EAGER: Pool Boiling of Water on a Binary Surface

New Mexico State University, Las Cruces NM

Investigators

Abstract

Boiling of water to transfer heat has applications in our day-to-day lives, e.g., in power generation, water purification, and cooking. When water boils over a surface, substantial amounts of heat can be transferred from the surface to the water without causing a significant increase in the surface temperature; hence, boiling is also used in applications such as cooling of electronics where large temperature rises are prohibitive. However, when a large amount of heat must be removed from a small area through boiling, it encounters a crisis called the Critical Heat Flux (CHF) limit. At this limit, the rapidly generated vapor bubbles merge to form a vapor film on the hot surface which prevents liquid water to contact the surface. This project pursues a new type of surface, called the Binary Surface(s) (BiS), for extending the current CHF limits for the boiling of water. The underlying science that enables enhanced boiling performance of water on BiS will be shared with the public through YouTube videos. A BiS is a highly wetting surface with many sub-surface micro-/nano-cavities, which are filled with a Non-Boiling Liquid (NBL) creating puddles around solid islands. The goal of this research project is two-fold: (1) to experimentally measure the CHF and the Heat Transfer Coefficient for the pool boiling of water on a copper-oil BiS (oil is the NBL) and compare them with those obtained on hydrophilic and hydrophobic surfaces and (2) to obtain evidence for the hypothesis that heterogeneous bubble nucleation occurs on a BiS. Two tasks are planned to realize this goal and they include pool boiling experiments and BiS surface preparation and analysis before and after the experiments. This project helps to establish the feasibility of a new boiling enhancement mechanism that could have a significant impact in many fields. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.