CFD Jet Mixing Model Validation against Zero-Boil-Off Tank (ZBOT) Microgravity Experiment

A CFD model for simulating the fluid dynamics of the jet induced mixing process is utilized in this paper to model the jet mixing portion of the Zero Boil-Off Tank (ZBOT) experiment in microgravity [1]. The Volume of Fluid (VOF) method is used for modeling the dynamics of the interface during mixing. The simulations were performed at different jet speeds and liquid fill levels. The effects of the jet angle and orientation, values of gravitational acceleration and surface tension, as well as the discretization scheme used with the volume fraction equation on the jet-ullage interaction were studied and discussed in this paper. The computational results for the jet-ullage interaction are compared with images taken during the experiment. A qualitative comparison shows that the CFD model was able to capture the main features of the interfacial dynamics, as well as the jet penetration of the ullage at different jet speeds and liquid fill levels.