boildry

Boildry is a term used in speculative discussions to describe a process where a liquid in contact with a porous solid experiences vigorous boiling that is coupled with rapid drying of the surrounding matrix. The word is a combination of boil and dry, and has appeared in theoretical notes and some experimental reports as a way to describe competing mass-transport processes in porous media.

Mechanism: When heat is applied to a liquid in a porous substrate, nucleate boiling can create vapor that migrates through pores. If the evaporation rate at the liquid–solid interface exceeds capillary replenishment and vapor removal, a dry crust forms at the surface while liquid remains beneath the crust. The transition between boiling regimes and the geometry of the pores influence the pattern of drying and crust formation.

Observations and measurement: boildry can be studied with thermography, high-speed imaging, gravimetric analysis, and imaging techniques like X-ray or MRI to track liquid distribution. Researchers distinguish boildry from simple boiling with surface drying by observing simultaneous surface crust formation and sub-surface liquid retention.

Applications and significance: though largely conceptual, boildry has been discussed in contexts such as drying of porous ceramics, advanced manufacturing, and food-processing scenarios where control of surface dryness and internal moisture is important. It highlights the coupling of phase change with transport in porous media and the challenges in modeling such systems.

See also boiling, drying, porous media, evaporation, crust formation, and drying kinetics.