Floating Granite Sphere at CU Boulder | Flow Visualization | Get Wet Assignment 1 | 2024

This video showcases the iconic floating granite sphere situated in the courtyard of the Engineering Center in front of the DLC building at the University of Colorado Boulder. Captured and edited by Dron Das Purkayastha as part of an assignment for the Flow Visualization class (MCEN 5151) at the Paul M. Rady Department of Mechanical Engineering, University of Colorado Boulder.

The video was shot using a Canon M50 Mark I paired with a Canon EF 50mm STM prime lens. Filmed at 120 FPS in 720p (8-bit), the slow-motion footage highlights the sphere’s intricate motion and flow patterns. The horizontal width of the sphere in the frame measures 10 cm.

Aperture F10
Shutter !/160
ISO 200

Video link https://vimeo.com/1008666657

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Dyed water injected into dyed corn syrup displays the Saffman-Taylor fingering instability in a Hele-Shaw cell.

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Aluminum flakes in a pool of silicone oil heated from below displays the Bénard-Marangoni convection instability.

Aluminum flakes in a pool of silicone oil heated from below displays the Bénard-Marangoni convection instability. The resemblance to the Sun was achieved with post-processing of color.

Water droplets at the center of a heated pan exhibit the Leidenfrost effect, where film boiling insulates the droplet. Away from the hottest center, droplets evaporate quickly.

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