|
Coal combustion Model
The important features of the coal combustion model are:
- It is based on the finite-volume philosophy for the numerical solution of the partial differential equations.
- The turbulence effects are simulated via the two-equations (k-e) model.
- A two-step kinetics scheme is employed to simulate the gas-phase combustion.
- A Lagrangian formulation is employed for the particulate phase. The effect of particles on the gaseous phase is accounted
for by the Particle Source In Cell (PSIC) method, which treats the particles as sources of mass, momentum and energy.
- The particles are assumed to consist of coal, char, and ash. The particle reaction model includes coal devolatilization and
char oxidation.
- The radiation heat transfer is modeled through the six-flux model.
- It uses a global reaction mechanism for predicting pollutant formation.
The model has been applied to coal-fired furnaces and cement kilns. The applications have included:
- study of the effect of operating conditions on NOx formation and unburned carbon
- assessment of new strategies for NOx reduction
- effect of burner configuration on performance
Temperature distribution in a cement kiln
|
