GB723010A - Improvements in or relating to combustion apparatus - Google Patents

Abstract

723,010. Generating combustion products under pressure. POWER JETS (RESEARCH & DEVELOPMENT), Ltd. Dec. 30, 1952, [Jan. 2, 1952.] No. 196/52. Class 51 (1). A combustion chamber having an air inlet in the region of which large drops of fuel are introduced, a flame stabilizer and ignitor spaced downstream from the inlet and an atomizing liquid fuel injector which injects fuel into the chamber on the downstream side of the flame stabilizer, is formed with a diffusing duct through which the air stream flows from the inlet to the flame stabilizer. The annular combustion chamber shown comprises an air casing formed by two tubular walls 11, 12 enclosing an annular flame tube formed by two co-axial tubular walls 13, 14. The flame tube and the air casing each comprise an upstream diffuser passage followed by a parallel section. The divergence of the portions 11b, 11c, 12b, 12c of the air casing is greater than the divergence of the corresponding sections 13b, 13c, 14b, 14c of the flame tube so that there is a small amount of diffusion in the passage between the walls. To maintain an equal distribution of air around the flame tube, the radial spacing of the inner walls of the casing and flame tube is greater than that of the outer walls. The apertures 20 are longer than the apertures 19 to compensate for their reduced width arising from the smaller circumference of the inner wall. A fuel manifold 27 is mounted between cylindrical walls 13a, 14a of the flame tube. Fuel is supplied in this manifold at a small excess pressure so that the fuel enters the air stream in the form of comparatively large drops which are atomized by the velocity of the airstream. The fuel is ignited by a plug 35 mounted on the downstream side of a flame stabilizer baffle 30. The baffle 30 consists of an annular channel facing downstream with a large number of fingers 31a, 31b which extend to the walls of the flame tube where they are joined together 32a, 32b. A number of fuel injectors 33 of the atomizing type are located within the gutter. These injectors form pilot flames which are used for igniting the chamber under starting and idling conditions, but are used continuously. In another embodiment the flame stabilizer 30 is formed as a gutter of triangular cross section with the outside rearward edges turned in so that the width of the open end is less than the maximum width of the gutter. The atomizing fuel injectors in this case face upstream. The flame tube is supported from the outer casing by a ring of channel-shaped brackets 15, 16 and by strips of metal 17, 18. Reference has been directed by the Comptroller to Specification 690,941.