazil has committed to implement all obligations provided in COP26 seeking carbon neutrality in the set of economic activities. In this regard, Brazil has agreed in reducing GHG by 50% until 2030. Flexfuel technology was introduced in the Brazilian market decreasing fuel conversion efficiency due to the use of an intermediary compression ratio value, lower in comparison with the best value for engines exclusively fueled with ethanol and higher for gasoline. According to data published by INMETRO, flexfuel engine consumption has increased around 6%. Many European countries have been pointing to the electrification of the light vehicle as a solution to mitigate GHG, which is neither best nor a feasible solution for the future of Brazilian mobility.

The nitrogen oxide (NOx) emitted by the internal engines is an undesirable pollutant and responsible for the photochemical smog when reacts with ultraviolet light from the sun. This smog can cause eyes and respiratory system irritation as also damage plants. The torch ignition system has been proving to be a viable alternative for reducing NOx emissions, and it is one of the main attractions of the system. NOx formation is closely related to the system’s work temperature. Thus, determining the temperature in the pre-chamber is of fundamental importance, whereas the torch ignition system operating at a temperature above the specified, could lead to an increase in NOx emissions, in the probability of detonation and in the probability of pre-ignition, the possibility of limiting performance, an increase in mechanical efforts and deformation/ breakage.

Government regulations and the growing awareness of the general population about the impact caused on nature and human health by the pollutant emission from automobiles have increased the demand for a more environmentally friendly solution for the future of mobility. Considering the high cost of electric vehicles, the negative environmental impact of their battery production due to mining, the long charging time and, above all, the fact that 65% of the global electricity is generated by fossil fuels, the relevance of further developing internal combustion engines fueled with biofuels is unquestionable. Lately, the turbulent jet ignition (TJI) system has been intensively studied as a means to reduce specific fuel consumption (SFC) and pollutant emissions from engines. Both active and passive TJI are endowed with high ignition energy allowing the spark-ignited engine to run with lean mixtures and low covariance of IMEP.

In 2020, 3.6 million of heavy-duty vehicles operate in Brazil transporting 1,548 billion TKU goods and 2,372 million passengers every year. 45.1 billion of liters of Diesel are consumed per year emitting 185.3 million tons of CO2 to atmosphere. Transportation is one of largest sectors of society in CO2 emissions, being responsible of 8.6% of GHG. In Brazil, heavy vehicles predominantly are powered by fossil fuels. Huge efforts have been displayed by the scientific community to mitigate GHG emissions. Brazil has signed the term of COP 26 establishing a goal to reduce GHG emissions in 50% until 2030. Heavy duty vehicles are responsible of emitting 49.9% of CO2 of the transportation sector. The emissions standards of Brazilian legislations have decreased the limits of NOx, PM, CO in 75, 94 and 63% since 2000 were PROCONVE P2 have stabilized the first emissions limits for heavy-duty vehicles.

Direct inject engine provides increased possibilities to work with injection strategies in order to achieve better efficiency. Some ethanol properties such as the higher octane number, the latent heat of vaporization as well as the faster laminar speed made ethanol one of the most promising biofuels. These properties help to achieve knock suppression in a SI engine and therefore allow the use of higher volumetric compression ratio, which is one of the key factors in efficiency improvement. Several studies have showed ethanol as a way to reduce soot formation in direct injection engines as the oxygen molecule reduces the locally fuel-rich region. The use of ethanol contributes significantly to the reduction of total hydrocarbon (THC) and carbon monoxide (CO).

In the actual context, Researchers are making efforts for becoming mobility more sustainable. Whithin it context, the strategy of direct injection of renewable ethanol fuel in spark ignition engines is an interesting alternative for substitution of fossil fuels. In Brazil, the majory part of ethanol fuel production is provenient of sugar cane that has the potential to absorb great quantity of carbon dioxide through the photosynthesis process. The focus of this study was to create a very low computational cost methodology for evaluating the shape of sprays produced by an inwardly opening pressure-swirl injector. The referred injector is to be used in four stroke spark ignition engines for delivering fuel directly inside the combustion chamber. The spray geometry was then predicted by numerical calculations of single droplets trajectories in a purely lagrangian approach. The working fluid injected considered was EXXSOL D60.