GB860314A - Improvements in gas impingement starters for gas turbine engines - Google Patents

Abstract

860,314. Gas-turbine plant. GENERAL ELECTRIC CO. Dec. 19, 1958 [Jan. 2, 1958], No. 41042/58. Class 110 (3). A gas starter for a gas-turbine engine having a plurality of stator blades 22 for directing the working fluid against the rotor blades 40, comprises blade extensions 58 which are formed with substantially the same aerofoil contours as the blades 22 and which with inclined walls 46, 52 provide a passage through an opening 18 in the engine casing 1 for turning the starting gas tangentially with respect to the aerofoil contours, Fig. 3, and at the same time radially and axially with respect to the rotor axis, the passage being situated radially outwardly from the working fluid passage of the gas-turbine engine. A pair of circumferentially elongated housings 2 are located on opposite sides of the turbine casing 1, each housing having an opening 5 to admit. the compressed gas in a direction opposite to that of the turbine rotation. Two circumferential slots, 18 in the rotor casing and 44 in the shroud 26 are provided and extensions of the stator blades extend radially outwards into these slots. Passageways connecting the interior of housing 2 with the turbine blades are formed by the walls 46, 52 and wall 46 projects forwardly from the edge of slot 18 into the housing, the shoot so formed has side walls 50 and is divided up by the stator blade extensions. The walls 46, 52 give the starting gas a radial and an axial component of velocity while the contours 62, 64 of the stator blade extensions 58 deflect the gas tangentially on to the turbine blades 40. In another embodiment stub blades are mounted on the wall 16 of the housing-extending radially inwards and although separate from the stator blades form in effect extensions thereof.