Abstract: A downhole steam generation apparatus and method of use are provided. The apparatus may include an injection section, a combustion section, and an evaporation section. The injection section may include a housing, injector elements, and injector plate. The combustion section may include a liner having channels disposed therethrough. The evaporation section may include conduits in fluid communication with the channels and the combustion chamber, and a nozzle operable to inject a fluid from the channels to the combustion chamber in droplet form. A method of use may include supplying fuel, oxidant, and fluid to the apparatus; combusting fuel and oxidant in a chamber while flowing the fluid through a plurality of channels disposed through a liner, thereby heating the fluid and cooling the liner; and injecting droplets of the heated fluid into the chamber and evaporating the droplets by combustion of the fuel and the oxidant to produce steam.

Abstract: A method for producing hydrocarbons from a reservoir is provided. The method includes positioning a burner having a combustion chamber in a first well, supplying a fuel, an oxidant, and one of water or steam from the surface to the burner in the first well, supplying a viscosity-reducing gas from the surface to the reservoir in a conduit separate from the fuel, igniting the fuel and the oxidant in the combustion chamber to generate heat and steam in the burner, injecting the viscosity-reducing gas and steam into the reservoir to reduce the viscosity of and heat hydrocarbons within the reservoir, and recovering hydrocarbons from the reservoir.