Testing Of A Solid Fuel Adamantane Ion Thruster

The goal of this work is to experimentally evaluate the effectiveness of solid Adamantane, C₁₀H₁₆, as a propellant for an ion thruster operating in vacuum conditions. Our motive is the development of a single-use electric propulsion system for the deorbiting of low-Earth orbit spacecraft, which increases or maintains similar thrust compared to current technology, while reducing complexity. A prototype thruster was constructed from a non-conductive tube 0.5 inches in length, with a conductive surface capping either end, and an exit orifice 0.05 inches in diameter. Approximately 0.05 g of adamantane was placed inside the tube. Initial tests were conducted in a vacuum chamber depressurized to 50 mTorr. A 1 kV potential difference was applied to the conductive end caps, and an ion plume was observed coming out from the orifice. Further experiments will be conducted on the prototype thruster using a pendulum to indirectly measure its thrust. A 4 cm² aluminum foil pendulum is suspended from the top of the vacuum chamber by a light, uninsulated copper wire, and positioned 2 cm in front of the exit orifice. The pendulum’s displacement is used to calculate thrust. The system is also simulated numerically using the open-source Starfish software.