Soot production rate calculations at elevated pressure in a methane-air jet diffusion flame

In this study, a cylindrical 2-D confined coflow methane/air jet diffusion dame was numerically simulated using a reduced 8-step gas phase chemical ki netics mechanism involving 12 major species. The soot model employed a 4-st ep reduced reaction mechanism and radiation from gas products and soot was modeled using the S-6 discrete ordinates method. The flow field and major s pecies concentrations from the simulation were compared with experimental d ata for atmospheric pressure conditions. Higher pressure simulations were p erformed which showed that the increased density at elevated pressure resul ts in a higher soot concentration. Although at increased pressure both the rates of particle nucleation and agglomeration increased, the net rate for the soot particle number density decreased, resulting in lower particle num ber densities at higher pressure as compared with atmospheric conditions. I t was also shown that the environment pressure affected the radiative heat feedback to the fuel base through the soot concentration.