Due to limitations of laboratory scale, the bending pipe structures inevitably exist in the indoor experimental loop of sequence transportation which will carry out batch transportation contaminated mechanism research. In order to optimize the design of the experimental loop, a two-dimension model was established aiming at the structure of fillet and circular were elbow, thus how the two structures affected the mixing process of sequence transportation by Fluent was simulated. The results showed that the flow field of different scales could be formed at the elbow of the loop, and the low velocity region could be formed from the inner side of the elbow, therefore severe disturbance with mixture quantity increased. Compared with the arc elbow, the mixture quantity of 90 degree bend structure could reach more than 12%. This study had important guidance for the design of the order of the product.

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