| 摘要 |
<p>709,002. Centrifugal pumps; gas turbine plant. ROLLS-ROYCE, Ltd. May 8, 1951 [May 12, 1950]. No. 11973/50. Classes 110(1) and 110(3) [Also in Groups XI and XXVII] A fuel system for a gas turbine engine comprises a low-pressure fuelmetering device delivering fuel to the eye of the impeller of a centrifugal pump, and flow-restricting means connected with the delivery of the pump and having such flow characteristics that the maximum delivery is obtained with a radial depth of fuel in the impeller less than the radius of the impeller. A booster pump 20 supplies fuel from a tank 16 to a main pump 25 through, a nozzle 31 which directs the fuel against the surface of the impeller 25a within a central clear space 27. Pump 25 delivers the fuel to the fuel injection nozzles 19 of a gas turbine engine, and is driven through gearing from the engine shaft or by an electric motor or an air turbine. The rate of flow is controlled by a throttle 22, the inlet pressure of which is kept constant by a relief valve 23 which returns fuel to the tank 16 by way of a pipe 24. The pressure within the space 27 is kept substantially constant by venting the space to atmosphere through a pipe 33. Pump 20 and valve 23 may be eliminated, the pressure within the tank 16 being kept constant by supplying air under pressure to the top of the tank 16. The air is supplied by a blower, a blow-off valve keeping the pressure constant. Alternatively pump 20. valve 23 and throttle 22 may be replaced by a variabledisplacement pump of the kind in which the rotor carries radially disposed pistons which are reciprocated by engagement with the inner wall of a casing the eccentricity of which in relation to the rotor is controlled by a lever replacing Specification, the pump 25 may have more than the throttle lever. According to the Provisional one volute.</p> |
