Library Subscription: Guest
Home Begell Digital Library eBooks Journals References & Proceedings Research Collections
Journal of Enhanced Heat Transfer

Impact factor: 0.400

ISSN Print: 1065-5131
ISSN Online: 1563-5074

Journal of Enhanced Heat Transfer

DOI: 10.1615/JEnhHeatTransf.v18.i1.20
pages 15-30

ENERGY EFFICIENT THERMAL MANAGEMENT OF DATA CENTERS VIA OPEN MULTI-SCALE DESIGN: A REVIEW OF RESEARCH QUESTIONS AND APPROACHES

Yogendra Joshi
G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
Emad Samadiani
G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA

ABSTRACT

Currently, the airflow and heat transfer characteristics of data centers are simulated through computational fluid dynamics and heat transfer (CFD/HT) modeling. The degrees of freedom of these models are too large to be efficiently used with methodologies for effective design around the significant parameters of interest. Effective modeling and design of a data center is complicated due to its multi-scale nature, where length scales span four orders of magnitude from the room and plenum to the rack, to the server, and to the chip levels. Multi-scale resolution in simulation and design methodologies is important because the system design objectives (e.g., keeping the chip temperature in a desirable range) and the heat generation sources are located at the chip scale, yet the design solution (cold air from cooling units) spans the plenum and room scales. Using a complete CFD/HT model involving all of these length scales is infeasible for design. This paper begins with a review of the recent studies on energy usage trends and the need for energy efficient thermal management of data centers. Reduced order modeling of the thermal/fluid phenomena, by coupling the transport at different scales of the data center, is reviewed as a method that can be easily incorporated in design methodologies to find the optimum design variables involved at all scales. The energy-efficient design of data centers is a multi-objective problem. This design problem and possible multi-objective methodologies are reviewed. Incorporation of the coupled multi-scale model within established multi-objective design frameworks potentially allows for energy efficient open or scalable design of new facilities as well as retro-fits of current ones. These concepts are illustrated with selected examples.