Development of the Fluid Dynamic Mass Gauging (FDMG) System



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2024 International Conference on Environmnetal Systems


Acquisition of accurate measurements of unknown volumes of liquid in a rigid tank is particularly challenging in microgravity and, historically, has required extensive instrumentation and equipment to accomplish. The Fluid Dynamic Mass Gauging (FDMG) system developed in this work, is an automated, versatile, and lightweight system that was developed through the application of mass transfer, thermodynamic, and fluid dynamic principles. While the physics involved is complicated when examined in detail, the operational principle of the system is simple as it relies on the linearity in the relationship between a tank's ullage volume and the time required to change the pressure in the tank (referred to as pressure change time). In this work, the development process, and operational principles of the FDMG system are described, and results from the initial testing of the system are presented. Furthermore, the feasibility of using a single point calibration methodology, whereby the tank's volume capacity and pressure change time data acquired when the tank has no more usable water is used to calculate the relationship between ullage volume and pressure change time, was demonstrated. In the initial testing of the system, the automated FDMG system has demonstrated high accuracy in determining the liquid volume within a 75 L ProSource tank when operated at low pressures (the root-mean-square deviation (RMSD) between observed and predicted values was less than 0.5 L for ullage volumes less than 75 L, less than 0.1 L for ullage volumes less than 30 L, and less than 0.05 L for ullage volumes less than 10 L).


Sofia K. Fanourakis, NASA Ames Research Center, USA
Jurek Parodi, NASA Ames Research Center, USA
John Abdou, NASA Ames Research Center, USA
John Vance, NASA Ames Research Center, USA
Lance D. Delzei, NASA Ames Research Center, USA
ICES303: Physico-Chemical Life Support- Water Recovery & Management Systems- Technology and Process Development
The 53rd International Conference on Environmental Systems was held in Louisville, Kentucky, USA, on 21 July 2024 through 25 July 2024.


liquid measurement, volume measurement, microgravity, water management