Extreme damping: Mechanics of the bottle flip challenge

Desired candidate : Master’s student.

The challenge consists in spinning a water bottle exactly one rotation before landing. While this is practically impossible for a completely filled or empty bottle, it is rather easy to complete the challenge with a partially filled bottle. The fluid redistribution increases the moment of inertia, and conservation of angular momentum implies a decrease of angular velocity. We can thus achieve to obtain a nearly vertical descent of the water bottle. The impact then releases all the kinetic energy into fluid motion (jet formation and sloshing), preventing the bottle from rebounding.

We will study in details the impact damping phase of the bottle flip challenge from the point of view of fluid mechanics, experimentally and theoretically. A numerical code previously developed in our laboratory will be adapted to include inertial forces. The project also includes the fabrication of a mechanical arm to control the initial conditions of the bottle, and map the probability of successful landings at increasing fluid filling. In addition, high speed photography and fluid-related imagery techniques (PIV) will be performed and compared to predictions to obtain valuable insights into the rich dynamics of this seemingly simple configuration.

Figure 1- Snapshots of a successful flipped water bottle. Reproduced from Pim Dekker, et al. “Water Bottle Flipping Physics.” arXiv preprint, arXiv:1712.08271 (2017).

Supervisor: Hervé Elettro