Graphics sure has evolved over the last two decades. From 8-bit resolution, pixels, and bitmaps, we now have 4K HDR and 1080p resolution. This has made our gaming experiences more immersive and ultra-realistic.

For these great graphics and experiences, GPUs (Graphic Processing Units) play an important role. Nowadays, they find use not only in gaming, but also in machine learning, content creation, video-editing, and even in training neural networks. The possibilities seem to be endless!

One of the main aspects one looks for in good GPUs, especially in gaming, is the heating aspect of the GPU. You don’t want a GPU that heats up a lot as this will affect the performance of the device.

Now imagine numerous GPUs along with CPUs (Central Processing Units), and other electronic components stored in a closed facility for an office or an organization. Imagine the amount of heat dissipated.

Such a place, in a building, or buildings to house computer systems and associated components is called a data center. Heating is a major issue in such places.

In order to cool such systems, 40 percent of the total electricity used goes into its operation. Thus there is a need to enhance the cooling system’s efficiency to save energy.

There are 3 ways a data center can be cooled. These are: room-level cooling, rack-level cooling, and chip-level cooling. Of these, chip-level cooling is preferred as it is more efficient compared to the other two, and the heat dissipation path is shortened.

It is preferred to cool the chips indirectly with cooling devices as it is promising and cost-effective. This is done through phase-change heat transfer devices such as heat pipes or thermosyphons. The thermosyphon transports heat passively, and without moving parts.

Heat pipes usually utilize a porous wick to transport working fluid from the condenser to the evaporator. This is not preferred because of the wick’s high cost of fabrication and low thermal conductivity. Thermosyphons on the other hand, are gravity-assisted wickless heat pipes that utilize gravitational force to transport the working fluid from the condenser section to the evaporator section.

Thermosyphons usually consist of two phases and are cylindrical in shape. However, a flat thermosyphon is more advantageous as they can cool electronic chips at a shorter distance than a conventional cylindrical thermosyphon that requires multiple units and longer distances.

In this study, the authors Mr. Praveen Dhanalakota, Mr. Hemanth Dileep, Mr. Laxman Kumar Malla, Prof. Pallab Sinha Mahapatra, and Prof. Arvind Pattamatta from the Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai, India, have developed a novel Integrated Flat Thermosyphon Heat Sink (IFTHS) with enhanced performance.

The IFTHS has a condenser with integrated hollow fins wherein the inner surface of the hollow fins is used for condensation, and the outer surface is used for air-side convective cooling.

This is the earliest attempt to develop the novel IFTHS with hollow fins condenser.

An evaporator with minichannels and a superhydrophobic condenser were added to improve the performance by 36 percent.

It was found that the IFTHS performed better than a flat thermosyphon with a condenser with solid fins. The thermal performance of the IFTHS was found to be the best at a filling ratio of 40 percent.

The thermal performance, electronic component lifespan, weight reduction, and energy savings were also found to be better with the novel IFTHS compared to a flat thermosyphon with solid fins.

Electronic component lifespan was increased and the room air cooling load was also reduced with the IFTHS.

Thus IFTHS contributes to more energy-efficient chip-level thermal management in energy-intensive data centers.

Prof. Marco Marengo, Professor of Thermal Sciences, from the Department of Civil Engineering and Architecture, University of Pavia, Pavia, Italy, pointed out the relevant details of this study, thus explaining the importance of this work with the following comments: “The study presents the Integrated Flat Thermosyphon System (IFTHS), which demonstrates improved performance. The study analyzes the thermal characteristics of the IFTHS at various filling ratios to determine the optimal ratio. Additionally, it investigates the effects of a minichannel evaporator and a superhydrophobic condenser on the IFTHS’s performance enhancement at the optimal filling ratio. The IFTHS incorporates a condenser with integrated hollow fins, utilizing both inner and outer surfaces for condensation and air-side convective cooling. By providing a larger condensation area within the same space, the IFTHS outperforms a flat thermosyphon with solid fins. This technology has the potential to enhance the cooling effectiveness of these systems in energy-intensive sectors, and in particular for data centres.”

Article by Akshay Anantharaman
Click here for the original link to the paper