| OCR Text |
Show (23) iterative method . The solution procedure can be summarized as follows: • A solution is initiated by iteratively solving the gas phase equations using known boundary conditions and by assuming no particles. • The particle conservation equations are solved and define particle trajectory, velocity, temperature, and mass. Source terms for gas phase conservation equations are calculated and radiative properties are established. • The radiative transport equation is solved, and source terms for the energy equation are computed. • Gas phase conservation equations are again solved with source terms from particle and radiation equations. • Iteration is performed returning to the second step until convergence is achieved. RESULTS AND DISCUSSION The aim of this paper is to present predictions of pulverized coal combustion. However, it is useful to investigate the case of gas phase combustion because of the numerous practical applications in industry. In addition, the accuracy of the computer code was evaluated by comparing gas phase combustion predictions with predictions of an established computer code using the same modeling assumptions. Gas Phase Combustion The application of the combustion model, COMO, to the simpler gas combustion case requires that we neglect, particle phase equations and solve only the equations described In the gas phase transport equations section. Thus we solve equations for continuity, three components of momentum, turbulent kinetic energy and its dissipation, enthalpy, radiation, mixture fraction and its variance as well as the ideal gas rule for density. -14- |
