Microcooling channel effect on a monopropellant microelectromechanical system thruster performance

摘要

As an alternative for the thermal management of fragile materials used for microthruster fabrication, the use of microcooling channels was considered and the effect of the cooling channels on microthruster performance was investigated. Two microthrusters were fabricated with and without cooling channels. The experimental test results showed differences in the thrust generation and temperature variation between the two microthrusters. The surface temperatures of the microthruster with microcooling channels successfully decreased during operation, and the average surface temperatures were lower than that of the uncooled thruster by as much as approximately 58%. However, the thrust generation also decreased by 31%, owing to the lower reaction temperature of the catalyst in the chamber. The experimental results indicated the normal operation of the two microthrusters and the effectiveness of the cooling channels applied to the glass structure for thermal management. There was, however, a decrease in performance due to the characteristics of monopropellant thruster, which has a catalyst in the chamber with a reaction rate that is affected by the surrounding temperature. Therefore, when cooling channels are used, especially in a monopropellant microthruster, additional considerations are required to address the tradeoff between the cooling effect and thrust generation.