Ellipsoidal fluid particles

The conditions under which fluid particles adopt an ellipsoidal shape are outlined in Chapter 2 (see Fig. 2.5). In most systems, bubbles and drops in the intermediate size range d typically between 1 and 15 mm) lie in this regime. However, bubbles and drops in systems of high Morton number are never ellipsoidal. Ellipsoidal fluid particles can often be approximated as oblate spheroids with vertical axes of symmetry, but this approximation is not always reliable. Bubbles and drops in this regime often lack fore-and-aft symmetry, and show shape oscillations. 

The book by Clift, Grace, and Weber, Bubbles, Drops and Particles (ibid.) devotes its Chapter 7 to the dynamics of ellipsoidal fluid particles. This book is a major reference on the topic of fluid particles. 

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