TY - JOUR
TI - Effect of different heat exchange tube surface characteristics and microstructures on heat transfer performance
AU - Li Heng
AU - Ma Xiaojing
AU - Cao Jiamei
AU - Kari Tusongjiang
AU - Li Lin
AU - Meng Yifang
JN - Thermal Science
PY - 2025
VL - 29
IS - 3
SP - 2479
EP - 2489
PT - Article
AB - Falling film evaporation is an efficient phase-change heat transfer technology widely used in refrigeration and industrial applications. An experimental platform for horizontal tube falling film evaporation was designed and constructed. Exper¬iments were conducted on smooth tubes, T-shaped finned tubes, and finned tubes. The results show that the heat transfer performance of finned tubes is not as good as that of smooth tubes when the spray density, Г, is less than 0.048 kg/ms. When the tube diameter decreases, the heat transfer performance of finned tubes exceeds that of smooth tubes at approximately Г = 0.032 kg/ms. However, the heat transfer performance of T-shaped finned tubes has consistently been superior to that of smooth tubes. After hydrophilic coating treatment, the heat transfer performance of T-shaped finned tubes and smooth tubes initially increased, then decreased, and eventually stabilized as spray density increased. At a saturation temperature, Tsat, of 70°C and Г = 0.0087 kg/ms, the heat transfer coefficient decreases due to deterioration on the tube surface. Under identical experimental conditions, the heat transfer performance of the T-shaped finned tube and the finned tube improved by approximately 56%-62% and 28%-35%, respectively, compared with the smooth tube. Hydrophilically modified smooth, T-shaped finned, and finned tubes improved heat transfer coefficients by approximately 51%, 45%, and 11%, respectively. Overall, the T-shaped finned tube demonstrated superior performance compared to other tubes under all tested conditions, making it a promising choice for enhanced heat transfer applications.