Effect of Start of Injection in a Hydrogen-Fueled DISI Engine: Experimental and Numerical Investigation

Abstract

<div class="section abstract"><div class="htmlview paragraph">Nowadays, hydrogen is one the most interesting candidates for fuel for internal combustion engines as an alternative to fossil fuels, in order to reduce GHG emissions.</div><div class="htmlview paragraph">In this paper, the authors have, firstly carried out an experimental investigation on a single-cylinder engine fueled with hydrogen and equipped with a high-pressure direct injector. The experimental campaign shows that the Start of Injection (SOI) has a remarkable effect on the mixture combustion characteristics.</div><div class="htmlview paragraph">Secondly, the software CONVERGE was used to set up a comprehensive 3D CFD model to investigate these engine operating conditions, starting from an injector validation in a constant volume vessel and then simulating the engine cycle including injection, combustion and knock modeling. The combustion model makes use of detailed chemistry to predict the laminar flame speed and auto-ignition delay of the mixture.</div><div class="htmlview paragraph">The simulations show a remarkable difference in terms of mixture homogeneity between the three cases. Moreover, the predicted pressure inside the cylinder during the combustion phase is in agreement with experimental pressure traces.</div></div>