Recently, circulating fluidized bed technology has been greatly developed. For its favorable operation characteristic, circulating fluidized bed boiler is considered to be the first choice for burning anthracite. But due to its complex flow field, there is a problem to fully understand circulating fluidized bed system, especially for flow hydrodynamics, combustion and abrasion properties. Besides, existing researches are almost confined to round cross-section, so it's necessary to get a detailed st...