GB919826A - Improvements relating to combustion units - Google Patents

Abstract

919,826. Generating combustion products under pressure; liquid fuel furnaces. GARRETT CORPORATION. March 18, 1959 [March 18, 1958], No. 9350/59. Class 51(1) and 51 (2). A combustion unit comprises a flame tube within an outer casing and separated from it by an annular air supply space, an air inlet extending tangentially into the annular space through the wall of the casing at one end, a liquid fuel nozzle situated adjacent that end, one or more inlets for admitting primary air in a rotary manner from the annular space into the flame tube adjacent the fuel nozzle and a number of longitudinal baffles distributed around the flue tube within the annular air supply space arranged to direct a supply of air from the region of the tangential inlet in an axial direction towards secondary air inlets arranged downstream of the fuel nozzle. The combustion unit, Figs. 1, 2, comprises an outer casing 9 surrounding a flame tube 32 to form an annular air passage 40. The casing 9 comprises a cap 10, with a tangential air inlet 14, which is attached to a skirt 11 by a clamp 22. A fuel supply nozzle 13, which holds a swirl vane guide 24 against the end of the cap 10, extends through an opening 30 in the flame tube end cover 28. The swirl guide 24 comprises a flat disc provided with spiral vanes 26, the edges of which are fused to the cover 28. The flame tubes have three rows of spaced openings 33, 34, 35. Flow straightening vanes 37 are welded to the flame tube between the openings 33. In operation, part of the air supplied by the passage 14 passes through the swirl vanes 26 and opening 30 to create a vortex in the flame tube and mix with the fuel from: the nozzle 13. The remainder of the air flows through the annular passage 40 and straightening fins 37 to the openings 33, 34, 35. Due to the vortex part of the air flowing through the openings 33 will flow upstream and traverse the fuel spray from the nozzle 13.