The transient characteristics of an engine are one of the important evaluation indexes
related to the operability of a vehicle. We have developed a diesel engine zero-dimensional
combustion model that can calculate the engine combustion cycle in a short amount of time on the
order of several seconds based on combustion simulation models that we have established. This
paper presents a simulation technology that utilizes this zero-dimensional combustion analysis to
accurately estimate the transient characteristics of an engine. The use of this simulation model
allows an engine system to be optimized before the production of a prototype through the
evaluation of various vehicle operating patterns, and therefore contributes to shorter vehicle
development times.