GB1153034A - Combustion Apparatus - Google Patents

Abstract

1,153,034. Gas turbine &c. combustion apparatus. ROLLS-ROYCE Ltd. Dec.20, 1966 [Sept.21, 1965], No.40221/65. Heading F1L. A duct 12 contains a V-cross section flame stabilizing gutter 11, wherein the downstream edge 18 of each limb of the V has small projections 19 and each arm 16 of the gutter extends from a centre part 15 in a downstream direction obliquely to the general direction of airflow 20. The duct 12 may be a rectangular ram jet duct or the annular by-pass duct of a gas turbine engine, in the latter case the gutter 11 being curved to follow the curvature of the duct. A pipe 25 on centre part 15 supplies fuel to branch pipes 28 each extending along the full length of an arm 16 on the downstream side thereof and communicating through holes 29 with the upstream side. Thus, fuel leaving the holes 29 is driven by the airflow 20 to the edges 18 of the arm where part is drawn into vortices 23 set up by the arm and the remainder is drawn into the wake 21. Igniters 24 on the centre part 15 ignite the adjacent combustible mixture to form a pilot flame which is drawn by the spiral motion of the vortices 23 outwards along the arms to ignite the fuel supplied through the holes 29 remote from the part 15. The projections 19 have the effect of causing burning gas from the vortices to be drawn into the wake 21, as shown at 27. The end 17 of each arm 16 is substantially parallel to the adjacent duct wall 14 so that the flame is not directed against the wall, and is formed such that the limbs of the V are inclined at a greater angle, Fig. 4 (not shown), than at part 15. If the mixture in the pilot zone adjacent part 15 is made sufficiently fuel-rich, fuelling along the length of the arms 16 may be dispensed with. Fuel may alternatively or additionally be injected into the wake 21 from injectors 30 mounted on the duct sidewalls 13, or, in a further modification, may be injected upstream of the gutter.