Abstract: A unique, small microturbine engine adapted to integrate with an electrical generator for producing electrical power has been developed. The microturbine includes an ejector cooling scheme, a prevaporizing combustor, and a combustor air bypass. The ejector cooling scheme uses energy in the hot exhaust gas stream of the microturbine to entrain a flow of ambient air that cools the generator. The prevaporizing combustor of the present invention allows liquid fuel to be vaporized in a small amount of air prior to combustion, thereby increasing combustion efficiency and decreasing combustor size requirements. The combustor air bypass allows a fraction of the compressor discharge air to bypass the prevaporizing combustor under certain operating conditions. This permits control of the overall equivalence ratio and the fuel/air mixing process in the combustion zone, improving efficiency and operability.

Abstract: A premixing injector for use in gas turbine engines assists in the lean premixed injection of a gaseous fuel/air mixture into the combustor of a gas turbine. The premixing injector is designed to mix fuel and air at high velocities to eliminate the occurrence of flashback of the combustion flame from the reaction zone into the premixing injector. The premixing injector includes choked gas ports, which allow the fuel supply to be decoupled from any type of combustion instability which may arise in the combustor of the gas turbine and internal passages to provide regenerative cooling to the device.