Unified Modeling Framework for Thin-Film Evaporation from Micropillar Arrays Capturing Local Interfacial Effects

Area of Science:

• Heat Transfer
• Fluid Dynamics
• Materials Science

Background:

• Micropillar array porous media are vital for energy conversion and electronics thermal management.
• Optimized flow and increased liquid-vapor interface area enhance phase-change heat transfer performance.

Purpose of the Study:

• Develop a unified semianalytical model to accurately predict dry-out heat flux in thin-film evaporation from micropillar arrays.
• Precisely predict pressure profiles and local permeability influenced by meniscus shape.

Main Methods:

• Discretized the porous media domain to determine pressure profiles.
• Incorporated local permeability dependent on meniscus shape.
• Validated permeability with 3D numerical simulations and the overall model with experimental data.

Main Results:

• The semianalytical model accurately predicts dry-out heat flux.
• Accurate prediction of liquid-vapor interface shape is critical for model accuracy.
• The model demonstrates a non-computational fluid dynamics (CFD) based approach.

Conclusions:

• The developed modeling framework offers accurate dry-out heat flux prediction for thin-film evaporation in micropillar arrays.
• This methodology is essential for optimizing devices in energy conversion and electronics cooling.
• It provides a general framework for modeling phase-change processes in porous media.