Numerical investigation of pre-chamber holes diameter geometry on combustion parameters in a hydrogen-powered Turbulent Jet Ignition engine.

The search for substitutes for conventional fuels leads to the use of non-hydrocarbon fuels or synthetic fuels. One of them is hydrogen. The use of hydrogen in combination with a two-stage charge formation system leads to the combustion of lean (> 1) or very lean (> 3) charges. The simulation tests carried out were aimed at determining the best configuration of the chamber connecting the pre-chamber with the main combustion chamber. Three variants of the diameter of the holes connecting the chambers were selected (d = 0.5; 1.0 and 1.5 mm) in combination with different fuel doses fed to the pre-chamber. A passive chamber (qo_PC = 0 mg) and an active chamber (qo_PC = 0.4 and 1.2 mg) were used with a constant fuel dose to the main chamber (qo_MC = 6 mg). The research was conducted using AVL Fire 2022.1 software using the moving mesh of the LDV engine. Based on the simulation work, the most favourable conditions for conducting the process were determined, taking into account the thermodynamic effects of the process and acceptable levels of nitrogen oxide concentration. The resulting correlation maps of chamber hole sizes and fuel doses supplied to the prechamber can serve as a preliminary basis for selecting control options for hydrogen combustion in the TJI system. [ABSTRACT FROM AUTHOR]