Sector Tests of a Low NOx, Lean-Direct-Injection, Multipoint Integrated Module Combustor Concept

TLDR

The study tests a multipoint lean‑direct‑injection combustor with 36 fuel injectors and integrated module construction using chemically etched, diffusion‑bonded laminates, operating at inlet temperatures up to 866 K, pressures up to 4.8 MPa, and Jet A fuel. A correlation between NOx emissions and inlet temperature, pressure, and fuel‑air ratio is developed, showing that a 55:1 pressure‑ratio engine would emit less than 40 % of the 1996 ICAO NOx standard.

Abstract

Results of a low-NOx combustor test with a 15° sector are presented. A multipoint, lean-direct injection concept is used. The configuration tested has 36 fuel injectors and fuel-air mixers in place of a dual annular arrangement of two conventional fuel injectors. An integrated-module approach is used for the construction where chemically etched laminates that are diffusion bonded, combine the fuel injectors, air swirlers and fuel manifold into a single element. Test conditions include inlet temperatures up to 866K, and inlet pressures up to 4825 kPa. The fuel used was Jet A. A correlation is developed relating the NOx emissions to the inlet temperature, inlet pressure, and fuel-air ratio. Using a hypothetical 55:1 pressure-ratio engine, cycle NOx emissions are estimated to be less than 40% of the 1996 ICAO standard.