# Optimization of Airflow Organization in Bidirectional Air Supply Data Centers in China
## 1 Introduction
[PERSON] advanced this approach by creating active perforated floors with auxiliary fans that adjust airflow through variable fan speeds, enabling precise cooling distribution that improves server inlet temperature uniformity [22]. However, subsequent research has shown that the additional energy consumption from these active systems may outweigh the energy savings from chillers, while potentially creating vortices in upper rack regions that exacerbate hotspot formation [23]. Containment solutions, including cold aisle enclosure [24], rack airflow guides, and blanking panels [25], have proven effective in reducing airflow losses and optimizing temperature distribution. [PERSON]'s comprehensive testing demonstrated that side containment provides superior temperature uniformity under adequate airflow conditions, though partial containment performs worse than open configurations during airflowshortages [26]. [PERSON]'s investigation of adjustable flexible baffles installed on rack doors and server exhaust areas confirmed their effectiveness in improving airflow distribution and reducing hotspot temperatures [27; 28]. However, the implementation of airflow guides often compromises data center aesthetics and occupies valuable rack space needed for cabling, making blanking panels in unoccupied rack spaces the more widely adopted solution in practice [11]. Numerous studies have been conducted to optimize data center airflow and improve thermal environments through experimental testing and numerical simulations. However, most research has focused on single optimization strategies, while combined approaches have received less attention. In operational scenarios, the thermal environment is influenced by multiple factors, including room layout, air conditioning air-flow patterns, server distribution, and heat density. To maintain continuous and stable operation, certain optimization methods prove difficult to implement, such as cooling system modifications or air conditioner layout adjustments. Therefore, ongoing research is still required for thermal environment optimization in existing data centers. A bidirectional airflow server room located in a hot-summer/warm-winter climate zone was selected for investigation in this study. CFD numerical simulations were combined with field measurements to establish a computational model based on actual heat load distributions. The thermal effects of rack blanking panels and cold aisle containment were systematically examined, including both individual implementations and combined strategies. This analysis was conducted to mitigate potential hotspot formation that could compromise equipment reliability. The obtained results provide operational optimization references for energy efficiency improvements in existing data center facilities. This paper is organized as follows. In Section 2, the data center configuration and experimental methodology are described, with the numerical modeling approach being presented in detail. In Section 3, the numerical model is validated through field measurements, with the existing thermal conditions being completely characterized. In Section 4, optimization strategies are developed, and thermal performance improvements for each design scenario are systematically analyzed. The main research conclusions are summarized in Section 5.