GB736029A - Cooling system for gas turbine blading - Google Patents

Abstract

736,029. Gas turbine plant. LAGELBAUER, E. Dec. 5, 1952, No. 30970/52. Class 110 (3). A gas turbine plant comprising a high-pressure turbine driving directly separate high-pressure and low-pressure compressors in which the high-pressure compressor discharges through a combustion chamber to nozzles subtending over a segment of the blades of the highpressure turbine, has compressed air taken from the low-pressure compressor led to the remaining segment of the high-pressure turbine blades and the mixture of combustion gases and cooling air from the high-pressure turbine exhaust led to a lowpressure turbine. The high-pressure turbine 10 drives a low-pressure compressor 11 and a highpressure compressor 12 between which is arranged an intercooler 13. The air leaving the high-pressure compressor 12 is heated in a heat exchanger 15 by the exhaust gases and then further heated in a combustion chamber 16. The combustion gases from the chamber 16 pass through a nozzle 18 on to a segment 34 of the turbine blades 19. The exhaust gases from the turbine 10 pass to a low-pressure turbine 20 driving a load 21. Some of the exhaust gases may pass through a control valve 26 to a turbine 23 driving another low-pressure compressor 24. The turbine 23 may be omitted and the compressor 24 driven by the turbine 20. The control valve 26 may, in an emergency, divert the gases direct to atmosphere through conduit 27. The air from the the low-pressure compressors 11, 24 is divided by a control valve 28, part of this air passes through the intercooler 13 to the high-pressure compressor and part passes through the conduit 65 to the segment 31, Fig. 3, of the turbine blades. The compressed cooling air is mixed with the combustion gases and passes therewith through the duct 63 to the lowpressure turbine 20. The compressed cooling air passes over the blades 19 in a radial direction. In a modification, the cooling air passes over the blades in an axial direction. In this arrangement, an axial flow compressor stage is mounted on the compressor shaft so that it discharges through fixed vanes on to the turbine blades.