title: Steady State Vapor Bubble in Pool Boiling.
abstract: Boiling, a dynamic and multiscale process, has been studied for several decades; however, a comprehensive understanding of the process is still lacking. The bubble ebullition cycle, which occurs over millisecond time-span, makes it extremely challenging to study near-surface interfacial characteristics of a single bubble. Here, we create a steady-state vapor bubble that can remain stable for hours in a pool of sub-cooled water using a femtosecond laser source. The stability of the bubble allows us to measure the contact-angle and perform in-situ imaging of the contact-line region and the microlayer, on hydrophilic and hydrophobic surfaces and in both degassed and regular (with dissolved air) water. The early growth stage of vapor bubble in degassed water shows a completely wetted bubble base with the microlayer, and the bubble does not depart from the surface due to reduced liquid pressure in the microlayer. Using experimental data and numerical simulations, we obtain permissible range of maximum heat transfer coefficient possible in nucleate boiling and the width of the evaporating layer in the contact-line region. This technique of creating and measuring fundamental characteristics of a stable vapor bubble will facilitate rational design of nanostructures for boiling enhancement and advance thermal management in electronics.
authors.affiliation: Department of Mechanical &Aerospace Engineering, Syracuse University, Syracuse NY 13244 USA.
authors.forename: An
authors.initials: A
authors.lastname: Zou
authors.affiliation: Department of Electrical Engineering and Computer Science, Syracuse University, Syracuse NY 13244 USA.
authors.forename: Ashish
authors.initials: A
authors.lastname: Chanana
authors.affiliation: Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg MD 20899 USA.|Maryland Nanocenter, University of Maryland, College Park MD 20742 USA.
authors.forename: Amit
authors.initials: A
authors.lastname: Agrawal
authors.affiliation: Department of Chemical &Biological Engineering, Rensselaer Polytechnic Institute, Troy NY 12180 USA.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Wayner
authors.affiliation: Department of Mechanical &Aerospace Engineering, Syracuse University, Syracuse NY 13244 USA.
authors.forename: Shalabh C
authors.initials: SC
authors.lastname: Maroo
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