This report presents a summary of the work accomplished in a multiyear study conducted for the US Department of Energy, Morgantown, Energy Technology Center, under Contract No. AC21-85MC220262. In this project existing models for hydrodynamic mixing in fluidized beds are used in a representative process design and development scenario for the KRW gasifier. The particular emphasis in this study is upon the use of two modeling approaches: the dimensional analysis and scaling of fluidization data, and the application of the finite difference hydrodynamic model CHEMFLUB. Predictions of hydrodynamic mixing in the KRW reactor are made. The relative value and practicality of the two different models for predicting hydrodynamic mixing are assessed through comparisons with experimental data. 75 refs., 29 figs., 9 tabs.