This study addresses parameter identification in a one-dimensional spacecraft propulsion system. We focus on the speed of sound of the fluid and the volume of remaining gas bubbles in the feed lines, both of which have large impact on the time-series pressure dynamics. Pressure time-series data are transformed into frequency responses to investigate which spectral features are most informative for the objective function used in the parameter identification. The objective function derived in this study was validated in twin-experiment study. The results demonstrate the speed of sound and the bubble volume were successfully identified by the proposed objective function.
Hamato et al. (Wed,) studied this question.