Improvement on Ignition Performance for a Lean Staged Low NOx Combustor

Abstract

KHI (Kawasaki heavy industries Ltd, Japan) and JAXA (Japan Aerospace Exploration Agency) have been working together since 2004 to improve lean staged concentric fuel injector technologies. One of the weak points of a lean staged fuel injector is said to be ignition / light around performance. Ignition characteristics were assessed on several fuel injector configurations in burner tests. Laser diagnosis, CFD analysis and high-speed video camera recording were used to understand the effect of fuel injector geometry on fuel spray distribution and ignition characteristics. They showed a clear relationship between the burner geometry and ignition characteristics. Light around characteristics was evaluated with the burner configuration optimized in burner tests. Light around performance deteriorated in multi sector unit compared to that in burner test. CFD analysis and some ignition tests with different configuration of combustor gave a clue to restore the light around characteristics deteriorated in multi sector unit.