Local Cooling Control of Data Centers With Adaptive Vent Tiles

Abstract

Local airflow distribution in data center environments has historically been accomplished through ventilation tiles distributed over a raised floor air distribution plenum. The tiles are initially configured upon the commissioning of the facility and, as IT equipment configuration changes with time, the tiles are adjusted accordingly. However, tile adjustment is a manual process that is error-prone and often non-intuitive. Tile flow rates are a strong function of under floor plenum pressure distribution which is subject to change as tile layouts are reconfigured. Thermal models are often developed to assist with layout changes, but these models can be time-consuming to generate and require skilled users to achieve accurate results. This paper presents an adaptive vent tile (AVT) for use in raised floor data centers that can adapt to the needs of nearby IT equipment. We present a multi-input-multi-output (MIMO) AVT controller that automatically and dynamically adjusts a multiplicity of AVT openings in coordination such that thermal management requirements are met with minimum use of airflow. We describe the development of dynamic models and algorithm design of the MIMO controller. The controller was evaluated with a set of AVT units in a production data center environment. Results show that the controller can optimize local airflow distribution, provide fine-grained rack intake temperature control and respond to disturbances in a manner that is not achievable through static distribution of tiles.