To comprehend the cause-and-effect sequence of cyclic variations in spark-ignited internal combustion engines designed for hydrogen-based implementations, a thorough investigation into turbulence phenomena becomes imperative. In the context of hydrogen combustion, transport phenomena exhibit considerable complexity, wherein differential diffusion and thermal instabilities alter fluid flow behaviour, consequently impacting turbulence.
Employing high-fidelity simulations allows for the reliable integration of supplementary terms that account for these effects. By resolving statistical turbulence quantities, it becomes possible to trace the diverse phenomena contributing to cyclic variations. Large Eddy Simulations strike a balance between computational resource allocation and result quality, essential for accurate turbulence prediction. When the prediction of turbulent properties is assured, it becomes feasible to correlate them with cycle strength.
The existing models and methods within LES-based simulations must undergo calibration and further refinement to consistently predict turbulence with utmost reliability and precision, especially for hydrogen-based systems with the aforementioned additional challenges. This endeavour necessitates concurrent validation of numerical results, which is only possible by a strong cooperation between researchers.