Structural optimization of deflector within air-water direct contact tank based on uniform design

Abstract

Abstract An appropriate microenvironment for preserving cultural relics is essential, and the air-water direct contact technology is utilized to create the microenvironment recently. The influence of a deflector in a tank was numerically investigated based on uniform design method to improve the heat and mass transfer and pressure drop performance of the air-water direct tank. In this study, a simplified CFD-based model was established and validated between airstream and water surface within the tank, to analyze the heat and mass transfer and pressure drop processes. Meanwhile, regression models of the heat transfers rate, mass transfer rate and pressure drop were developed by uniform design method based on three parameters: installation position, tilt angle, and height of the deflector, in order to analyze the influences of these three parameters on the heat and mass transfer and pressure drop of the tank. Finally, all three optimal structural parameters of the deflector were obtained based on the proposed comprehensive evaluation index using a genetic algorithm. The results showed that the model established for air-water direct contact adopted well to predict the heat and mass transfer and pressure drop performance between airstream and still water surface. Furthermore, the results found that the flow field inside the water tank was affected by the deflector s structure, which affected the heat and mass transfer performance. The simulation results suggested that the deflector s optimal structural parameters are 8\xa0mm of installation position, 88 ° of tilt angle and 19\xa0mm of height, respectively, within a given extent in this study.