A mixing process for a wet particle system is advanced by using fundamental operations such as compression, shearing, rolling, and folding. Here, we present a simulation method based on these fundamental operations in order to quantitatively understand the mixing process even in the microspaces between particles. We developed model experimental apparatus, and a simulation method based on a dispersion model, and compared the results by both methods. Using the model analysis, the mixing process can be quantitatively understood until the micromixing of the wet particles is mutually completed. It was also found that a mixing process proceeds rapidly and that the mixing state proceeds regularly and uniformly using proposed model operation that is dominated mainly by the folding operation.