GB654932A - Improvements in or relating to combustion-chambers for gas-turbines - Google Patents

Abstract

654,932. Liquid-fuel burners. ROLLSROYCE, Ltd. Sept. 9, 1946, No. 27049. [Classes 75(i) and 75(iii)] The combustion chamber of a gas turbine engine is provided with a high capacity main burner and a low capacity auxiliary burner which operates throughout the full range of operating conditions of the engine to deliver fuel in a finely atomized spray into a region of the chamber into which the main burner also delivers fuel and either the auxiliary burner is structurally separate and spaced from the main burner, the arrangement not including a vaporizer for the main fuel burner or the latter is located downstream of the auxiliary burner and delivers fuel upstream and the auxiliary burner delivers fuel downstream. The combustion chamber comprises an outer air casing 10 having a neck 12 for the entrance of air and an inner casing forming a flame tube 11 with apertures 14 and a central port 13 for the supply of primary air. Air also flows between the two casings, part of this air entering the flame tube through apertures 16 to provide secondary air. A low capacity atomizing burner 17 is mounted in the central port 13 to spray fuel with the airstream and a high capacity burner 18 is mounted in the sidewall of the combustion chamber to spray fuel against the airstream. Both burners are supplied by. a fuel pump 19 but the fuel pressure at the low capacity burner 17 is maintained higher than that at the main burner 18 by a spring-loaded valve 21 in the pipe leading to the main burner. Swirl vanes 15 are provided in the air port 13.