the cone height of the CB FSB was the main factor among the three structural parameters (Table 1). With regard to this single factor, the effects of different cone-height levels on bed expansion can be expressed as A1, A2, and A3; within this scope, the higher the cone height, the larger the bed expansion. The order of effects of different cone diameter levels was B3, B2, and B1; within this scope, the smaller the cone diameter, the larger the bed expansion. The order of effects of different slot width levels was C3, C2, and C1; within this scope, the smaller the slot width, the larger the bed expansion. These were consistent with the conclusions of preparatory work about design. The objective of the present study was to pro-pose optimization solutions using an orthogonal test method. For instance, with bed expansion as the critical evaluation index, the optimization solution for structural parameters was determined to be the combination of A1-B3-C3. At the same time, the inflow superficial velocity through a cross-section of the CB FSB was 2.71 cm/s, and the bed expansion reached 122%.In addition, numerical simulation can further analyze problems for which experimentation alone cannot yield accurate results. Numerical simulation also can show the effects of different factors on the flow field in the CB FSB. This approach provides a theoretical basis for the production of the CB FSB.