Tianyu Zhou, Zhihua Wang, Chao Ren,
Jiajun Zhang, Yongzhan He, Guofeng Chen, Pinyin Zhu,Yongzhong Zhu and Chao Liu
Baidu Inc., Beijing, China
IBM Poughkeepsie, NY. USA
The demand for compute capability is growing rapidly fueling the ever rising consumption of power by data centers the worldwide. This growth in power consumption presents a challenge to data center total cost of ownership. Free-air cooling is one of the industrial trends in reducing power consumption, the power usage effectiveness (PUE) ratio, and the total cost of ownership (TCO). Free-air cooling is a viable approach in many parts of the world where the air is reasonably clean. In Eastern China, the poor quality of air, high in particle and gaseous contamination, is a major obstacle to free-air cooling. Servers exposed to outside air blowing in to data centers will corrode and fail at high rate. The poor reliability of hardware increase TCO dramatically.
This paper describes a corrosion resistant server design suitable for reliable operation in a free-air cooling data center located in Eastern China where the indoor air quality can be as poor as ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) severity level G3. An accelerated corrosion test method of verifying hardware reliability in the ASHRAE severity level G3 environment is also described.
Reduction of TCO and PUE using free-air cooling is becoming an increasingly common practice in the USA and Europe and some other parts of the world where the outdoor air is relatively clean. Since the environment in Eastern China is much polluted to allow the straight forward use of free-air cooling, a more innovative approach involving the optimization of the IT equipment and the data center equipment design is needed. The IT equipment can be made robust against corrosive environments by conformally coating the corrosion-sensitive parts of the hardware. The improved IT equipment can be tested in an accelerated corrosion test, that has a copper corrosion rate of >800 2,tgo/c verify that the design improvements will result in 3-year plus reliable operation of the IT equipment in ISA 71.04-2013 severity level G3 environment.
Through additional research on the better understanding of the corrosion mechanisms in IT equipment, improved chemistries and means of applying conformal coating, accelerated corrosion testing of the improved designs and running the corrosion-resistant IT equipment in real-world polluted environments, it is hoped that we will be able to expand the use of free-air cooling in the polluted environments, even those with pollution levels as high as ISA 71.04-2013 severity level G3.
Initially Published in the IPC Proceedings