Experiment and simulation study on optimized structure of a gravitational air classifier

•The dispersion structure double breaks up the feed.•The double layers improve the fluid-flow characteristics.•Circulating fan is applied.•The optimal structure is helpful to improve classification efficiency.•The optimal structure reduces energy consumption.

We carried out focusing on the experiments and simulations of a gravitational air classifier, whose classifying chamber is designed into four different dispersion structures. Through the experiments, the classification performance in the classifier chamber was acquired after that feed rate was determined. And then using the Fluent, a two-dimensional computational fluid dynamics was developed. The flow field characteristics and air classification performance were presented and evaluated. We investigated the three important influent factors, including the dispersion structures, the feed rate and the frequency of the fan. Finally, with the experiment and simulation being analyzed, the optimal dispersion structure has been obtained.