1. Combustion definitions and mechanisms

1.1 Definitions

Combustion covers all the chemical reactions that take place during the complete or partial oxidation of a fuel by an oxidizer. These oxidation-reduction reactions are generally exothermic. The oxidized body, which loses one or more electrons, is the fuel, and the reduced body, which gains one or more electrons, is the oxidizer.

In practice, a fuel (the name used for heat production operations, in furnaces or boilers) or a combustible (the name used for use in engines) is a natural or manufactured gas, liquid or solid containing the elements oxidized during the reaction and, possibly, other elements not directly involved in the reaction. The latter elements are found in smoke and/or ash, which respectively contain the gaseous products and the...