Authors

Modelling film condensation using the volume fraction method: optimising heat transfer in compact channels

DOI: 10.17586/1606-4313-2026-25-1-74-81
UDC 621.43.016

Modelling film condensation using the volume fraction method: optimising heat transfer in compact channels

Alkhateeb Diaa , Lyulin Yuriy V.

For citation: Alkhateeb D., Lyulin Yu.V. Modelling film condensation using the volume fraction method: optimising heat transfer in compact channels. Journal of International Academy of Refrigeration. 2026. No 1. p. 74-81. DOI: 10.17586/1606-4313-2026-25-1-74-81. (in Russian)

Abstract
Film condensation in mini- and microchannels is a critical process in modern compact and high-efficiency heat transfer systems. This study presents a numerical analysis of the effects of temperature difference ΔT, vapor composition x, channel inclination and rotation angles, and aspect ratio (AR) on local film thickness δ, heat transfer coefficient (HTC), and pressure drop Δp. The results indicate that the effect of ΔT on δis non-linear: at low ΔT the film remains thin due to weak condensation, while at higher ΔT the film thickens due to intensified condensate formation. Optimal conditions at ΔT ≈ 10 K yield minimal film thickness δ≈ 18–22 μm and maximum HTC up to 13,800 W/m²·K. Inclination angles of 30-45° provide a balance between maintaining optimal film thickness and controlling hydraulic resistance. An aspect ratio AR = 2.0 delivers the highest heat transfer efficiency with moderate pressure losses. The novelty of this work lies in the quantitative integration of geometrical and operational parameters, enabling optimized design of mini- and microchannel heat exchangers.

Keywords: film condensation; mini-channels; VOF modelling; channel geometry; film thickness; heat transfer.

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