Physics-Based Modeling and Measurement of High-Flux Condensation Heat Transfer

This report examines condensation of FC-72 along parallel, square micro-channels with a hydraulic diameter of 1 mm and a length of 29.9 cm, which are formed in the top surface of a solid copper plate. Using high-speed video imaging and photomicrographic techniques, five distinct flow regimes are identified smooth-annular, wavy-annular, transition, slug, and bubbly, with the smooth-annular and wavy-annular regimes being most prevalent. A theoretical control-volume-based model is proposed based on the assumptions of smooth interface between the annular liquid film and vapor core, and uniform film thickness around the channels circumference. The new model accurately captures the pressure drop and heat transfer coefficient data in both magnitude and trend, evidenced by mean absolute error values of 3.6 and 9.3, respectively.