Direct numerical simulation of premixed turbulent flames

The enormous increase in computer power during the recent past has made it possible for the first time to carry out direct numerical simulation (DNS) of turbulent reacting flow fields, without the use of a turbulence model. This has opened up a significant new area of research into the fundamental processes of flame-turbulence interaction since it is now possible to solve the governing equations in full detail, resolving even the smallest of the important features of the flow and the flame. In many ways, the technology of DNS remains in its infancy, and the present work seeks to extend current methods in order to take advantage of massively parallel supercomputers. The governing equations are presented and necessary simplifications are justified in the light of current computational capabilities. A numerical discretization scheme suitable for parallel implementation is described, and results are presented for a series of simulations of simple test problems. The relevance of the results is discussed in the light of current turbulent-combustion modelling, and suggestions are made for future work.