微重力环境中重力梯度加速度引起的流体晃动运动

Gravity Gradient Acceleration Induced Fluid Sloshing Motion in Microgravity Environment

本文研究了关于旋转轴在贮箱的非对称轴上且远离贮箱的几何中心情况下，流体在微重力环境中由重力梯度加速度诱发的晃动特性，建立了问题的数学模型并对模型进行了数值模拟。以高级Ｘ射线天文物理实验卫星（简称ＡＸＡＦ─Ｓ）作为研究对象，获得了由旋转运动引起的重力梯度加速度的数学表达式。晃动问题的数值计算以与卫星固连的非惯性坐标系为基础，目的是寻求一种较为易处理且适合于流体力学方程的边界和初始条件。通过数值计算获得了流体作用于卫星贮箱上的力和力矩。

The mathematical model of spacecraft sloshing for a partially liquid fill cryogenic helium in Dewar container diven by the gravity gradient acceleration associated with slew motion is studied in this paper. An Advanced X-Rad Astrophysics Facility Spectroscopy spacecraft is chosen as an example in this study. Explicit mathematical expressions which manage orbital gravity gradient acceleration associted with slew motion acting on the spacecraft fluid systems are derived. The numerical computation of sloshing dynamics is based on the non-inertial frame spacecraft coordinates and intends to seek the solution of time-dependent,three-dimensional formulations of partial differental equations subject to initial and boundary conditions. The numerical computation of fluid forces and moment fluctuation exerted on Dewar container are investigated. This study discloses the sloshing dynamic liquid-vapor interface fluctuations, fluid forces and moment fluctuations exerted on the spacecraft system.