The procedure uses a liquid fuel and an oxidant containing between 20 and 100 per cent oxygen delivered through an injector (2) inside an aperture (1). The coefficient of combustion is maintained during the whole period of combustion at a level determined from a formula based on the distance of the injector from the end of the aperture, the velocity of fuel droplets from atomisers and the relative percentage volumes of fuel and oxygen at the aperture's outlet.
