Boiling heat transfer enhancement of submerged water jet impingement on wick structures

Abstract

Click on the DOI link to access this article at the publishers website (may not be free).In this study, the boiling heat transfer characteristics of a submerged water jet impingement on a plain surface, a monolayer wick, and a columnar post wick were experimentally investigated. The effects of Reynolds numbers of 0, 846, 1270, and 1693 on the critical heat flux (CHF) were evaluated for the three different impinged surfaces. The wicks were fabricated using a multi-step sintering process with 200 μm copper particles, and boiling experiments were conducted using water at ambient pressure. The results show significant increases in CHF when monolayer and columnar post wicks were used in the boiling setup. This improvement is attributed to the reduced hydrodynamic instability wavelength, which decreased vapor generation and delayed surface dry-out. CHF enhancements were further amplified by employing an impinging jet. An important new finding in this study is that when the impinging jet is injected into the porous medium surface where boiling occurs, the CHF increases. Compared with the full boiling experiment, the CHF for the flat surface, single layer wick, and columnar post wick are 323.1%, 244.3%, and 266.6%, respectively. The wick and jet impingement design provides fundamental insights into simultaneous CHF enhancements, offering potential applications in advanced thermal management systems. © 2025 Taylor & Francis Group, LLC