Development and Experimental Validation of an Integrated Evaporative and Hybrid Air-Liquid Cooling System for Intelligent Computing Centers

To address the heat dissipation challenges associated with high power density in intelligent computing centers， this study proposes an air-liquid dual source cooling system. The system utilizes a unified cold source with a stepwise water flow sequence of "air-cooling first， liquid-cooling second" to reduce exergy loss and match the temperature-grade of the respective cold source. The internal flow channel of the cooling unit was optimized through computational fluid dynamics simulations， and its performance was experimentally tested under high-temperature with high-humidity， moderate-temperature with moderate-humidity， and low-temperature conditions. Results indicate that the optimized unit achieves an outlet water temperature as low as 32.17 ℃ with a maximum coefficient of performance （COP） of 28.03 under high-temperature conditions. The unit also enables complete natural cooling under moderate conditions and reaches a peak COP of 33.4 under low-temperature conditions while maintaining stable operation. The system's overall approach degree ranges from 0.1 ℃ to 1.8 ℃， and its cooling capacity reaches 105.3%， outperforming the national standard. This study provides an efficient and practical cooling solution for high-density intelligent computing centers.