Turning Drops into Bubbles: Cavitation by Vapor Diffusion through Elastic Networks.

Area of Science:

• Physics
• Materials Science
• Biophysics

Background:

• Some plants exhibit rapid movements driven by physical processes.
• These movements involve a complex interplay of evaporation, elasticity, and cavitation.
• Understanding the energy transformation in these biological systems is key.

Purpose of the Study:

• To investigate the physics behind rapid movement in plants.
• To model the energy transformation from enthalpic to elastic to kinetic energy.
• To explore a model system for synthetic motile materials.

Main Methods:

• Experimental study of a droplet in an elastic medium.
• Observation of slow diffusion-driven shrinkage.
• Analysis of rapid cavitation events and bubble dynamics.
• Modeling using classical diffusion and inertial-(visco)elastic models.

Main Results:

• Observed cavity dynamics across 9 orders of magnitude in timescale.
• Validated a model combining diffusion for shrinkage and inertial-(visco)elasticity for cavitation.
• Demonstrated excellent agreement between experimental data and the model.

Conclusions:

• The model system effectively replicates the energy transformation seen in plants.
• The developed model accurately describes the disparate timescales involved.
• This research provides a new paradigm for designing synthetic motile materials.