PR179-22206-R01 Prechamber Air and Fuel Premixing Proof of Concept

This study investigates the feasibility of injecting a premixed air and fuel charge into the precombustion chamber (PCC) of a Cooper-Bessemer GMV-4TF 2-stroke lean-burn natural gas engine. The primary ob-jectives are to enhance combustion stability, reduce emissions, and address the challenges associated with stratification within the PCC. Computational fluid dynamics (CFD) simulations were conducted to evaluate both ideal and practical premixed scenarios. The ideal premixed scenario aimed to achieve improved ho-mogeneity and faster flame propagation. Low-pressure premixed injections were tested to examine the ef-fects of near-stoichiometric mixtures on mixture homogeneity, while high-pressure premixed injections focused on reducing stratification within the PCC.

Key metrics assessed included homogeneity of the air-fuel mixture, flame propagation speed, mass transfer between the PCC and the main combustion chamber (MCC), and emissions performance. Adjustments to PCC fuel injection timing, mass flow rates, and other critical parameters were explored throughout the simulations. The findings provide insights into the impact of premixed injection strategies on combustion dynamics and emissions characteristics of large-bore natural gas engines.