Development and ground tests of a 100-millinewton hydrogen peroxide monopropellant microthruster

A hydrogen peroxide microthruster for maneuvering the attitude of small satellites is developed by first studying the outstanding problems of the miniaturization of thruster systems, such as the enhanced heat loss and decomposition instabilities of bubbles in liquid. Theoretical analysis is employed to determine the test and design parameters of the hydrogen peroxide microthruster. The design concept of a 100-mN hydrogen peroxide microthruster is proposed, and the microthruster is demonstrated to perform a minimum impulse bit of 10^-2 N - s, which can provide a microsatellite slew at a speed of 0.1 deg/s. The total volume of the microthruster prototype is about 0.9 cm³, with a throat diameter of 0.5-mm packing, with silver flake as the catalyst, sad 92% hydrogen peroxide is adopted with a flow rate of 0.18 g/s. Measurements of the ignition delay at different catalyst-bed preheating temperatures are compared to define the operating parameters for practical applications. Test results show that the hydrogen peroxide microthruster gives a good c* efficiency and a short ignition delay compared with the performance of large-scale systems. Under atmospheric pressure at sea level, the developed microthruster can produce 182 mN with a specific impulse of 101 s.