Experimental study on flow field distribution and material separation characteristics in a pneumatic potato impurity removal device based on CFD-DEM coupling - Zhihao Tian; Zhongcai Wei; Yubo Liu; Guoliang Su; Zhen Cui; Faming Wang; Xiangcai Zhang; Xianliang Wang; Xiupei Cheng; Xiuhong Wang; Chengqian Jin (Computers and Electronics in Agriculture, 2026)