GB1392739A - Devices for pre-vaporising liquid fuel - Google Patents

Abstract

1392739 Gas turbine engine combustion equipment SOC NATIONALE D'ETUDE ET DE CONSTRUCTION DE MOTEURS D'AVIATION 3 July 1972 [16 July 1971 28 April 1972] 30974/72 Heading F1L [Also in Division F4] A pre-vapourizing liquid fuel injector 7 for use in a combustion chamber has a generally T-shaped structure formed by a body portion 12, Fig. 6 to which comburant, such as air, and fuel are supplied, and two transverse arms 13, 14 communicating with the portion 12 via a restricted opening 54 defined between sharp edges 52a, 53a of partitions 52, 53 located in the region of the junctives 13x, 14x where the arms 13, 14 join the portion 12. The partitions are said to produce a more uniform wetting of the interior walls of the arms 13, 14 by the fuel/air mixture, the fuel being vapourized by contact with these walls which are heated by the combustion flame, particularly in regions around 13x, 14x and result in a more uniform vapour/air mixture discharged at orifices 15, 16. Liquid fuel is sprayed into body 12 and mixes with primary air a 1 , the fuel being atomized by the air blast, such atomization being enhanced by acceleration of the air-flow through opening 54, and by mechanical atomization due to shock effects at sharp edges 52a, 53a. The partitions 52, 53 may be located at the level of the points of junctive 13x, 14x, Figs. 4, 5 (not shown), and may have holes (55), (56) to supply a portion of the fuel/air mixture directly to regions around 13x, 14x without passage through opening 54. Alternatively the partitions may be formed downstream of junctives 13x, 14x, relative to the flow direction through portion 12, being located on the end of a sleeve 12a formed with by-pass passages 60 feeding regions around 13x, 14x directly. A GAS TURBINE may have a plurality of such injectors 7, Fig. 1, in an annular combustion chamber 2a, 2b, having an air supply conduit 8 giving primary air through orifices 5, 6 and secondary and dilution air through orifices 9a, 10a, 11a, air through orifice 9a giving rise to recirculation. Each injector 7 is mounted coaxially with a respective orifice 6 by means of a member 18, which may be integral with body 12 and defines annular passages 21, 22 through which part of the primary air passes, air through passage 21 acting as thermal insulation for the upstream end of body portion 12.