The Effect of Numerical Diffusion on Gas-solids Fluidized Beds and the Use of Deferred Correction in a Finite Volume Method to Stabilize High Order Discretization of Convection Terms

First order methods are commonly used in numerical simulations of gas-solids fluidized beds because they are both stable and affordable. Unfortunately, because of the large amounts of numerical diffusion inherent to these methods higher order methods are recommended to accurately predict bed dynamics e.g., voids or bubbles. The deferred correction method and the downwind factor method are both used for generating linear equations based on a 7-point stencil from higher order discretization formulas. Deferred correction significantly improves the computational speed over the downwind factor method while achieving the same degree of accuracy and under certain conditions allowed computations which the downwind factor method failed.