Thermal design methodology for electronic systems

This paper presents the thermal design methodology used to design a multi-processor enterprise server, the RP8400. The proposed methodology combines well-known analytical and experimental thermal design tools, including heat transfer correlations, Flow Network Modeling (FNM) and Computational Fluid Dynamics (CFD) techniques, and experimental measurements. The key benefit of this methodology is its emphasis on the use of varied design tools, each applied at its optimal point in the product design cycle. Thus, analysis time is greatly reduced, with acceptable sacrifice to accuracy and detail, during the earliest stages of design when the design concept is fluid, new ideas abound, and speed is paramount. Detailed analyses, providing a greater degree of accuracy, are performed in the latter stages of the development cycle when designs are firm, changes are fewer, and optimization/validation is the goal. In this manner, thermal risk is systematically reduced throughout the product design cycle. This paper begins with an overview of the thermal design methodology. Direct application of the methodology to the design of an enterprise server, the RP8400, is discussed. Numerical modeling and empirical results are presented and compared, followed by a discussion of methods for improving thermal design in future products.