GB1435349A - Combustion heads - Google Patents

Abstract

1435349 Combustion heads INSTITUT FRANCAIS DU PETROLE 6 Sept 1973 [8 Sept 1972] 41998/73 Heading F4T A combustion head comprises an elongate hollow body 1 connectable to a first end to a comburent source and at a second end to a combustion chamber 3, a rigid fuel supply conduit 5 coaxially in body 1 and terminating in a fuel discharge jet (11), Fig. 5 (not shown), comburent rotating means 16 fixed around jet (11) and means for producing relative displacement between at least a portion of body 1 adjacent the second end thereof and the assembly of jet (11) and rotator 16 between a first position in which rotator 16 is operable to rotate substantially all the comburant flow through body 1 and a second position in which said assembly is in a downstream position relative to said portion of body 1 so as to rotate part only of the comburant flow. In one form, Fig. 2, (not shown), Fig. 3 in the first position swirl blades 16 are located in a cylindrical discharge part of body and conduit 5 is adjusted to project jet (11) and blades 16 out of body 1 and into the combustion chamber in said second position. Alternatively, conduit 5, jet (11) and blades 16 may be fixed relative to body 1 and the outlet portion (1b), Fig. 4 (not shown), of body 1 houses a sleeve (23) slidable from the first position, in which blades 16 are in a cylindrical part of sleeve (23) to the second position in which blades 16 are downstream from a frusto-conical outlet part of sleeve (23). To maintain a constant comburant flow rate as the combustion head is adjusted between the first and second positions, during which the comburent pressure drop in body 1 due to the assembly of jet (11) and blades 16 decreases means may be provided for automatically compensating for this decrease by adjustment of an obstruction in body 1. This means may comprise a diaphragm with an adjustable aperture, or a frusto-conical bore portion (2<SP>1</SP>), Fig. 10 (not shown), and an obstructing member (37) on conduit 5, member (37) and portion (2<SP>1</SP>) being relatively movable. A honeycomb device 7 ensures a substantially uniform comburant flow velocity parallel to the axis of body 1 throughout its cross-section upstream of blades 1. The fuel may be gas or oil atomized by jet 11 which terminates in a hemispherical or frusto-conical part (11a), Fig. 5, surrounded by a similarly shaped part (12a) extending from a cylindrical sleeve 12, the swirl blades being mounted on part 12a, and a small amount of comburent flowing through an annular gap (13) between sleeve 12 and jet (11). Alternatively liquid fuel may be supplied to jet (11) and gaseous fuel to the annular gap (13).