Moving Two-Fluid Systems Using the Volume-of-Fluid Method and Single-Temperature Approximation

Abstract

I.Introduction SLOSHING experiments using cryogenic liquid nitrogen, executed at the Centre of Applied Space Technology and Microgravity(ZARM) in Bremen, Germany, were simulated numerically using a computational fluid dynamics (CFD) program based on the volume-of-fluid (VOF) method and a single-temperature-per-cell approximation. In contrast to sloshing of storable liquids (a fluid that is in the liquid phase at room temperature and pressure), sloshing of a cryogenic liquid introduces important thermodynamic effects in addition to the dynamical aspect of a sloshing motion.The dynamic behavior of a sloshing liquid has been extensively studied[1], whereas the thermodynamic aspects have not been the subject of many studies and are not understood well. Therefore, the focus of the experiments and simulations is on these thermodynamic aspects. It will be shown in this Note that codes using the previously mentioned methods are not able to simulate the thermodynamic aspects of such experiments accurately, and it will be explained why that is the case.