Injection element for a combustion reactor, more particularly, a steam generator

An injection element for a combustion reactor in which hydrogen and oxygen are mixed and reacted prior to being fed in a stoichiometric ratio to a main combustion chamber, comprising

• an inlet for the hydrogen,
• an inlet for the oxygen,
• a mixing chamber for the hydrogen and oxygen,
• ignition means for igniting a hydrogen-rich mixture of hydrogen and oxygen,
• an ignition chamber into which the hydrogen inlet opens and which has a flow cross-section that widens in the direction of the flow from said hydrogen inlet toward said mixing chamber, the ignition chamber having an outlet with a cross-section smaller than the flow cross-section of the ignition chamber, the outlet of the ignition chamber and the oxygen inlet both opening into the mixing chamber, and
• an ignition oxygen inlet opening into the ignition chamber,
• the ignition means being disposed in the ignition chamber immediately upstream of its outlet, and
• said oxygen inlet comprising a conduit extending coaxially through the ignition chamber to said mixing chamber.