All changes within the data center environment should be modeled prior to resources being committed to their implementation, even if they have commonly accepted wisdom at their heart. Changing any aspect of a data center that impacts the flow of air within the room will change the thermal performance of the entire facility. Without modeling and simulation it is impossible to accurately determine this impact in advance.
Changes to the airflow pattern within the data center can create hotspots, now and/or in the future regardless of what kind of change is made.
Changes in airflow through the grilles in the facility from ‘An Energy Efficiency Drive That Can Cost More Than It Saves’ by David King
In the drive for efficiency, many data center operators are upgrading the old fans in their cooling units to modern energy efficient versions. However, the impact on the air flow within the facility is very rarely considered when planning such an upgrade. In his recent white-paper ‘An energy efficiency drive that can cost more than it saves’, David King investigates the full implications of such a change on air flow and therefore the cooling available to the IT equipment . The white-paper demonstrates that the changes could impact the IT equipment in a way such that the costs vastly outweigh the savings in energy. He argues that in order to accurately assess the impact of any changes and perform a proper cost/benefit analysis, they need to be fully modeled first. The example is built around changing cooling unit fans and models the implications of three different types of fans.
If you model the changes in the Data Center in advance of making a financial commitment it is possible to determine ahead of your spend if you can generate a positive return on your investment (or conversely if making the change will create other secondary problems to be solved and that money will need to be spent on).
Data Center Infrastructure & Critical Facility Evolution 