The goal of air management system in high-density data centers is to minimize hot air re-circulation and cold air by-pass in data centers. If successfully implemented, both goals will result in energy savings and enhanced thermal conditions. Air management helps to reduce operating costs by enhancing economizer utilization and improving cooling system efficiency. Metrics play a significant role in providing performance indices, which include Supply/Return Heat Index (SHI/RHI), the rack cooling index (RCI) and the return temperature index (RTI), of air management systems. CFD simulation estimates temperature and airflow in the data center as well as to provide wealth of information to evaluate airflow performance. This study defines four performance metrics that analyzes air management systems. These metrics were computed with CFD modeling of 46 different design alternatives to evaluate the thermal environment in a typical data center module. Advanced and comprehensive evaluation index of cooling efficiency was also derived as well-crafted metrics will undoubtedly play an important role. (C) 2013 Elsevier B.V. All rights reserved.