CFD Optimization of the cooling of Yosemite Open Compute Server

Rising energy demands in data centers have constantly made thermal engineers to think and come up with innovative cooling solutions in data centers. It is of utmost importance to have control over the environmental impact of Data Centers. In 2011, the Open Compute Project was started which aimed at sharing energy efficient practices for data centers. The hardware and electrical specifications of the first open compute server – Freedom was shared on open compute project’s website. It was a vanity free design and its components were custom designed. It was deployed in one of the data centers in Prineville, Oregon and within first few months of operation, considerable savings in every and cost were observed. Since then, many open compute servers have been introduced for applications like – compute, storage, etc. The open compute servers which were being introduced mainly had a 2 socket architecture. Yosemite Open compute server was introduced for serving heavy compute workloads. It provided significant improvement in performance per watt as compared to previous generations open compute servers. Yosemite Open Compute Server has a system on a chip architecture and has 4 CPU’s (1 CPU per sled). This study involves optimization of Yosemite Open Compute server to improve its cooling performance using. CFD tools are very useful for thermal modeling of these servers and predict their efficiency. A commercially available CFD tool has been used to do the thermal modeling of the server and its optimization has been done to improve the cooling performance of the server. The model of the improved design has been compared to the existing design to show the impact of air flow optimization on the cooling performance of the server. The air flow characteristics and utilization of the fans have been significantly improved in the improved design.