Application of CFD in combustor design technology

Multidimensional computational combustion dynamics has been used over the last twenty years to provide improved insight during gas turbine combustor design and development processes. The empirical/analytical combustor design methodology that was first demonstrated under the Army sponsored Combustor Design Criteria Validation program conducted during 1974-1978 has been used in the design and demonstration of 15 advanced rig combustors, four technology demonstrator engine combustors, three engine combustors, and one small turbine augmentor. Recognizing the limitations of turbulent combustion models, numerics, and the assumptions required to fully specify the boundary conditions for practical gas turbine combustion systems, a new technique that combines state-of-the-art turbulent combustion models with 'consistent' macro-volume expressions ('hybrid combustor modelling') was proposed. This hybrid modeling approach has been calibrated with combustors that include diffusion flame, lean premix/prevaporized, or rich-lean types of combustion processes. The hybrid modeling technique gives good 'quantitative' agreement with measured data on gaseous emissions, smoke, combustion efficiency, lean blowout fuel-air ratio, pattern factor, liner wall temperature levels, and gradients of a number of combustors.