Etude de la combustion de gaz de synthèse issus d'un processus de ...

Numerical simulation of a syngas-fuelled engine
mixture due to wall interaction. The entire flowchart of the developed code is shown in
figure 6.2.
It requires as input data the engine geometric characteristics, engine speed, fuel–air
equivalence ratio, combustion chamber walls temperature, compression ratio, ignition
delay, and temperature and pressure of charge at IVC event. It is assumed that during
compression the cylinder content, consisting of air–fuel mixture and any residual
gases, comprises one zone. From the start of combustion, multiple burned zones
(whose number is user-defined) are sequentially generated, with the latest-generated
burned zone being separated from the unburned zone by an infinitesimally thin flame
front. The multi-zone approach is retained throughout the expansion phase, i.e. from
the end of combustion until the EVO.
tel-00623090, version 1 - 13 Sep 2011
All zones considered are assigned spatially uniform pressure, temperature and
composition at any instant of time. During all phases, the pressure is uniform
throughout the cylinder at any instant of time. It is noted that the model, being zerodimensional
in nature, does not predict geometrically the actual position of the flame
front and the various zones inside the cylinder. Rather, simulation follows purely the
thermodynamic approach.
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