GB995182A - Improvements in or relating to gas turbine engine combustion equipment - Google Patents

Abstract

995,182. Gas turbine combustion chambers; gas turbine blades. ROLLS-ROYCE Ltd. March 5, 1964 [June 20, 1963], No. 24673/63. Headings F1G, F1L and FIT. A gas turbine engine combustion chamber comprises an outer casing, a flame tube mounted within the outer casing and spaced therefrom, a dilution air duct extending axially alongside the flame tube, an axially extending primary combustion air duct leading to the upstream end of the flame tube, and a plurality of angularly spaced nozzle guide vanes mounted within and extending radially completely across the flame tube, each guide vane having a passage therein communicating with the dilution air duct, and the wall of each guide vane having at least one aperture communicating with the passage and spaced from the downstream end of the flame tube such that dilution air passes through the apetures to mix with the combustion gases flowing through the flame tube. A gas turbine engine combustion chamber, Fig. 2, comprises an annular wall 21 surrounding an annular flame tube 26. A wall 25, formed as an extension of the outer wall of the flame tube 26, co-operates with wall 21 to form an annular dilution air duct 27 and with an inner wall 22 to form an annular primary air duct 28. A perforated wall 30 constitutes the upstream end of flame tube 26. Hollow turbine inlet guide vanes 31 extend substantially throughout the downstream half of the flame tube 26 integral with the walls thereof. Dilution air from duct 27 flows to the interior of guide vanes 31 and enters flame tube 26 through holes 34 in the vane walls. Holes may also be provided in the leading and trailing edges of vanes 31 together with a heat shield at the leading edge. In a modification, Fig. 7, a partition 40 extends upstream from the leading edge of each vane 31 to the flame tube wall 30 to divide the annular flame tube into a series of compartments 40a. Each partition 40 is hollow having a passage 40b for cooling air communicating with the primary air duct 28 and the vane passage 32. In a further modification, Fig. 9, the guide vanes have the dilution air holes on their low pressure surfaces only. The primary and dilution air ducts are supplied with compressed air through air shoots 38, 37, respectively, arranged alternately. The entrance to each dilution air shoot 37 includes the entrance 41 to a cooling air duct 42 adjacent the inner wall of flame tube 26. Additional cooling air inlets from ducts 37, 42 to the interior of the flame tube, including holes 45 intermediate adjacent guide vanes are provided. A fuel atomizing member 43 is mounted at the entrance of each primary air duct to the flame tube 26. A curved deflecting plate 44 downstream thereof causes primary air to circulate in the upstream half of the flame tube 26 and impinge on the atomizing member 43.