The Digest’s 2025 Multi-Slide Guide to Heavy-Duty H2 Combustion

Sandia National Laboratories is advancing hydrogen internal combustion engines (H2ICE) for hard-to-electrify sectors, targeting 2024-2027 market entry. Key findings: increased swirl improves H2 mixing, yet cyclic variability remains. Crucially, hydrogen significantly delays hydrocarbon auto-ignition, providing new insights into oil pre-ignition. Pre-chamber fueling with H2 reduces cyclic variability and enables ultra-lean operation, outperforming natural gas. This research tackles pre-ignition and NOx barriers for cost-effective, high-power H2 engines.