METHODS FOR EXAMINING ANISOTROPIES IN EARLY COMBUSTION .2. THEORETICAL DEVELOPMENTS

This study reports some preliminary steps in the development of techni ques for simplifying the problem of analysing spatially propagating re actions in anisotropic multi-phase systems. The target situation is co mbustion in a spark ignition petrol engine; nevertheless the method de scribed has a much broader range of application. Both present and futu re experimental techniques and C.A.D. methods concerned with spatially resolved combustion data are and will be faced with enormous complexi ty of detail. This is essentially due to the geometry and dimensionali ty of the problem of the propagation of in-cylinder combustion. Howeve r, many features of interest concern the fundamental structural proper ties of the burning air/fuel system, such as how far combustion has pr ogressed, how a given burning region is linked to others, how robust a re these connections with respect to flow field disturbance. These are the type of issues the formalism is best suited to address. The appro ach is mainly analytical and the combustion description is treated via a set of mathematically tractable special cases of increasing complex ity. From these a general computational approach is proposed for real situations. The background of this work is the recent introduction of a percolation description of combustion.