Abstract: A fuel system particularly for a gas turbine engine in which a tubular shaft rotatable during operation of the engine at engine speed or at a speed proportional thereto has a fuel inlet through which liquid fuel is introduced into the interior of the shaft, the peripheral wall of the shaft having at least one port therein communicating externally of the shaft with a combustion region of the engine and comprising a first resiliently-supported valve member mounted on the outside of the peripheral wall of the shaft in registration with the port to move away from the shaft centrifugally as the speed of rotation of the shaft increases, thereby to open the port and thus to allow fuel to flow through the port to the combustion region.

Abstract: An engine having a first reaction chamber to which fuel is to be supplied, either alone or with another reactant, and to which heat is applied to effect an endothermic chemical reaction to produce, under substantially reversible conditions, a reformed fuel, a second reaction chamber to which the reformed fuel discharged from the first reaction chamber is passed together with air or other reactant to effect an exothermic chemical reaction in the second reaction chamber, and a heat exchanger (conveniently of the fluidized bed type) to transfer heat produced by the exothermic reaction in the second reaction chamber to the first reaction chamber to effect the endothermic reaction.