GB841110A - Improvements in or relating to jet propulsion nozzle arrangements - Google Patents

Abstract

841,110. Braking jet-propelled aircraft. ROLLS-ROYCE Ltd. March 11, 1958 [March 13, 1957], No. 8359/57. Class 4. [Also in Group XXVI] In a jet propulsion nozzle arrangement for aircraft wherein the nozzle is divided into a plurality of circumferentially-spaced longitudinal channels for noise suppression, peripheral outlets to atmosphere are provided in the nozzle wall and the rear end of the nozzle carries a plurality of hinged deflectors which may be moved to block the rearward flow of propulsive gases and deflect them forwardly through said peripheral outlets. In the embodiment shown wherein Fig. 2 is an end view in direction 2, Fig. 1 and Fig. 1 is a section on line 1-1, Fig. 2 the nozzle comprises an outer wall 112 and an inner wall 110 forming a bypass duct 113 therebetween, the wall 110 forming also the outer wall of the exhaust-gas passage 111. The nozzle also comprises a plurality of equi-angularly spaced hollow structures 114 each extending radially inwards from the outer wall 112 through wall 110 to a central support tube 115, each structure comprising spaced walls 114a bridged by a plurality of guide vanes 117, each pair of walls 114a diverging rearwardly from a common edge 114b so that they form a plurality of rearwardlyconverging sector-section passages for the gas from passage 111 and by-pass air from duct 113. The wall 112 which is cut away at 116 to place the interior of each structure 114 in communication with atmosphere is extended rearwardly by a cylindrical portion 18 and radial spindles 21, each carrying a sector shaped shutter 19, are pivoted in portion 18 and tube 115 for simultaneous operation by power means (not shown) from positions parallel to the nozzle axis as shown in the upper half of the figures to transverse positions. In the former position the flow from the jet nozzle is unimpeded, but in the latter position shutters 19 block rearward flow and force the propulsive jet to flow outwardly and forwardly through structures 114 and out of apertures 116. A variety of other deflectors are described for causing the deflection of the gases ; in one sector shaped shutters pivot about axes which are tangential to the circumference of the nozzle extension and move from positions outside the gas flow to transverse positions. Alternatively the same form of shutter may be extended forwardly to cover the cutouts 116 when inoperative. Clam-shell and petal type deflectors also are described and air-intake openings may be arranged forward of apertures 116 to enable cooling air to flow through structures 114 when the nozzle is operating normally. In one embodiment means is described for locking the deflectors in their operative positions. Specification 768,553 is referred to.