Current AM-TEC Research Projects
Energy Saving Potential of Low-Temperature Cooling of Computers
H. Ezzat Khalifa, Hamza Salih Erden, Romain B. de Rouge
Subzero Data Center Chip Cooling builds on the concept of powering and cooling data centers by on-site combined power and cooling (CPC) systems pioneered by Syracuse University (SU) and IBM and implemented in the first-of-its-kind system operating at the SU Green Data Center (GDC) since 2009. The current GDC operating regime is cooling computers with air at temperatures between 60 and 70 degrees Fahrenheit. This task will design a thermo-mechanical cascade system suitable for existing equipment in the SU GDC, creating a subzero cooling regime for computer chips. System performance will be modeled to determine overall energy savings (including energy required for cooling and reduced consumption by computer chips).
As of 2010, data centers (D/C) account for 2% of the total electricity consumption in US with a growth rate of 6% between 2005 and 2010. The rapidly escalating energy consumption of D/C has motivated the information technology (IT) industry and research institutions to seek solutions that substantially moderate this trend. Efforts on multiple fronts are underway including increased use of economizers, improved thermal management and liquid cooling technologies (e.g., liquid cooling), thermally-aware designs, on-site combined power and cooling, direct current (DC) power supply & distribution, and virtualization. Many of these efforts have focused on reducing the power consumption of the D/C cooling infrastructure, primarily by driving toward higher coolant temperature to reduce refrigeration power.
This has been accomplished by the Power and Refrigeration Cascade System (PARCS) to reduce energy consumption in Data Centers, evaluate potential for PARCS in multiple markets, and assess a way to integrate a PARCS demonstration within the existing Syracuse University Green Data Center (GDC) (See figures above). The goal of the PARCS system is to realize the benefits of low-temperature chip operation while decreasing the overall power consumption of servers and their cooling infrastructure. With the introduction of PARCS to data centers, one can expect ~40% reduction in primary energy used by these types of buildings.
Critical Height of Micro/Nano Structures for Pool Boiling Heat Transfer Enhancement
An Zou & Shalabh C. Maroo
Nanomaterials have shown great potential for improvements in thermal efficiency and materials use in Thermal and Environmental Controls (TECS) products. The successful development of large-scale, cost-effective fabrication technologies will open the market for dramatic reductions in size, materials, and energy use in heat exchangers and heat transfer equipment.
Boiling is widely used in domestic and industrial applications due to its ability to transfer large quantities of thermal energy across a small surface area. Applications range from residential refrigeration systems to boiling water reactors in power generation systems. Heat transfer via boiling has a fundamental limit known as the Critical Heat Flux (CHF). The limit is governed by the rate at which bubbles of gas, vaporized in the boiling process, can be removed from the heat transfer surface to allow subsequent fluid to boil. This project involves the fabrication of novel nanostructured surfaces and research into the scalability of these surfaces to large-area systems to increase the rate of heat transfer in the boiling processes. Variety of micro/nanostructures have been fabricated on plain surfaces, which have led to increase in the CHF limit. Specifically, fabrication of nano- wires and nanotubes, micro/nanoparticles deposition, regular micro/nanogeometries (pillars, fins, and micro- channels) have been done.
With the addition of these ridges, CHF increase of ~125% has been obtained with only ~40% increase in surface area, hence a greater efficiency in the boiling process (lower energy consumption).
For more information please refer to the full Applied Physics Letter which can be found here.
Project Focus Areas
TECS are highly engineered systems that monitor and control temperature and environmental quality in a wide range of applications, including: heating, ventilation, and air conditioning (HVAC) for buildings and vehicles; refrigeration for preserving and transporting produce; controlling temperature and air quality in clean rooms, data centers and within sensitive equipment; protecting patients and health-care providers via isolation and disinfection systems in hospitals; and controlling thermodynamic properties of gases, liquids, and solids in manufacturing processes. CNY firms and institutions have a long history of pioneering TECS innovations, including air conditioning systems, innovative boilers, cryogenic refrigeration, and combined cooling and power generation for data centers.