Intrinsic Flame Instabilities for Engine Control: Translating Hydrogen Combustion Physics into Control Strategies

Objectif

Hydrogen internal combustion engines offer carbon-free power for applications where electrification is difficult. Ultra-lean operation enables high efficiency and low nitrogen oxides (NOx) emissions, however, under these conditions, intrinsic flame instabilities (IFIs) caused by differential diffusion of hydrogen and heat, significantly influence burning rate, pollutant formation, and thermal efficiency. These effects have a huge impact but cannot be reliably predicted by current industrial workflows that combine high-fidelity computational fluid dynamics (CFD) with reduced-order engine simulations. As a result, hydrogen engines are calibrated conservatively, and thus the efficiency potential remains underexploited. To enable IFI-enhanced combustion control, the PoC will translate insights from the ERC Advanced Grant on IFI–turbulence interactions into an engine-relevant design and optimization framework for control strategies (IFI-2-CTRL). IFI-2-CTRL has two main objectives. First, a computationally efficient, tool-independent reduced-order models will be developed and provided as an open modeling framework for engine design and pre-calibration. Second, the developed model will be used to demonstrate a workflow for engine optimization, in which IFI are actively tailored through key control parameters and validated through experimental investigations on multiple engine test benches. Key control parameters (e.g. injection strategy, residual gas control via exhaust gas recirculation (EGR) or valve timing, fuel-blends) will be explored, including transitions between ultra-lean part-load and stoichiometric high-load operation. IFI-2-CTRL delivers a transferable modeling framework and a validated workflow that actively uses IFI as a controllable performance lever, transferring IFIs from a specific hydrogen combustion phenomenon into a controllable engine design parameter, unlocking the potential for higher efficiency and near-zero NOx emissions.