It has been observed under certain flow conditions that there is a measured increase in fine particle concentration at the center of the circulating fluidized bed riser just below the exit to the cyclone. It is hypothesized that the Saffman force might be responsible for this phenomena. Therefore, this research paper discusses the likelihood of the existence of "Saffman" forces, or lift due to viscous shear, in cylindrical, circulating fluidized bed (CFB) risers operating in the core annular regime. Published by Elsevier B.V.