Title:
Refill Strategy for Two Tank Gold Gas Propulsion Systems
Refill Strategy for Two Tank Gold Gas Propulsion Systems
Author(s)
Wood, Samuel
Advisor(s)
Lightsey, E. Glenn
Editor(s)
Collections
Supplementary to
Permanent Link
Abstract
Cold gas propulsion systems using a saturated liquid-vapor mixture as propellant often use
separate tanks for storage and actuation. The pressure of a plenum is regulated via refills from
a storage tank. Without a propellant management device, simple pressure-controlled refills
can inject unwanted liquid into the plenum. This phenomenon leads to unpredictable thrust
and a lower-than-expected specific impulse. These undesirable characteristics are mitigated
by using a model-based closed-loop refill strategy. A valve flow equation is combined with
system characterization data to approximate the average mass flow between the storage tank
and plenum. Refill valve opening and closing times are controlled to allow the system to reach
steady state prior to refilling or actuating. Controller operation is tested and validated on
integrated cold gas systems in orientations that allow either liquid or gas to be in contact
with the plenum refill port. These simulated worst-case and best-case on-orbit conditions are
tested across the system’s full temperature operating range. This paper describes the model
development, integrated hardware testing, and improved system performance associated with
the model-based plenum refill strategy. These findings enable two-tank cold gas propulsion
systems using pressure-controlled refilling to deliver more repeatable system operation.
Sponsor
Date Issued
2023-05-01
Extent
Resource Type
Text
Resource Subtype
Masters Project
Rights Statement
Unless otherwise noted, all materials are protected under U.S. Copyright Law and all rights are reserved