Gas Motion in a Vertically Vibrated Liquid-Filled Cylinder

When a closed cylinder containing liquid and a small amount of gas is vibrated vertically, stable gas regions can form at the upper and lower ends. Cylinders with diameters of 1-3 cm and heights of 5-10 cm are filled with 20-cSt silicone oil and ambient air and driven by vibrations with frequencies of 50-300 Hz and amplitudes up to 30 G. A model including the vibration-induced Bjerknes force on gas bubbles is developed. This model shows that increasing the amplitude decreases the upper gas region and increases the lower gas region until their sizes become equal. However, it also shows that the lower gas region decreases as the initial gas distribution is biased toward the upper end. Possible causes for this unexpected behavior are discussed. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525. This paper describes objective technical results and analysis. Any subjective views or opinions that might be expressed in the paper do not necessarily represent the views of the U.S. Department of Energy or the United States Government.