Abstract
A two-zone combustion model, in which cylinder volume was separated into combustion and non-combustion zone to simulate general diesel combustion phenomena, was developed to investigate the current status of inhomogeneous (diesel) combustion compared with ideal homogeneous combustion from the instantaneous specific heat ratio variation and corresponding indicated thermal efficiency view point. The computed results were compared with experimental results by means of a single-cylinder engine, and suggested the potential of further thermal efficiency improvement by further diluting and homogenizing the combustion zone, particularly during isobaric combustion phase.
