Large-eddy simulation of realistic gas turbine combustors

Large-eddy simulation is a promising technique for accurate prediction of reacting multiphase flows in practical gas-turbine combustion chambers involving complex physical phenomena of turbulent mixing and combustion dynamics. Development of advanced models for liquid fuel atomization, droplet evaporation, droplet deformation and drag, and turbulent combustion is discussed specifically for gas-turbine applications. The nondissipative, yet robust numerical scheme for arbitrary shaped unstructured grids developed by Mahesh et al. (Mahesh, K., Constantinescu, G., and Moin, P, "A New Time-Accurate Finite-Volume Fractional-Step Algorithm for Prediction of Turbulent Flows on Unstructured Hybrid Meshes," Journal of Computational Physics, Vol. 197, No. 1, 2004, pp. 215-240) is modified to account for density variations due to chemical reactions. A systematic validation and verification study of the individual spray models and the numerical scheme is performed in canonical and complex combustor geometries. Finally, a multiscale, multiphysics, turbulent reacting (low simulation in a real gas-turbine combustor is performed to assess the predictive capability of the solver.