Numerical analysis of particle-laden flow in coal combustion using
This work presents a large-eddy simulation of coal combustion at the
down-fired self-sustanied oxy-fuel combustor (OFC) which includes the
multi-physics phenomena: turbulent flows, particle flow, heat transfer,
coal combustion and ash particle deposition. This modeling work also
includes a dynamic ash deposition model coupled with the heat-transfer
model for the solid surface. This work mainly analyzes the time and
length scale of the flow field. Effects of unresolved turbulent scales
on the particle motions are also analyzed by the Stokes number analysis
based on the subgrid-scale turbulence. Overall, results of this approach
are tested against experimentally measured data at this facility.
Results from the OFC simulation show that the averaged gas temperature
and deposition rates agree within 5\% and
28\%, respectively, with the measured data. The
presented model can be used to simulate coal combustion in the
industrial-scale pulverized coal boiler.