Based on a single-cylinder test machine

the effect of excess air coefficient on the performance of turbulent jet ignition(TJI) engine was studied. The optimal operating range of TJI engine was explored by analyzing the engine performance

combustion and knock characteristics and was compared with spark ignition(SI) combustion method. The results show that TJI can effectively increase the instantaneous heat release rate

extend the lean burn limit of the engine

and shorten the ignition delay and combustion duration of the in cylinder mixture. At the same time

fuel economy can be improved. Under lean burn conditions

nitrogen oxides emissions are extremely low. In terms of knocking

as the ignition advance angle increases

the multi-point ignition effect of the jet flame will produce significant pressure oscillations in the cylinder

and continued increase will induce spontaneous combustion of the end mixture. Therefore

the TJI detonation cylinder pressure shows a two-stage pressure oscillation

and the maximum amplitude of pressure oscillation concentration is high. Increasing the excess air coefficient can reduce the amplitude of the TJI maximum amplitude of pressure oscillation

making the engine work in slight knock or no knock state.