System-level thermal management modeling of a supercomputer chassis

In this paper, the thermal performance of a 4U drawer-type chassis being used in the cabinet of a kind of supercomputer system was simulated so as to evaluate and optimize the primary design and subsequently arrange for mock-up. This study focuses on the 128 ASIC chips, which generate approximately 700 watts of power. This study described the process of using the FLOTHERM simulation software to evaluate the pressure, velocity of airflow and the temperature distribution especially maximum chip temperature in chassis. In this modeling three-dimensional, steady state and forced wind cooling is assumed. The rigorous three-dimensional finite element thermal model is established. The significant variables of the chassis, such as the layout of PCB, parameters of heatsink and fans, clearance spacing between PCBs, chip power dissipation, ambient temperature and air refrigeration mode etc. are analyzed and optimized. The dependency relationship of maximum chip temperature vs. fin-pitch, fin-thickness and clearance space between PCBs are given quantitatively and qualitatively, respectively. The actual chassis mock-up in accordance with the optimized result is in process.