3D CFD analysis of Mixture Formation in Direct-Injection Hydrogen-fueled Internal Combustion Engines

The European Green Deal for halving greenhouse gases emissions by 2030, compared to those of 1990s, and the resulting conversion in road transport from 2035 imply the need for the automotive field. Hydrogen-fueled internal combustion engines show a good potential to satisfy the transition towards the carbon neutrality. In particular, direct injection of hydrogen in spark-ignited internal combustion engines have great efficiency potentialities, nonetheless the design optimization of the injection systems needs extensive analysis for the evaluation of the hydrogen-air mixing processes under different engine operating conditions. Transient simulations of the gas-exchange process and fuel injection and mixing are fully described within this paper for two different commercial CFD codes namely, AVL-Fire and Ansys-Fluent. Both codes use the finite-volume approach to discretize the governing equations. Numerical results from the two commercial codes have been compared against the experimental data provided by the Argonne National Laboratories in terms of contours of fuel mole-fractions and velocity-field vectors, resulting from applying laser-based techniques on an optically accessible, single-cylinder engine.