Advanced Design Optimization of Combustion Equipment Using Sculptor with CFD Tools

Traditional optimization studies on computational fluid dynamic (CFD) models entail changes in geometry
and consequent regeneration of computational grids. Depending on the extent of spatial discretization,
these changes may be computationally intensive and prove redundant in a computational time frame.
SCULPTOR® from Optimal Solutions Software has provided arbitrary shape deformation (ASD) tools that
allow 3D shape deformation (i.e. morphing without the need of CAD parameters and without remeshing)
of the computational mesh as a result of detailed changes in geometry, allowing efficient, detailed,
optimized analysis of CFD models. The case at hand is an extension of advanced burner optimization
performed on the standard burner engineering laboratory design, where SCULPTOR was effectively
utilized to optimize flame stability for biomass gasification (Smith and Landon, 2013). Further to a base
design, this study investigates the effect of changing the annular location of secondary air inlets peripheral
to the primary air inlet in a biomass gasifier, as also a change in the diameter of secondary air inlets;
affecting swirl, and analyzes the resulting change in flame temperature, recirculation zones and gas phase
flow instabilities. From the five cases studied, it was observed that the two secondary locus change cases
and the geometry change to the combustor produced estimates (especially for outlet major species mole
fractions) very close to the experimental results furnished by Kobayashi et al. (2009).