Abstract: In order to investigate the variation of the standing wave size characteristics of ultrasonically aided electrospray thrusters (UAET), a numerical model of liquid vibration at the emitter liquid surface is established and verified by the standing wave sizes measurement experiments. Comparing the measured and calculated results of the standing wave intervals, it is found that the variation trend of the two can be considered consistent, and the calculation error is less than 6.55%. Based on those above, the numerical model is used to calculate the related size parameters of standing waves with different wave source frequencies and amplitudes. The main conclusion shows that: (1) the standing wave interval, height and radius decrease as the wave source frequency increases, and the inherent reason is that the frequency mainly influences the required time of ripple formation; (2) the increase of amplitude has little effect on the interval, but only leads to the increase of standing wave height and radius, and the inherent reason is that the amplitude has an effect on the average stress of ripple formation.

Key words: Ultrasonically aided electrospray thruster, Standing wave interval, Standing wave height, Standing wave radius, Numerical calculation