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To solve the problems of low blending efficiency and poor consistency of blending uniformity in the precision fertilization process,four flute-wheels variable rate fertilization distributor with the secondary collision blending device was designed. It could change the speed of four flute-wheels to variable rate fertilization according to the fertilizer demand. And the secondary collision blending device could uniform blend of different rates of fertilizer without mechanical. The hygroscopic saturated moisture content, adhesive force and breaking force were measured under different moisture contents. Hertz-Mindlin no slip particle contact model of discrete element was used to analyze the regularity of four kinds of fertilizer particles in collision blending process. By means of orthogonal test and analysis of variance, the results showed that there was no significant effect on the standard deviation of blending when the speed of flute wheel was in the range of 20~80r/min and the four flute-wheels fertilizer distributor could blend four kinds of fertilizer evenly. The optimal height of the cone in secondary collision blending device was 12.1mm.Under this condition the cone angle of the cone was 57.9°. When working it was found that the pressure on the fertilizer particles was less than the break force compared with the force distribution of the fertilizer particles calculated by the force chain, fertilizer particles would not be broken in collision blending process. Besides, The high-speed photography were used to analyze the influence of vibration with different frequencies and amplitudes on the collision blending performance of four flute-wheels fertilizer distributor. It was found that vibration had little influence on working process. The collision blending test was carried out, the test results showed that the blending uniformity was basically the same, and the designed fertilizer distributor could achieve variable rate fertilizer blending and non-mechanical blending of four kinds of fertilizers.