Numerical simulation on airflow in plenum of underfloor air supply and experiment on characteristics of plenum's outlets

The airflow in a plenum of underfloor air supply was simulated by computational fluid dynamics (CFD) program, and full-scale experiments were conducted to validate the calculation results. The standard k-Ε model and the grid size at 0.1 m were used in the CFD program. The results show that the predicted velocity profiles of outlets in the plenum were in good agreement with the measured velocity profiles. Moreover, with the plenum in 170 mm height, the velocity profiles of outlets and their air flow ratio were influenced by inlet jet. In addition, according to outlet's location on the underfloor, some of the velocity profiles of outlets were uniform, and some were not as the smallest velocity was 10% of the biggest velocity in an outlet. The above characteristics of the plenum's outlets could be analyzed by the plenum airflow patterns obtained from CFD simulation.