GB819065A - Improvements in or relating to combustion equipment for example of gas turbine engines - Google Patents

Abstract

819,065. Generating combustion products under pressure. ROLLS-ROYCE Ltd. Nov. 16, 1956 [Nov. 16, 1955], No. 32876/55. Class 51 (1). In combustion equipment comprising an outer easing and an inner flame tube, for example for use in gas turbine engines in which large openings are provided in the flame tube for admission of dilution air which is mixed with the combustion gases to cool them, baffles are provided in association with the dilution air admission holes, the baffles being spaced from the wall of the flame tube towards the centre-line of the combustion space therein and lying across the paths of the dilution air flowing through the dilution air openings. The combustion equipment shown is of the annular kind comprising an annular flame tube formed by outer and inner annular walls 10a, 10b enclosed within an air casing formed by outer and inner annular walls 11a, 11b, the upstream end of the flame tube being substantially closed by structure 14 in which fuel injectors 15 are mounted. Primary air is admitted to the combustion zone through inlet 18 as disclosed in Specifications 744,593, 744,657 and 744,659. Large openings 19 are provided towards the downstream end of the flame tube for admission of dilution air. A supporting plate member 22 is mounted in the dilution air hole 19, a baffle plate 21 being secured to the radially inner end of the plate 22. Dilution air flowing through the opening 19 flows on either side of the plate 22 and impinges on the baffle 21 whereby mixing of the dilution air with the combustion gases is improved. In a second embodiment, the baffle supporting member comprises a pair of plates which are bowed outwardly along the central portions thereof so as to form a tubular air passage through the member, the baffle plate having a corresponding opening. In this arrangement, dilution air flows both through and over the outer surfaces of the baffle supporting members. In another arrangement, the baffle is of annular form being supported by a plurality of support members.