Direct evaporative cooling is widely used in data centers but risks elevating humidity. This study proposes a direct ventilation channel system integrating direct evaporative cooling with phase change plates. Experiments investigated effects of inlet air temperature (IAT: 28–44 °C), inlet relative humidity (IRH: 20–60%), air supply velocity (ASV: 1.0–3.0 m/s), and water flow (40–120 mL/min). Results show: (Ⅰ) The coupled system exhibits synergistic effects, achieving 31.43% cooling efficiency improvement as IAT increases from 28 °C to 44 °C. (Ⅱ) At IAT=36 °C and IRH=60%, outlet temperature reaches 27 °C with 62.3% RH, achieving 22% dehumidification rate. Dehumidification efficiency exceeds 18.8% for over 5 hours when IRH≥40%. (Ⅲ) Cooling performance factors order: IAT > ASV > IRH > WF, with IAT contributing 94.6%. Dehumidification factors order: IRH > IAT > ASV > WF, with IRH contributing 62.8% and IAT 23.9%. The system achieves EER up to 6.3 when meeting data center cooling demand (1728–3456 m 3 /h) at 30–32 °C. This study provides a feasible energy-saving cooling strategy for data centers.
Zhang et al. (Sun,) studied this question.