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Considering the problem that the each seeding quantity consistency variability of air-assisted no-tillage planter for rapeseed and wheat is affected by the change of land slope, a prototype of even seeding turbine which was suitable for distributor device driven rotation by conveying airflow was developed. The influence law of inlet and outlet working angles of even seeding turbine on the velocity of conveying airflow were analyzed. The key parameters affecting the working characteristics of three kinds of even seeding turbine were determined. The effects of three kinds of even seeding turbine on the distribution of conveying airflow and the rotating speed of even seeding turbine were compared and analyzed by using the dynamic mesh model in CFD simulation and bench test. The simulation results showed that the even seeding turbine with acute inlet and outlet working angles could improve the transportation and mixing performance of seeds. The effect of even seeding turbine with 4, 6, 8 and 10 impellers on the airflow field distribution in the distributor device was carried out. The simulation results indicated that with the increase of the number of impeller, the stability and uniformity of the airflow distribution at the outlet of the even seeding turbine could be improved. The intelligent test platform for planting machines was used to simulate the effect of even seeding turbine with different numbers of impeller on the each seeding quantity consistency variability in field operation with different land slopes. The bench test results indicated that when the rotating speed was 20~50 r/min, the swing angle in one-way combination of the front or rear, and lateral, the reciprocating swing combination of front or rear, and lateral along the operation direction of the planter was relatively flat, the land surface was changed from -5°to 5°, and the number of impeller was 8, rapeseed and wheat had the lowest consistency variation coefficient of each seeding quantity. The consistency variation coefficient of each seeding quantity of rapeseed and wheat were 4.99%~5.82% and 3.85%~4.92%, respectively. When the swing angle in oneway combination of the front or rear, and lateral was 5°, the consistency variation coefficient of each seeding quantity of even seeding turbine with 8 impellers was 7.53 and 11.98 percentage points lower than that of non impeller as seeding rapeseed and wheat. It could meet the requirements of rapeseed and wheat seeding when the land slope was changed.