Numerical study on the flow field and separation efficiency of a rotary drum separator

In this paper, a new device called rotary drum separator consisting of multi-layer channels is introduced in gas–liquid separation. First, the flow field, including the distributions of pressure and gas velocity at different gas inlet velocities and rotational speeds, is numerically studied. Then, the influences of the inlet velocity, rotational speed, channel shape and size on separation efficiency are discussed by the discrete phase model. The results show that the inlet velocity and rotational speed play a critical role in pressure distributions. Besides, the tangential velocity is linear with the radial position. In triangular channels, the separation performance is better than that in circular and square channels when droplets are larger than 4 μm, and it can be improved by decreasing the radial height or increasing the drum length. Nevertheless, for fine droplets smaller than 4 μm, the separation efficiency is almost independent of the channel shape and size. Additionally, decreasing the inlet velocity or improving the rotational speed is beneficial to increase the efficiency, and improving the rotational speed can also greatly reduce the cut-off diameter.