The Drag Coefficient and the Shape for a Single Bubble Rising in Non-Newtonian Fluids

The dynamical characteristic of a single bubble rising in non-Newtonian fluid was investigated experimentally. The bubble aspect ratio and rising velocity were measured by high speed camera. The shape regimes for bubbles in non-Newtonian fluids was plotted by means of Reynolds number Re, Eötvös number Eo and Morton number Mo. The effects of bubble shape and liquid rheological property on the total bubble drag coefficient were studied. A new empirical drag coefficient correlation covering spherical bubble and deformed bubble was proposed, the predicted results shows good conformity to experimental values over a wide range of 0.05 < Re < 300.