Shunsuke Amano

Feasibility Study on a Low NO_x Combustion with Forced Recirculation Flow Formed by an Upward Swirl

A new concept of combustion liquid fuel suitable for Gas Turbine combustor was investigated. Combustion in high temperature and low oxgen concentration by Burnt Gas Recirculation (BGR/ FGR/EGR) is an important technology for low NOx combustion of liquid fuel. Upward swirl was focused to produce forced recirculation flow of burnt gas. A combined method of analytical approach (Computational Fluid Dynamics : CFD) and experimental approach was used. Flow pattern produced by the upward swirl introduced into combustion zone from the direction of combustion zone exit was investigated. CFD showed that a kind of guide vanes to produce flow to inside of radial direction at the top of combustion zone had important role for the upward swirl to recirculate fully to the top of combustion zone. A prototype combustor with the design based on results of CFD with and without combustion was made and tested. Non-luminous flame was observed at lean combustion condition. These results showed that this new concept of the primary zone had a high potential as a low NOx combustion technology of liquid fuel.