The Structure Design and Numerical Simulation of Dual-Fuel Gas Turbine Nozzle

Abstract

This paper designed several dual-fuel nozzle structures for the chemically recuperated gas turbine (CRGT) combustor and then the numerical simulation in regard to the combustion flow fields of the combustors with these nozzle structures was carried out with the aid of CFD method and finally the contrastive analysis was made. Realizable k-ε turbulence model, PDF combustion model and the SIMPLE algorithm method were applied in the numerical simulation. According to the contrast of these nozzle structure models’ flame length, position of the high temperature zone, wall temperature and the evenness of exit temperature field as the key influencing factors of the combustor, we could know that the gas swirling dual-fuel nozzle with oblique holes, on the one hand, can produce preswirl flow in the gas channel to enable a better mixing of the pyrolysis gas and air; on the other hand, can protect the nozzle and the wall of flame tube from fire and keep the exit temperature in a moderate level.