Analysis of electron bubble dynamics inside an electrohydrodynamics nozzle using molecular simulation

The dynamics of charge carriers inside an electrospray nozzle for insulating liquids is studied using 3-D molecular dynamics (MD) simulation. The main aim of the present study is to relate the respective contribution of charge carrier to the spray and leakage currents respectively. This paper presents the reasons why the electrical stability of recently introduced side-to-center (STC) electron injection technique is more stable in comparison with parallel injection technique used in the past. The calculation result shows that the dynamics of the EB around the needle tip is different in comparison with that of the region down stream of the flow. These are classified into the large electric field region (around the needle tip) and the weak electric field region (down stream of the flow). In the weak electric field region, the EB becomes an unpredictable random motion and the EB dynamics is dominated by the liquid flow. The dynamics of the EB near the needle tip primarily contributes to the spray current. The space charge inside the nozzle brings the EBs outwards near the nozzle surface from its central region. The EBs, which consists of stable cluster with surrounding liquid molecules contribute to the spray current.