NUMERICAL SIMULATION OF A 50 KW CLASS OXY-FUEL BOILER

摘要

A numerical simulation has been conducted for the flow, combustion and heat transfer in the combustion chamber of a 50 kW class oxy-fuel boiler. Methane is chosen as the fuel, while pure oxygen or air is set as the oxidizer. Momentum and energy equations are analyzed based on the RANS (Reynolds Averaged Navier-Stokes Simulation) with the standard k-　 model. The thermal radiation is considered adopting the P-1 model. Combustion process is treated based on the EDC (Eddy Diffusivity Concept) model. The simulation has been validated against the experiment with the centerline temperature of the combustion chamber. The results show that the oxy-fuel burner can heat the entire combustion chamber due to the gas radiation heat transfer in spite of the significantly reduced flow rate. The concentration of CO2 is predicted to be so high for the oxy-fuel combustion that CO2 can be economically captured just by condensing the vapor.