Based on?the?fundamental?principle?of?classical mechanics?and?hydromechanics,?a particle-trajectory?model?was?established to simulate transport process?of?particles?in?J/E?chamber?during the?preparation?of?micropowder with a combination of jet milling and electrostatic dispersion techniques,?and?the law of kinetic?of the particles during?J/E?process?was revealed?as well.?When the charging voltage is?20 kV, the?grain flows?of micropowder present?laminar?flows of?quasi-steady-state?as?the?velocity of jet is low.?With the increase of jet velocity, the distribution of particles?transforms?into?dispersive?state,?and?the dispersion enhances to a certain extent. While when the charging voltage increases to 60 kV,?the dispersion of particles in the chamber?is further improved, which presents?a better evenly dispersed state.?The simulation of flow dynamics of the particles shows that?increasing the jet velocity and the charging voltage can improve?the dispersiveness of the powder during the transport process in?the?J/E?chamber, and the effect of the charging voltage is more?substantial.