Toward Validation of Large Eddy Simulation for Turbulent Combustion

A quantitative overview focused on validation of the large eddy simulation (LES) technique for application to gas-turbine combustion processes is provided. The primary objective is to provide a systematic analysis of the current state of the art and assist in the development of technical performance metrics for model validation. Research is currently required to provide both improved multiphase combustion models and improved datasets for validation. Phenomenological requirements for further model development must be established through more detailed analyses of the space-time characteristics of small-scale turbulence-chemistry interactions. Concurrently, a refined set of implementation requirements must be established for LES, and a systematic hierarchy of databases for model validation must be developed. Steps taken toward these goals are described by focusing on validation requirements, boundary conditions, and the progressive implementation of LES in more complex configurations. First the distinct set of tradeoffs and requirments for LES are listed. A systematic progression of case studies that highlight key aspects related to the state of the art is then presented. In conclusion, recent findings associated with the International Workshop on Measurement and Computation of Turbulent Nonpremixed Flames, from the perspective of validation and model development for LES, are highlighted.