Experimental Failure Analysis of a Rear Door Heat Exchanger With Localized Containment

The accelerated growth of heat load in high-density data centers presents challenges to the design of effective cooling solutions. Both energy efficiency and the information technology (IT) equipment reliability are key requirements. Localized hybrid air-water cooling systems such as Rear Door Heat eXchangers (RDHXs) are an effective means to achieve these requirements. In this paper, the transient aerodynamic and thermal performance of a commercial RDHX was investigated experimentally. The RDHX was attached to an isolated server cabinet with a controllable heat load. A localized containment system was used to direct the airflow to the equipment in the cabinet that emanates from a single perforated tile within the enclosure. The water flow rate and supply water temperature to the RDHX was controlled, and a grid of 36 air velocity/temperature sensors was employed to monitor the airside of the cooling system. The cooling performance of the RDHX in an air blower failure scenario was investigated. The failure scenario was designed to diminish different parts of the overall system. The impact on the IT equipment and the cabinet outlet temperatures was assessed. Also, there was a significant reduction in the airflow to the IT equipment. The impact of the reduced airflow on different parts of the cabinet as well as the cooling performance of the heat exchanger was characterized during both failure and recovery.