The present work was devoted to assess the chemical kinetic modelling of bio-syngas combustion. Three
reaction mechanisms (the Gas Research Institute-mechanism GRI 3.0, its skeletal version DRM22 and
Heghes’ C1–C4 mechanism) were considered for that purpose along with series of ignition delay measurements
relevant to the burning of bio-syngas. For experiments involving methane with and without
considerably smaller quantities of added hydrogen, the measurements are generally overpredicted by
Heghes’ mechanism but underpredicted by the GRI and DRM mechanisms. Experiments involving various
blends of the bio-syngas constituents were also simulated. The strong discrepancies present for high
pressures and temperatures and low pressures and temperatures could be correlated to five reactions
which are only influential under those conditions, four of which involving HO2. The effects of variations
in the bio-syngas composition on combustion were numerically investigated by using the GRImechanism.
Globally it was found that an increase in any of the constituents goes hand in hand with
higher amount of CO released. The ignition delay is either shortened or left unchanged as the initial
concentration is increased except in the case of methane where it is raised. The results were in good
agreement with experimental observations made elsewhere.