Patent GB-983191-A (GB)
Title: Improvements in fluid flow control valves
Inventor: GARDINER TERENCE EDWARD GOUVEN
IPC: F02C7/042
Filed: 1960-05-13
Abstract: 983,191. Gas turbine plant. BRISTOL SIDDELEY ENGINES Ltd. May 15, 1961 [May 13, 1960], No. 17036/60. Heading F1G. [Also in Divisions B7 and F2] Arrangement of air intake duct of aircraft jet propulsion plant. The air intake portion of a triple-unit powerplant is composed of three parts arranged side-by-side, each part having a forwardsection bounded by the lower surface 11, Fig. 1 of an aircraft wing, a lower wall 14 and four vertical walls. Each unit of the power plant comprises a gas turbine jet engine as described in Specification 985,192. An air duct 18 extends from the inlet to air intake opening 19, the duct being bounded by the vertical and lower walls, an upper partition 20 and an adjustable wedge structure 21, the space 22 between the latter two and the wing surface forming a boundary-layer air-duct 22 extending to an intake opening 23. The structure 21 consists of two parts 65, 66 connected by a hinge 67 to form a base which at its leading portion is hinged to a ramp 69 from which it extends forwardly to its leading edge 24 where it is supported by bearings carried by the vertical walls. At its downstream part the ramp 69 is hinged to another ramp 72 of a diffuser part of the duct 18; the downstream end of ramp 72 is supported by a pair of links 74 for altering the base parts 65, 66 preparatory to subsonic flight. For the same purpose the leading edge 89 of the wall 14 is hinged, the three edges 89 and associated structures 21 being adjustable in unison in dependence upon Mach number by servomotors and through cranks 91, 81. The ramp 69 has an inflexion 94 so that at cruising speed shock waves 95, 96 extend from the leading edge 24 and the inflextion 94 to the leading edge 89 of the wall 14, a further shock wave extending from the latter to the hinge 71 between the ramps 69, 72. The power plant is preferably operated with the normal shock wave downstream of the apex of the wedge structure as shown by the dotted line 98; a valve 99 is provided in the wall 14 to maintain this condition by 'blowing-off' excess air from the duct 18. Valve construction. The valve 99 is made up of a number of identical members comprising spaced upper and lower top-plates 100, 101, with aerofoil-shaped inner-surfaces joined by a lattice web 102, the valve controlling an opening 120 in the wall 14 and being of the same thickness as the latter. The valve may be tilted in either direction from the closed position wherein sealing is effected by providing one or both of the edges of each member with a flexible part; in the open position the upper and lower plates of adjacent members are in contact. The members are coupled by levers 103 secured to trunnions and by connecting rods 104, the foremost member embodying a pair of actuating levers 105 coupled by rods 106 and cranks 107 to a shaft 108 driven by a servomotor responsive to the difference in pressure between air in the duct 18 and the atmosphere during ground running and take off. Subsequently the valve is controlled by a device sensing movement of the shock wave, which device may also control the leading edge 89. The valve may be arranged in a curved duct, the valve being divided over the cross section by spacers, a separate set of members being disposed in each gap between the spacers. The wall 14 and the valve members may progressively increase in thickness.