Transient computational fluid dynamics-based optimization of radiant cooling ceiling integrated with wall-attached jet: Targeting condensation control

Based on a validated numerical model with a prediction error of <5%, this study investigated the condensation characteristics of a radiant cooling ceiling integrated with a wall-attached jet through transient computational fluid dynamics simulations. Research indicates that the areas comprising 25% of the radiant cooling ceiling near the outlet side were identified as high-risk condensation areas. On this basis, numerical calculations were conducted to investigate the effects of jet velocity, jet temperature, and initial indoor temperature on condensation risk, the indoor thermal environment, and the time required to achieve a comfortable environment. For every 0.2 m/s increase in jet velocity, the minimum temperature in this area rises by 0.49 °C, shortening the time to achieve thermal comfort by 105 s. At a jet velocity of 1.6 m/s, the minimum temperature remains over 1 °C above the dew point, eliminating condensation risk. At this velocity, every 2 °C decrease in jet temperature reduces the comfort attainment time by 120 s, while every 1 °C increase in initial indoor temperature extends it by 90 s. The recommended parameters are 1.6 m/s and 22C, effectively meeting cooling demands, ensuring thermal comfort, and reducing energy consumption.