Three‐Tier Hierarchical Structures for Extreme Pool Boiling Heat Transfer Performance
Abstract
Boiling is an effective energy‐transfer process with substantial utility in energy applications. Boiling performance is described mainly by the heat‐transfer coefficient (HTC) and critical heat flux (CHF). Recent efforts for the simultaneous enhancement of HTC and CHF have been limited by an intrinsic trade‐off between them—HTC enhancement requires high nucleation‐site density, which can increase bubble coalescence resulting in limited CHF enhancement. In this work, this trade‐off is overcome by designing three‐tier hierarchical structures. The bubble coalescence is minimized to enhance the CHF by defining nucleation sites with microcavities interspersed within hemi‐wicking structures. Meanwhile, the reduced nucleation‐site density is compensated for by incorporating nanostructures that promote evaporation for HTC enhancement. The hierarchical structures demonstrate the simultaneous enhancement of HTC and CHF up to 389% and 138%, respectively, compared to a smooth surface. This extreme boiling performance can lead to significant energy savings in a variety of boiling applications.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 12, 2022
- Source ID
- 10.1002/adma.202200899
Entities
People
- Carlos D. Díaz‐Marín
- Evelyn Wang
- Hyeongyun Cha
- Lenan Zhang
- Yajing Zhao
- Youngsup Song
Organizations
- Air Force Office of Scientific Research
- Defense Advanced Research Projects Agency
- Massachusetts Institute of Technology
- United States Department of Energy