EFFECT OF AMBIENT PRESSURE, OVERALL INPUT EQUIVALENCE RATIO AND RESIDENCE TIME ON CARBON PARTICULATE FORMATION AND OXIDATION IN A CONFINED SPRAY FLAME

摘要

The paper uses a modified, rapid compiling, in-house spray-combustion code to calculate soot concentration distribution profiles within the combustion chamber of a high-pressure spray burner. The code is first assessed by comparison with the commercial code STAR-CD for gaseous product species mole fractions. It is then used with three available soot-formation models and two adaptations of a soot-oxidation model to calculate net soot concentration, throughout the combustion chamber, under different operating conditions. Input mixture ratio, combustion pressure and oxygemnitrogen ratio, in the oxidiser, are varied to produce results at constant pressure, constant equivalence ratio or constant mass flow rate and residence time respectively. The results are presented as property distribution maps relative to the geometry of an experimental high-pressure combustion chamber and results of mean exhaust values are compared with experimental data at the same conditions.