COMBUSTION OF REFORMED GAS AND LIQUID FUEL IN CRGT COMBUSTOR

Numerical simulations of four combustion processes in a dual-fuel combustor of chemically recuperated gas turbine (CRGT) were carried out in this work. The fuels in the four combustion processes were liquid fuel, liquid fuel + steam, liquid fuel + reformed gas and reformed gas, respectively. The mathematical models adopted for different fuels combustion consist of realizable k-epsilon turbulence model and probability density function (PDF) model. The temperature distribution, species concentrations and NO emission were obtained. The results show that the fuels can burn effectively in the dual-fuel combustor for CRGT. Compared with the liquid fuel combustor, the flame temperature, average temperature of combustor wall and NO emission are reduced by 7,8 %, 4,8 % and 75,3 % respectively when the steam is injected into the combustor. However, they are reduced more when the liquid fuel is replaced by reformed gas, which are 10,3 %, 5,6 % and 97,2 % respectively. A little deterioration of the overall temperature distribution of combustor outlet is obtained for liquid fuel + steam combustor, while a better temperature distribution of combustor outlet is obtained for reformed gas combustor, in comparison with liquid fuel combustor.