GB838602A - Improvements in or relating to gas turbine plant - Google Patents

Abstract

838,602. Gas-turbine plant; axial-flow compressors. POWER JETS (RESEARCH & DEVELOPMENT) Ltd. Feb. 27, 1958 [March 6, 1957], No. 7384/57. Classes 110 (1) and 110 (3). A gas-turbine plant comprising two rows of axial-flow rotor blades designed for contrarotation and arranged in direct guide blade relationship with one another and two further rows of axial-flow compressor rotor blades arranged in series flow relationship with one another, the tip diameters of which are greater than those of the first-mentioned rows and each of which is in driving connection with a separate one of the first-mentioned rows to rotate therewith in the same sense and at the same rotational speed, has a row of axialflow compressor blades interposed in seriesflow relationship between the two compressor rotor rows. The ducted fan gas-turbine jetpropulsion engine shown comprises an axialflow compressor 1, 2, supplying combustion air to an annular combustion chamber 13 feeding combustion gas to rotor blades 18 driving the compressor 1, 2. The exhaust gases from the blades 18 enter the contra-rotating rows of blades 27, 28 arranged in series-flow relationship with one another. The shrouds 29, 30 of these rows of blades carry rows of axial flow ducted fan blades 31, 32 which are separated by a row of axial-flow stator blades 37. The turbine rotor blades 18 may be designed for zero swirl at outlet in which case the blades 27 may rotate in the same direction as the blades 18. The blades 27, 28 however must contra-rotate and must be in direct guide blade relationship with one another. In a modification, the rows of blades 27, 28 are each replaced by two rows of blades connected to each other. In another modification, Fig. 5 (not shown), air is supplied to a combustion chamber by a compressor formed by rows of blades mounted on the shroud rims of turbine blades. The compressor blades, but not the turbine blades, are separated by rows of stator blades. The application of the invention to a by-pass engine is also described. The by-pass compressor is formed of two contra-rotating rows of blades separated by a row of stator blades. The compressor blades are driven by two rows of turbine blades in direct guideblade relationship with one another. In a further modification, the compressor is formed in two stages one of which is mounted on the tips of the blades of the other. The blades of the inner row are arranged in direct guideblade relationship whereas the blades of the outer row are separated by rows of stator blades. Specifications 586,435 and 594,522 are referred to. Specifications 588,092 and 592,615 are also referred to in the Provisional Specification.