FKFS Veranstaltungen

2025 Stuttgart International Symposium
on Automotive and Engine Technology

3. - 4. Juli 2025

Session: Hydrogen II | | 09:30 - 10:00

New Horizons of Cylinder Mixture Formation in Direct Injection Hydrogen Combustion Engines.

Olaf Weber, Schaeffler Technologies

First hydrogen combustion engines will go into production with port-fuel injection, based on Diesel engine hardware. Direct injection concepts might represent the second generation of mixture formation systems. Challenges like injection nozzle design and incomplete mixture formation for highest levels of homogeneity are already well known. Market participants are improving these kind of product properties as rich areas generate locally high NOx and possibly provoking knocking conditions. This paper will discuss an injection concept to increase the homogeneity index of direction direct injection concepts with a consequence of lower NOX and/or higher torque output at the borderline air/fuel/ratio of app. 2.4. The enabler is an injector with variable flow patterns depending on needle stroke and pressure ratios. Different application cases will be discussed to understand the NOx reduction potential.