Research on Micro-Propulsion Performance of Laser Ablation ADN-Based Liquid Propellant Enhanced by Chemical Energy

The vigorous development of micro–nano satellites urgently requires satellite-borne propulsion systems as support. Pulsed laser ablation micro-propulsion can meet these high demands. Ammonium dinitramide (ADN), as a green monopropellant, can serve as the working substance for laser ablation. This work investigated the micro-propulsion performance of liquid propellants composed of ADN and water with different ADN mass fractions, aiming to clarify the enhancement effect of chemical energy. Through the single-pulse impulse measurement, the results show that the 70 wt.% ADN had a maximum specific impulse of 167.55 s, a 19% increase compared to H2O. The established semi-empirical model of the micro-propulsion performance fits well with the experimental data and can effectively explain the variations in the patterns of the propulsion’s parameters. The chemical energy’s actual rate of contribution to the increase in the kinetic energy was positively correlated with the ADN’s mass fraction and negatively correlated with the laser energy, with an actual contribution rate of 36% for 70 wt.% ADN at a laser energy of 60 mJ. Furthermore, based on the relationship between the ablation efficiency, chemical-specific energy, and laser specific energy, it was found that the ablation efficiency can be improved by increasing the chemical specific energy and reducing the laser specific energy while ensuring the breakdown. This work provides a scientific approach to quantitatively analyze the enhancement in the propulsion’s performance by chemical energy in laser micro-ablation, which is expected to be extended to other energetic liquid propellants.