Numerical Simulation on Airflow in Plenum of
Underfloor Air Supply and Experiment on Characteristics of Plenum¡¯s Outlets
Kong Qiongxiang, Yu Bingfeng, Pan Zhen
(School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, China)
Abstract: 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-¦Å model and the grid size at
0ª±1m 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 170mm 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.
Keywords: underfloor air supply; plenum; computational fluid dynamics simulation; velocity
profiles of outlet