Advances in 1D thermo-fluid dynamic simulation of SI hydrogen-fueled engine

Abstract

This work has the objective to describe the improvement introduced in the 1D thermo-fluid dynamic simulation code developed to simulate hydrogen-fueled Internal Combustion Engines. Two main topics have been analyzed. The first regarding the simulation of unsteady flows in the whole intake and exhaust system and the injection process of the fuel, considering a mixture of ideal gases as working fluid with specific heats depending on both gas temperature and composition. The second one focused on the combustion process, where the correlation-based approach used to compute the laminar flame speed for the homogeneous air-hydrogen mixture has been substituted by a Tabulated Kinetic approach. New correction factors that account for surface instabilities have been also added to obtain a more accurate prediction of the combustion process. The modifications introduced have been validated against experimental values comparing in-cylinder pressure trends, intake and exhaust instantaneous pressure pulses taken at different locations. Finally, the results obtained from the simulations of a novel hydrogen-fueled heavy-duty engine are presented.