Abstract
International agreements and the urgency for the reduction of gases that contribute to climate change have sparked the search for alternative fuels of satisfactory qualities to fulfil the demand posed by internal combustion engines. In spite of this, it is indeed worth analysing their behaviour at every stage on one side or the other and to observe the contrasts depending on the design of the combustion chamber. For this reason, we focus on the injection of three fuels diesel, hydrogen and methane chosen because of their contrasting physical and chemical properties. Their behaviour is compared and its velocity is focused on. In order to perform it, a numerical simulation performed using ANSYS and selected mathematical models coherent with the physical phenomena dictated by the injection of fuel, turbulence, mass conservation, the atomization process. The values for the initial conditions of the study were drawn from literature and data from real experiments dependent on the velocity, pressure and temperature. Results showed that the behaviour was better suited the deeper combustion chamber, and that methane entered with a greater velocity corresponding to being more that %10 than even other fuels, thus favouring the filling of the combustion chamber and consequently assuring better combustion. Their behaviour reflects the way they should be treated and shows that temporary alternatives can ensure a clean transition for the automotive sector.