Abstract: In order to improve drying effect of the low rank coal drum dryer, optimize the technology and configuration of the drum dryer, prevent the accident of coal dust disaster occurrence in drum dryer. According to the working principle of the low rank coal drum drying, the distribution of the flow field inside the drum dryer is simulated by the combination of hydrodynamic theory and the Fluent simulation software. The pressure field, the velocity field and the temperature field of the gas-solid two-phase flow are analyzed. The results show that the pressure at the inlet wind feeding cover and outlet wind nesting cover of the pressure field is negative, and it is basically conform to reality; The temperature downtrend of temperature field can be divided into three stages from the inlet to the outlet of the drum dryer: the preheating stage, the constant drying rate stage and the decelerating drying stage; the front half part of the velocity field along the direction of exports, radial is gradually reduced, while the second half tends to be stable.