Reduced order thermal modeling of data centers via proper orthogonal decomposition: a review

Purpose - The purpose of this paper is to review the available reduced order modeling approaches in the literature for predicting the flow and specially temperature fields inside data centers in terms of the involved design parameters. Design/methodology/approach - This paper begins with a motivation for flow/thermal modeling needs for designing an energy-efficient thermal management system in data centers. Recent studies on air velocity and temperature field simulations in data centers through computational fluid dynamics/heat transfer (CFD/HT) are reviewed. Meta-modeling and reduced order modeling are tools to generate accurate and rapid surrogate models for a complex system. These tools, with a focus on low-dimensional models of turbulent flows are reviewed. Reduced order modeling techniques based on turbulent coherent structures identification, in particular the proper orthogonal decomposition (POD) are explained and reviewed in more details. Then, the available approaches for rapid thermal modeling of data centers are reviewed. Finally, recent studies on generating POD-based reduced order thermal models of data centers are reviewed and representative results are presented and compared for a case study. Findings - It is concluded that low-dimensional models are needed in order to predict the multi-parameter dependent thermal behavior of data centers accurately and rapidly for design and control purposes. POD-based techniques have shown great approximation for multi-parameter thermal modeling of data centers. It is believed that wavelet-based techniques due to the their ability to separate between coherent and incoherent structures something that POD cannot do can be considered as new promising tools for reduced order thermal modeling of complex electronic systems such as data centers Originality/value - The paper reviews different numerical methods and provides the reader with some insight for reduced order thermal modeling of complex convective systems such as data centers.