Cryogenic liquid helium sloshing dynamics driven by spacecraft orbital accelerations associated with spinning and/or slew motions

摘要

The formulation of sloshing dynamics for partially filled liquid of cryogenic superfluid helium 2 in dewar containers driven by both the gravity gradient and jitter accelerations associated with spinning and/or slew motions in a microgravity environment are investigated. Both Gravity Probe-B (GP-B) and Advanced X-Ray Astrophysics Facility-Spectroscopy (AXAF-S) spacecraft are given as realistic examples to elaborate the spacecraft operated with spinning and/or slew motions in which cryogenic superfluid helium 2 is used as a propellant. The jitter accelerations include slew motion, spinning motion, atmospheric drag on the spacecraft, spacecraft attitude motions arising from machinery vibrations, thruster firing, pointing control of spacecraft, crew motion, etc. The numerical computation of sloshing dynamics is carried out with the formulation of the noninertia frame spacecraft bound coordinate, and solving time-dependent, three-dimensional formulations of partial differential equations subject to initial and boundary conditions. Examples are given to demonstrate how sloshing dynamics affect liquid-vapor interface oscillations of cryogenic superfluid helium 2 driven by orbital accelerations of spacecraft associated with spinning and/or slew motions.