Experimental Investigation Regarding Rack Pressure Resistance on Cooling Performance of a Container Data Center

This paper experimentally investigates the effect of pressure resistance distribution by using perforated grilles with different porosities (F=100%, 58% and 35.4%) in a container data center. The inlet and outlet temperature distribution, rack cooling index (RCI) and supply heat index (SHI) are used to evaluate the cooling performance under semi-contained and fully contained configurations. As a result, the airflow reversal phenomenon at the top cabinets is found, which is especially conspicuous for the case without perforated grilles due to the extremely low pressure resistance in the cabinet. By implementing perforated grilles at lower three cabinets, the airflow reversal can be eliminated, however, it cannot be completely removed. By applying perforated grilles with F=35.4% at the top three cabinets can increase the pressure resistance at the cabinets S1 where the airflow reversal is eliminated thoroughly. Yet, the performance of cabinets at rack A1 may degrade rapidly due to much stronger hot-exhaust recirculation. Hence, the fully contained configuration is applied. Note that the airflow reversal is more severe for the case without perforated grilles. By arranging the perforated grilles with F = 35.4%, the corresponding RCI and SHI may reach the ideal values of 100% and zero, respectively. Therefore, the perforated grilles with F = 35.4% are more reasonable for simulated racks under semi-contained and fully contained configurations when airflow reversal occurs.