Scaling of coflow flames at constant reynolds and grashof numbers with application to sooting flames at elevated pressure

Laminar coflow diffusion flames are widely used to study soot formation at elevated pressures. Experimental studies of such flames are conducted at a constant mass flow rate (constant Reynolds number) with increasing pressures. As pressure increases, the flame becomes narrower as a result of gravity. The change in flame shape results in important modifications to the mixing field, which in turn has an effect on soot formation. Therefore, the increase in soot volume fraction across flames with increasing pressure is affected by hydrodynamics and mixing processes in addition to pressure increasing reaction rates. In this work, a novel scaling approach is explored. In this approach, both the Reynolds and Grashof numbers are kept constant so that the effect of gravity is the same at all pressures. We report both numerical and experimental data proving that this approach guarantees the same non dimensional flow fields over a broad range of pressures.