Natural Gas Partially Stratified Lean Combustion: Analysis of the Enhancing Mechanisms into a Constant Volume Combustion Chamber

摘要

The use of ultra-lean mixture natural gas fueled Internal Combustion Engines has been widely accepted to improve thermal efficiency and reduce exhaust emissions. This is mainly due to the intrinsic features of natural gas such as the wide availability and lower carbon content. Other advantages may occur running the engine under lean operating condition, as for example the lower flame temperature, the higher volumetric efficiency and compression ratios achievable, together with the opportunity of load control by varying the mixture equivalent ratio. Issues related to combustion stability and increase of CoV may however arise at leaner conditions.