Optimization on jet‐induced ventilation to enhance the uniformity of airflow distribution in data center

• Published in: Energy science & engineering 2021-11, Vol.9 (11), p.1973-1996
• Main Authors: Zhang, Zhe, Niu, Baolian, Zhang, Zhongbin, Shi, Min
• Format: Article
• Language: English
• Subjects: Air flow; air flow distribution; Air temperature; CFD investigations; Cold; Cold flow; Computer centers; Data centers; Efficiency; Energy consumption; Flow rates; Flow velocity; Heat; Heterogeneity; Horizontal orientation; jet‐induced ventilation system; Methods; Optimization; Overheating; Parameters; Pressure distribution; Racks; Thermal environments; Ventilation
• ISSN: 2050-0505; 2050-0505
• DOI: 10.1002/ese3.986

Improving the utilization efficiency of cold airflow in data center (DC) has already attracted widespread concern. A broad consensus has been reached that cold/hot‐aisle containment technologies can reduce the mixture of cold and hot air to weaken the overheating phenomenon of the rack in a certain extent. However, local hot spots still occur in the front racks due to lower tile flow rate at the entrance of the cold aisle, which means the thermal environment of front racks can be further improved to achieve the more uniform airflow distribution horizontally and vertically in DC. In this paper, an innovative method of airflow optimization applying jet fans in the cold aisles is proposed to make up the lower tile flow rate, adjust the flow path of cold air from the perforated tiles to racks, and balance temperature heterogeneity. In addition, inductive velocity, nozzle height, horizontal position, and attachment distance of jet fans are optimized to explore the optimal parameters. Results show that the incorporation of jet‐induced ventilation can effectively improve the cooling performance and overall thermal environment in DC, while the amount of IT equipment that exceeded the ASHRAE recommended supply air temperature (SAT) is reduced by about 38%. The jet fan with optimal parameters has a broad application space in the raised floor DC. In view of the airflow consistency and temperature uniformity have poor performance and the cabinets are overheating seriously in the raised‐floor data centers (DCs), this paper innovatively proposes a locally active optimization method and build a new concept of the coupling air supply system (CASS) with the incorporation of jet‐induced ventilation in the under‐floor air supply system (UASS) without changing the original air supply structure. In addition, numerical simulation and experimental verification are used to investigate the effect of inductive velocity, nozzle height, horizontal distance, and attachment distance on thermal performance of DC, so as to obtain the optimal parameters of jet fan. In general, the application of jet fans improves the utilization rate of cooling capacity, enhances the airflow distribution uniformity, and cooling performance in DC. It is hoped that this study can provide some reference for DC thermal performance optimization and energy saving in the future.