Similarity parameters in two-phase combustion.

Scaling is an important issue in many practical applications. While some sc aling laws are already applied in combustion, none of them addresses the ph enomena involving the liquid phase (e.g. in a liquid-fueled burner). The go al of this paper is to study systematically those phenomena and to establis h scaling laws that rake the liquid phase into account. A dimensional analy sis is performed, leading to the expression of four dimensionless groups. T he first one describes the combustion mode and the global aspect of the fla me. The next two address the stabilisation of the flame and the last one is related to the atomiser efficiency. In the second part of the paper, those dimensionless groups are applied to practical devices. The flexibility of this analysis is demonstrated using different kinds of injectors and fuels. In each case, the four dimensionless groups correctly predict some physica l characteristics of the flame such as its mode of stabilisation, lift-off etc. Finally another practical application is studied: the design of a smal l scale burner using the proposed scaling laws. (C) Elsevier, Paris.