FEMTA micropropulsion system characterization by DSMC
Abstract
CubeSats with compact, low-power attitude-control systems open up opportunities for deep-space missions as well as cost-effective constellation-based satellites targeting remote sensing and communication applications. Film Evaporation MEMS Tunable Array (FEMTA) is a micropropulsion technology that employs thermally-controlled surface tension in a microscale capillary for vaporization of liquid water propellant. FEMTA thrusters generate tunable thrust on the order of micro-newton with a thrust-to-power ratio of about 230 µN/W. Because of the small scale capillary on the order of 10 micron and below, the rarefied flow effects are significant for the vapor flow in this system. In the present work, the direct simulation Monte Carlo (DSMC) SPARTA solver is used to numerically evaluate two key aspects of the FEMTA system: a) the evaporation of the propellant in the quiescent system-state, i.e., without heaters actuation, and b) effect of plume expansion on the CubeSat walls to inform thrust cell placement and estimate the extent of plume contamination. Both factors affect the propellant consumption and system lifetime.
- Publication:
-
31st International Symposium on Rarefied Gas Dynamics: RGD31
- Pub Date:
- August 2019
- DOI:
- 10.1063/1.5119560
- Bibcode:
- 2019AIPC.2132g0006J