Although CFD-DEM simulation of Geldart B and D particles has been experimentally validated extensively, its experimental validation for simulating the hydrodynamics of Geldart A particles has been seldom reported, due to the fact that even the particle number in a laboratory fluidized bed is too much to be tracked individually. In this study, one-to-one comparison between experimental and CFD-DEM study of a miniaturized gas-solid fluidized bed (micro-fluidized bed) containing FCC particles was performed. It was shown that the bed expansion characteristics in bubbling fluidization regime, the mean voidage of emulsion phase as well as the bed collapse process can be predicted accurately by CFD-DEM method. The results not only provide experimental validation of CFD-DEM method for studying the heterogeneous dynamics of Geldart A particles in bubbling fluidized beds, but also prove that CFD-DEM method is an ideal and powerful tool for exploring the behavior of micro-fluidized beds. (c) 2021 Elsevier Ltd. All rights reserved.