Computational Science

Steady and Unsteady Laminar Diffusion Flame by Newton's Method


Description: Diffusion flames are frequently encountered in practical combustion devices, such as jet turbines and commercial burners. A desired combustion device should be efficient in energy transfer and produces few pollutants. Studying the mechanism of diffusion flame is very helpful in achieving the goal of high efficiency and low pollution combustion. With the improved computing capability of computers, numerical simulation plays an increasingly important role in exploring the mysteries of physical world, such as multi-dimensional diffusion flame, which combines fluid flow and chemical reaction. The governing equations of diffusion flames are strongly coupled and characterized by the presence of stiff source terms and nonlinearities. We applied compressible Navier-Stokes equations with one-step irreversible chemical reaction to simulation the diffusion flame, and discretized the equations by finite difference method. To save computation time, we applied a three level multigrid method for steady flow, and the resulting algebraic equations are solved by the iterative solver Bi-CGSTAB with Gauss-Seidel as preconditioner.