Bubble shape and rising velocity in viscous liquids at high temperature and pressure

• Published in: Experimental thermal and fluid science 2019-04, Vol.102, p.528-538
• Main Authors: Tian, Zhen, Cheng, Youwei, Li, Xi, Wang, Lijun
• Format: Article
• Language: English
• Subjects: Aspect ratio; Bubble rise velocity; Bubble shape; Bubbles; Correlation; Fluid dynamics; Fluid flow; Gas density; High pressure; High speed cameras; High temperature; Liquids; Paraffin; Paraffins; Pressure; Pressure effects; Reynolds number; Silicones; Stainless steel; Stainless steels; Surface properties; Temperature; Temperature effects; Velocity; Viscosity; Weber number
• ISSN: 0894-1777; 1879-2286
• DOI: 10.1016/j.expthermflusci.2018.12.018

•Bubble shape was experimentally studied at high temperature and pressure.•New correlations for bubble aspect ratio E were proposed by dividing into three parts.•The influence of high temperature and pressure on bubble rising velocity were studied. Industrial bubble column reactors use to operate at high pressure and temperature. However, few experimental investigations have been performed under such severe conditions. In this work the effects of high pressure (0.1–6 MPa) and high temperature (293–473 K) on the bubble shape and rising velocity in silicone oil and paraffin are experimentally investigated. The experiments are carried out in a stainless steel bubble column of 50 mm I.D with three pairs of highstrength quartz windows. The bubble flow is visualized and recorded through high speed camera. New correlations for bubble aspect ratio E are proposed by use of the experimental data. The correlations are divided into three parts in terms of Weber number and Morton number. For We > 12, bubble aspect ratio is independent of Weber number, and is only related to Morton number. For We