Influence of Surface Radius Curvature on Laser Plasma Propulsion with Ablation Water Propellant**supported by National Natural Science Foundation of China (No. 10905049) and Fundamental Research Funds for the Central Universities of China (Nos. 53200859165, 2562010050)

Abstract

The surface shape of liquid water is well controlled during nanosecond pulse laser ablation plasma propulsion. In this study, we measured the effect of the shape on the coupling coefficient and the specific impulse. We found that the coupling coefficient and specific impulse could be optimized by varying the surface convexity. Based on the analysis of the surface radius curvature, we demonstrate that the convex surface changes the laser focal positions to achieve high efficiency.