Performance Evaluation of An Innovative Column Attachment Ventilation

Xi’an University of Architecture and Technology, School of Building Services Science and Engineering, 710055, Xi’an, China

^* Corresponding author: liag@xauat.edu.cn

Abstract

An innovative column attachment ventilation (CAV) was proposed for heating, ventilating and air-conditioning (HVAC) systems and its performance was evaluated through experimental investigation and numerical modeling. Airflow pattern, air temperature distribution, air diffusion performance index (ADPI), predicted mean vote (PMV), and draught rate (DR), were used as the performance indicators to investigate the air distribution performance. The ventilation effectiveness for heat removal in the CAV mode was compared with a conventional mixing ventilation (MV). The results showed that the discharged air from the linear slot diffuser can attach to the column and enter into the occupied zone creating air lake phenomenon. The airflow spread over the floor in a radial pattern behaved as a stratified air distribution like displacement ventilation (DV), providing good air quality and comfort level for occupants. Moreover, the heat removal effectiveness in the CAV was found to be higher than in the MV, i.e. 1.32 in the C-CAV and 1.29 in the S-CAV modes. The column attachment ventilation can achieve thermal comfort in the occupied zone without local discomfort caused by high vertical temperature difference and draught, and this ventilation strategy could be expected as a new and efficient air distribution pattern for different HVAC applications.