An experimental study was conducted to investigate the effect of inclination angle on the pool boiling heat transfer of a stainless steel tube immersed in saturated water at atmospheric pressure. In this setup, the lower fluid inlet passage into the annular space was closed, and the annular space constituted 56% of the total heated length. The study found that increasing the inclination angle generally decreased the heat transfer coefficient. At an inclination angle of 95°, the critical heat flux was observed at 60kW/m². The formation of bubble clusters inside the annular space and the generation of pulsating flow were identified as the main mechanisms driving heat transfer. Based on the experimental data, a new correlation was developed to predict the heat transfer coefficient as a function of inclination angle and heat flux, with a predictive accuracy within ±5%.

pool boiling, annulus, inclination angles, heat exchanger design.

How to cite this article: Myeong-Gie Kang, Impact of inclination on pool boiling heat transfer on a partially annular tube with closed bottom inlet, JP Journal of Heat and Mass Transfer 38(2) (2025), 299-313. https://doi.org/10.17654/0973576325015

This Open Access Article is Licensed under Creative Commons Attribution 4.0 International License

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