Fig. 1. Working principle of ionic liquid electrospray thrusters

Fig. 2. Prototypes of the array-type ionic liquid electrospray thruster

Fig. 3. Prototypes of the ionic liquid electrospray thrusters developed by the research institutions in China

Fig. 4. Three working processes of an ionic liquid electrospray thruster： cone jet， beam， and plume

Fig. 5. Emission modes of electrospray under different dimensionless numbers^［44］

Fig. 6. Various emission modes of electrospray^［53］

Fig. 7. Structure of the hybrid emitter ionic liquid electrospray thruster

Fig. 8. Phase diagram of the working mode for hybrid emitters^［53］

Fig. 9. Beam structure of electrospray^［44］

Fig. 10. Two neutralization modes of electrospray plumes^［76］

Fig. 11. Half angles of plume divergence under different beam spacing^［80］