GB645696A - Improvements relating to fuel-injection-means for gas-turbine-engines - Google Patents

Abstract

645,696. Liquid-fuel burners. ROLLSROYCE, Ltd. April 2, 1947, No. 9036. [Class 75(i)] A fuel-injection device for a gas turbine engine comprises two fuel atomizing orifices arranged coaxially and fed from separate swirl chambers into each of which fuel is injected through ports which impart a rotational swirl to the fuel within the chambers, the first of the chambers being formed by a central bore of full circular cross-section bounded by a wall of circular annular cross-section and terminating at one end in an aperture of full circular cross-section coaxial with the bore and forming the fuel atomizing orifice from the first swirl chamber, the second of the chambers being of circular annular cross-section having its inner defining wall in part formed by the annular wall and terminating in an aperture of circular cross-section coaxial with the chamber forming the fuel atomizing orifice from the second chamber, the arrangement being such that the hollow cone of atomized fuel issuing from the first swirl chamber lies within the hollow cone of atomized fuel issuing from the second swirl chamber. The device consists of a body 1 with main and idling fuel supply ducts 2 and 3, the duct 2 opening to an annular space 10 on one side of a disc 8 joined by passages 11 to an annular space 12 on the other side of disc 8 which opens to a number of passages 20 arranged in spiral or tangential form in a disc 19 and extending inwards to a central space 21 leading to a conical bore 23 which terminates in an atomizing orifice 24 from which the main fuel supply issues in the form of a conical jet 25. The idling fuel supplied through duct 3 passes to bore 6 formed in the body 1, central chamber 9 formed in disc 8, cylindrical chamber 14 provided with a helically grooved plug 17, conical swirl chamber 15 terminating in an orifice 16, which may be set back or may extend through the orifice 24 downstream of such main orifice 24. The fuel issues from orifice 16 in the form of a conical jet 18 lying within the conical jet 25 from the main orifice 24. The swirl plug 17 has a spring-pressed base piece 30 to retain it in place. A shroud 28 provides for air cooling of a cap 26 which secures discs 8, 19 and 22 to body 1. Specification 223,863, [Class 75(i)], is referred to.