TY - JOUR

T1 - Capillary Wicking and Heat Transfer during Boiling of HFE-7100 on Black Silicon Surfaces with Different Morphologies

AU - Volodin, O.

AU - Vyacheslavova, E.

AU - Baranov, A.

AU - Malakhov, I.

AU - Konev, S.

AU - Kosovskikh, I.

AU - Serdyukov, V.

N1 - Volodin, O., Vyacheslavova, E., Baranov, A. et al. Capillary Wicking and Heat Transfer during Boiling of HFE-7100 on Black Silicon Surfaces with Different Morphologies. J. Engin. Thermophys. 34, 709–720 (2025). This work was supported by the Russian Science Foundation (project no. 23-29-10092) and the Government of the Novosibirsk oblast (agreement no. R-48). Part of the work related to the development and calibration of the experimental techniques (boiling facility, visualization and IR thermography methods, as well as SEM analysis of the fabricated surfaces) was carried out within the framework of the State Contract with the Kutateladze Institute of Thermophysics, Siberian Branch, Russian Academy of Sciences (project no. 121031800216-1).

PY - 2025/12

Y1 - 2025/12

N2 - The paper presents the results of an experimental study on the effect of the morphology of a hemi-wicking black silicon surface on capillary wicking and heat transfer characteristics during pool boiling of HFE-7100. The investigated homogeneous and hybrid silicon surfaces were fabricated using low-temperature plasma-chemical etching. It was shown that the modified silicon surfaces enhance liquid wicking, with taller homogeneous needle-like microstructures promoting more efficient liquid spreading. Hybrid surfaces (combining low and high needle-like microstructures) exhibit significantly higher values of the Wi number (characterizing capillary wicking) compared to homogeneous ones. Heat transfer experiments were carried out on the most efficient (in terms of capillary wicking) homogeneous and hybrid black silicon surfaces. Unlike in the case of water boiling, the expected increase in critical heat flux (CHF) was not achieved for HFE-7100 on black silicon surfaces due to the partial or complete loss of hydrophilicity during boiling. Instead, the experiments revealed a noticeable enhancement of the heat transfer coefficient (HTC) on both homogeneous and hybrid surfaces, which can be attributed exclusively to the effect of microstructuring rather than capillary wicking.

AB - The paper presents the results of an experimental study on the effect of the morphology of a hemi-wicking black silicon surface on capillary wicking and heat transfer characteristics during pool boiling of HFE-7100. The investigated homogeneous and hybrid silicon surfaces were fabricated using low-temperature plasma-chemical etching. It was shown that the modified silicon surfaces enhance liquid wicking, with taller homogeneous needle-like microstructures promoting more efficient liquid spreading. Hybrid surfaces (combining low and high needle-like microstructures) exhibit significantly higher values of the Wi number (characterizing capillary wicking) compared to homogeneous ones. Heat transfer experiments were carried out on the most efficient (in terms of capillary wicking) homogeneous and hybrid black silicon surfaces. Unlike in the case of water boiling, the expected increase in critical heat flux (CHF) was not achieved for HFE-7100 on black silicon surfaces due to the partial or complete loss of hydrophilicity during boiling. Instead, the experiments revealed a noticeable enhancement of the heat transfer coefficient (HTC) on both homogeneous and hybrid surfaces, which can be attributed exclusively to the effect of microstructuring rather than capillary wicking.

KW - CHF enhancement

KW - black silicon

KW - boiling

KW - bubble dynamics

KW - capillary wicking

KW - heat transfer enhancement

KW - plasma chemical etching

KW - superhydrophilic surface

UR - https://www.scopus.com/pages/publications/105035387286

UR - https://www.mendeley.com/catalogue/f865c993-8f66-35ed-9def-0b7b0e3cb60b/

U2 - 10.1134/S1810232825700225

DO - 10.1134/S1810232825700225

M3 - Article

VL - 34

SP - 709

EP - 720

JO - Journal of Engineering Thermophysics

JF - Journal of Engineering Thermophysics

SN - 1810-2328

IS - 4

ER -