In this investigation leading multiphase CFD models (MFIX, FLUENT, and Barracuda) are used to investigate the behavior of large scale cold flow circulating fluidized beds (CFB's). Experimental data from the CFB's is used to compare computational predictions of the different multiphase models. In addition, computational cost, model set-up, and post-processing advantages and disadvantages of the different models, with respect to large scale CFB's, is presented.