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To improve the performance of cleaning device under the condition of large feeding mass of maize mixture, a wave screen for maize grain cleaning was designed based on crank and double rockers mechanism. The concave and approximate flattening of the wave screen were realized by the combined movement of multi-stage screens. Structure of wave sieve was determined based on theoretical analysis. CFD-DEM method was used for numerical simulating the motion of gas-solid two-phase in wave screen cleaning device. A high speed airflow belt could be formed in the upper space in the cleaning device, which was beneficial to the blowing of impurities. The airflow velocity near the wave sieve was decreased first and then increased along the longitudinal direction of wave sieve. The airflow distribution near sieve layer was beneficial to the migration and temporary retention of materials on sieve when sieve group moved in wave mode. Maize grains successively completed the impact on the screen, retention, which were thrown and passed over the screen under the motion of the wave screen, which could improve the efficiency of grain penetrating the sieve hole. The air velocity at the inlet of the cleaning device, the angle of installed screen and rotational speed of drive shaft were selected as the test factors. The loss rate, cleaning rate and screening efficiency of maize grains were selected as test indexes. The quadratic orthogonal rotation combination test was carried out. The mathematical models between factors and indicators were established. The best combination of parameters was obtained as follows: the airflow velocity of cleaning device inlet was 14.6m/s, the angle of installed screen was 8.5°, and the rotational speed of drive shaft was 240r/min. The high-speed camera bench test was carried out. The motion of the grains on the wave screen in the bench test was as same as that in the simulation, which verified the accuracy of the simulation result. When the feeding mass of maize mixture was as large as 7kg/s, the cleaning rate of grains after screening by wave sieve was 99.12%, and the loss rate of grains was reduced by 0.45%. The time of screening 21kg maize mixture was 6.86s, and the mechanism of wave screen could meet the requirement of cleaning large feeding mass of maize mixture.