GB737082A - Improvements in free-piston compressors or gas generators - Google Patents

Abstract

737,082. Elastic fluid turbines. PERROTT, F. C. May 16, 1952 [Feb. 16, 1951], No. 3796/51. Class 110 (3). [Also in Group XXVII] - Gas turbines are supplied by a free piston compressor or gas generator (see also Group XXVII). Air and/or combustion products is or are discharged from the cylinder or cylinders at the end of the compression and/or the start of the working stroke. In Fig. 2 inlet ports 42 are supplied with scavenging air and the exhaust is discharged at 44. During or immediately prior to the injection of fuel, valves 46 are opened and air is discharged. The apparatus is mainly to deliver compressed air although combustion products may also be mixed with the air. Fig. 1 shows a plant in which a gas generator 12 is supplied with air under pressure by an axial flow rotary compressor 10. The exhaust of the generator drives low pressure turbines 14, 16 and the generator also supplies air and/or combustion products through a conduit 15a to an highpressure turbine 19. The turbine 19 may exhaust into the conduit 13 or as shown by the chain dotted line may deliver into the conduct 11. Intercoolers 25, 26 may be provided. A combustion chamber 27 may be inserted between the gas generator and the turbine 19. The inlet ports 41 may be arranged to impart a tangential movement to the air. The compressor 10 may be replaced by a reciprocating compressor driven by the reciprocating movement of the pistons of the gas generator. There may be several generators as in Fig. 2 coupled through a swash plate. There is a tendency for a port 45 to be closed by the pistons as they come together and this prevents the pistons coming into contact. Compressed air may be supplied for a combined steam and gas turbine plant. The time of opening of the valve 46 may be adjusted so that it takes place either shortly before or shortly after the instant when the pressure in the cylinder becomes equal to that beyond the valve. Adjustment may be accomplished preferably automatically in accordance with the delivery pressure in the duct 15a. Adjustment may be effected, for example, either by a pressure controlled throttle valve in the duct 15a or by regulating the amount of fuel injected into the cylinder in accordance with the pressure in the duct 15a. The valve 46 may be formed or arranged to provide a throttling effect. The throttling may be provided by the duct through which the air or combustion products are discharged. Means may be provided for adjusting the point in the stroke at which fuel injection commences.