Abstract: Liquid fuel is evaporated and mixed with an oxidizing agent in a mixing chamber of a reformer by first introducing substantially only the liquid fuel in an axial downstream direction into a first upstream zone of the mixing chamber via a nozzle so as to atomize the liquid fuel. Then steam is separately introduced into the upstream zone and contacted with the atomized fuel to cause the fuel to evaporate. An oxidizing agent is then introduced downstream of the first zone in a second zone of the mixing chamber to the evaporated fuel and uniformly mixing the oxidizing agent with the evaporated fuel.

Abstract: The invention relates to a reformer mixing chamber comprising a feed for liquid fuel supply by means of a nozzle, a feed for a water vapour supply to the first area of the mixing chamber and a feed for oxidising agent supply to the second area thereof, wherein said second area is arranged downstream of the first area. Said invention also relates to a method for operating the mixing chamber consisting in evaporating a fuel and in mixing said fuel with an oxydation agent. The liquid, preferably cold, fuel is introduced into the mixing chamber by means of a nozzle and is atomised. The contact between the atomised fuel and hot water vapour also introduced into the mixing chamber initiates the fuel vaporisation in the first area thereof. The oxidation agent, preferably also cold, is added to the evaporated fuel in the second area of the mixing chamber and is homogeneously mixed therewith.