Propellant Gauging for Exploration

You are here: Homepage > Search

Propellant Gauging for Exploration

G. A. Zimmerli

This paper presents a brief overview of propellant gauging needs and requirements in the context of lunar exploration missions defined by the Exploration Systems Architecture Study (ESAS) report. A timeline for the development and testing of gauging technologies, and a few key design review dates are presented. A lunar exploration mission scenario is discussed which aids in defining the propellant gauging needs. The fleet of new exploration vehicles includes the Ares I and Ares V launch vehicles, Earth Departure Stage (EDS), Lunar Surface Access Module (LSAM) ascent and descent stages, and the Orion Crew Exploration Vehicle (CEV). The liquid propellant choices are currently oxygen - hydrogen for the launch vehicles, the EDS, and LSAM descent module; oxygen - methane for LSAM ascent module; and monomethylhydrazine nitrogen tetroxide (MMH-NTO) for the CEV. Estimated tank sizes, temperatures, pressures, and storage durations are presented. A baseline propellant gauging system is proposed that is based on high Technology Readiness Level (TRL) gauging technologies. In order to be considered for use on the new exploration vehicles, any new gauging technologies will have to show a clear benefit over the baseline methods in terms of performance and/or cost.