Saastamoinen [16] has studied the modelling of wood gasification
in an updraft mode. In this, gasifier was operated by lowering the air
rate beyond a critical value increasing the bed height without a limit.
The cross draft mode gasifier has a high-energy release rate per unit
area due to high inlet air velocity. If long stick wood is added on top of
the burning charcoal, it will be pyrolysed by the heat, giving a mixture
of gases and volatile condensable compounds. As they are generated,
the charcoal is replenished, so that a steady state can be reached by