Feasibility of the Direct-Injection SI Hydrogen Engine at Various Injection Pressures

Abstract

From the consideration of practical use of the direct-injection spark-ignition (DISI) hydrogen engine, the output performance and combustion processes are systematically investigated for various injection and ignition timings at different injection pressures. It is shown that almost the same thermal efficiency can be achieved even at a lower injection-pressure condition as long as the injection and spark timings are adequately controlled with engine loads. Based on the obtained results, the strategy for selecting the parameter of operating conditions are proposed and then the feasibility of DISI hydrogen engine are demonstrated.