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Abstract Demand is growing for the dense and high-performing IT computing capacity to support artificial intelligence, deep learning, machine learning, autonomous cars, the Internet of Things, etc. This led to an unprecedented growth in transistor density for high-end CPUs and GPUs, creating thermal design power (TDP) of even more than 700 watts for some of the NVIDIA existing GPUs. Cooling these high TDP chips with air cooling comes with a cost of the higher form factor of servers and noise produced by server fans close to the permissible limit. Direct-to-chip cold plate-based liquid cooling is highly efficient and becoming more reliable as the advancement in technology is taking place. Several components are used in the liquid-cooled data centers for the deployment of cold plate-based direct-to-chip liquid cooling like cooling loops, rack manifolds, CDUs, row manifolds, quick disconnects, flow control valves, etc. Row manifolds used in liquid cooling are used to distribute secondary coolant to the rack manifolds. Characterizing these row manifolds to understand the pressure drops and flow distribution for better data center design and energy efficiency is important. In this paper, the methodology is developed to characterize the row manifolds. Water-based coolant Propylene glycol 25% was used as the coolant for the experiments and experiments were conducted at 21 °C coolant supply temperature. Two, six-port row manifolds' P-Q curves were generated, and the value of supply pressure and the flowrate were measured at each port. The results obtained from the experiments were validated by a technique called flow network modeling (FNM). FNM technique uses the overall flow and thermal characteristics to represent the behavior of individual components.
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A Novel Thermal Mapping Technique using Nano-confinement Assisted Quantum Dots for Transient Cooling Applications
During air or liquid cooling, thermal resistance of the devices is measured precisely from the thermal information at the junction. But existing thermal measurement technologies fall short because of highly transient events such as unstable vortex formation (air cooling) and bubble growth (two-phase liquid cooling). In solving this problem, this paper reports a novel and low-cost thermal mapping technique that can capture highly spatio-temporal temperature evolution at the solid-liquid interface. Essentially, a robust interface is fabricated with CuInS 2 /ZnS Quantum dots (λ peak = 550 nm and 750 nm) trapped inside nanopores (20 nm-30 nm) of a ceramic membrane (50 μm) and/or everyday use paper. It is observed that such nanoconfinement assisted Quantum dots provided sustained thermal photoluminescence coefficient (-0.1 nm/°C) at high number of heating-cooling cycle. This unique yet low cost thermal mapping technique is applied to capture thermal evolution during micro-droplet impingement cooling and hemiwicking flows through anisotropic wicks which showcase commendable spatio-temporal benefits.
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- Award ID(s):
- 1653396
- PAR ID:
- 10433046
- Date Published:
- Journal Name:
- 2020 19th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm)
- Page Range / eLocation ID:
- 926 to 931
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/ITherm45881.2020.9190349
