Abstract:     The vital role of simulations and computational insights in reducing pollutant emissions, designing better engines and better fuels, and assessing the technical and economic viability of radically different combustion technologies, is now clearly established. A key enabling step is the development of computational approaches that allow our increasingly detailed knowledge of the chemical kinetics of realistic fuel oxidation to be applied to the modeling and simulation of combustion reactors. In this talk, I will briefly review the challenges associated with the integration of detailed chemical kinetics in reactive flow simulations. I will then discuss the progress we have made in the analysis and reduction of complex kinetic networks, with a focus on graph-based techniques and the characteristics of the stand-alone reduced models they typically generate. Using Large-Eddy Simulations of turbulent flames as case study, I will show how these techniques are enhanced through careful integration and coupling with CFD tools, wherein the flow characteristics adaptively inform the reduced chemical model to be used. I will conclude on the remaining challenges still to overcome, and potential avenues to do so.

Biography:   Dr. Pepiot has a Ph.D. and M.S. in Mechanical Engineering from Stanford University, and a M.S. in Aeronautics and Astronautics from the Ecole Nationale Superieure de l'Aeronautique et de l'Espace (Supaero) in Toulouse, France. Prior to joining the Cornell faculty in 2011, Dr. Pepiot was a research scientist at the National Renewable Energy Laboratory in Golden, Colorado, leading the Biomass Gasification Process Modeling and Optimization Task. Dr. Pepiot’s main interest is in developing new modeling and computational tools to improve the description of complex chemical processes in CFD simulations of energy systems, especially in combustion. Her current work includes the development of automatic chemical kinetic analysis and reduction tools for multi-component fuel mixtures, new algorithms to efficiently handle complex chemistry in large eddy simulation of turbulent flames, with a focus on particle PDF methods, and the use of detailed multi-scale numerical techniques to simulate reactive particle-laden flows with application to biomass thermal conversion and chemical looping combustion. She is the recipient of the 2013 James M. and Marsh D. McCormick Excellence in Advising Award and of the 2014 John Swanson ’61 ME in honor of his mother, Dorothy G. Swanson Excellence in Teaching Award.