Combustor arrangement

Abstract

A combustor for a gas turbine engine comprises an annular combustion chamber having radially outer and inner rows of fuel injectors disposed concentrically in the combustor head wall. Injectors in one of the rows are in angular registration with spaces between injectors in the other row. Each fuel injector produces a fuel/air mixture having a swirling motion, and has a downstream mixing duct. Each mixing duct opens into the combustion chamber through the combustor head wall and has a length sufficient to allow at least partial mixing of the fuel/air mixture before entry to the combustion chamber as a divergent swirling stream. Mixing ducts in the first and second rows of injectors have longitudinal centerlines oriented to coincide with generating rays of respective first and second imaginary conical surfaces. These conical surfaces intersect at an included angle within a primary combustion zone in the combustion chamber, whereby injectors located in different rows are angled towards each other in the downstream direction and the divergent swirling streams of fuel/air mixture coming from different rows cross in the combustion chamber in an interdigitating manner. This creates a strong mixing interaction between the streams from different rows and enhances uniformity and rapidity of combustion in the primary combustion zone.