Comparison Analysis of Liquid and Air-cooling Systems for GPU

Abstract

In order to increase reliability and prevent early failure, heat produced by electronic components and circuits must be drained. Heat sinks, fans, and other air-cooling devices, as well as alternative computer cooling methods like liquid cooling, can all be used as heat dissipation techniques. Here the paper\'s main focus is on a numerical analysis of temperature distribution in a GPU scenario with various input velocity circumstances, including v = 1 m/s, 3 m/s, and 5 m/s. Air and water are the two distinct fluids employed in this investigation to cool the graphics card. An analysis of the fluid flow and heat transfer simulation of a desktop graphics card heat sink is conducted using the CFD software ANSYS Fluent. According to the findings, cooling with water was 10% more effective than cooling with air. The outcome also shows an inverse correlation between the graphic card chip\'s intake velocity and temperature. The rate of heat transfer to the heat sink increases as the inflow velocity rises which is helped by the convection.

Introduction

I. INTRODUCTION

In recent years, the quantity of heat created by PCs or other electronic devices has increased in tandem with improvements in the performance of GPU, CPU, RAM, and other components. To increase reliability and prevent early failure, heat produced by electronic devices and circuits must be dissipated. (Tasawur et al, 2010). As temperature increases, the performance of the graphics card causing a drop in graphic performance and in an extreme case, causing a computer operation to stop (Zambri et al, 2019). So, in order to prevent thermal throttling and increase the efficiency of the graphic card different heat sinks were developed for air cooling based upon the power consumed and the purpose used for. In order to address the problem of the graphics card overheating, a computational fluid dynamics (CFD) simulation is run to examine and monitor the transfer of heat flow within a computer case and heat sink.

The heat flow happens due to Conduction and Convection mainly. Conduction is the process whereby energy is transferred from the more energetic material particles to the nearby, less energetic ones as a result of particle contact. Convection is the method of transferring heat from a solid surface to the nearby moving liquid or gas (Yunus, 1997). In this scenario the conduction happens when chip transfers heat to the heat sink by surface contact and convection when fluid flows and absorbs the heat. (Martin, 1995) created a multimode heat sink for an electrical module. In specifically, the rig was positioned so that conduction or convection cooling could take place inside an electronic module mounting rack.

II. LITERATURE REVIEW

Many researches have done on cooling systems for different types of graphic card using different types of cooling system. A few of them are

According to study (Zambri et al, 2019) the rate of heat transmission was boosted by modifying the form and size of the heat sink. Different heat sinks of various types were created to cool the graphic card, and when tested at various temperatures, one of the designs was shown to be more effective than the others at drawing heat away from the graphic card. Convection develops over time, the heat generated by the graphics card initially targets the region around it. Later, using a convection mechanism, the heat steadily moved to the top section of the CPU case.

In another study (T. Abbas, 2010) when using the pipe method, you get high temperature readings and maximum temperature enhancement, while using the thermoelectric cooler method results in less temperature enhancement, a slower process, and a processor temperature that is roughly constant. When using the water-cooling method, you get a large heat transfer rate and maximum temperature enhancement. The results of this inquiry show that the thermoelectric cooler technique is the best approach since the processor temperature is stable and the operating temperature increases are minimal, but the procedure takes a long time because of the system's exhaust.

Study (Baojun, 2020) shows that thermal control is a challenge that can only be solved by liquid cooling technology. It is possible to identify the direction of development of liquid cooling technology by comprehending and studying the function, principle, features, and applications of the technology. The future of will be highly open for liquid cooling technologies.

III. METHODOLOGY

The methodology in the paper is divided into several parts but mainly into four parts. Firstly, the graphic card is modelled into the Autodesk Inventor. Secondly, it is defined by encloser. Thirdly, it is meshed using ANSYS software and finally with applying boundary conditions to analyse on ANSYS Fluent.

A. CAD Model

The design for graphic card is divided into two sections one for fluid as air and the other as water. A graphic card which was similar in the market was chosen for analysis. GT 710 inspired model was modelled on the graphic card with similar dimensions but reduction in the number of fins and the increasing the distance between the fins. This graphic card acts as an entry level and daily driver for many.

1)  Fluid as AIR:  This type of graphic cards heat sinks are equipped with fins. Fins are expanded surfaces or fins are typically employed to improve heat transmission between the primary surface and the surrounding fluid (Ambarish, 2019).

V. COMPARISONAL ANALYSIS

From Table IV. we can see that for when inlet velocity is 1 m/s the maximum temperature between air-based and water-based have a difference of 12K. when inlet velocity is 3 m/s the difference of temperatures being 7K and when inlet velocity is 5 m/s the difference of temperature being 6K.

Table IV. Maximum temperature attained by graphic card for different velocities and fluid

In contrast to pure conduction, liquid cooling "efficiently distributes heat over larger convective surface area (radiator), allowing for decreased fan speeds (better acoustics) or higher overall power," (Mark, 2019). Water having a higher specific heat capacity and thermal conductivity than air becomes more efficient in transporting heat away from heat sources in graphics cards (Atila, 2021)

VII. ACKNOWLEDGEMENT

It would not have been possible without the assistance of my PhD professor, Sebastian Uppapalli, who has guided me through every phase of my thesis. I'm grateful for the opportunity he gave me.

I would also want to thank my PhD professor Pankaj Narke, who's remarkable professionalism and experience enabled me to complete this research report.

Last but not least, I want to thank my co-workers Chirag and Sahil, whose astute observations really assisted me in avoiding several mistakes.

Conclusion

We performed numerical simulations to test the effectiveness of heat transmission through conduction and convection modes for two different based fluids on graphic card. Conduction happened due to surface contact of the heat sink and the chip (air-based cooling) and water block with chip (water-based cooling) and convection due to transfer of heat from heat sink to air (air-based cooling) and transfer of heat from copper block to water (water-based cooling). From comparison analysis we draw the following conclusion: - 1) The comparison of temperature distribution contour for heat sink (air-based) and water block (water-based) at a different inlet velocity (v = 1 m/s, 3 m/s and 5m/s). Based on the contour temperature distribution, shown that maximum temperature retained by the graphic card for water-based cooling is less than air-based cooling 2) While simulating we could see iterations were less for air-based cooling compared to water-based cooling which tells that heat being removed for air-cooling was less compared to water-based cooling. 3) The efficiency of water-based cooling on an average was nearly about 10% better than air-based cooling which proves that water-based cooling is better than air-based cooling. Although air cooling has benefits over liquid cooling in terms of manufacturing costs, space utilisation rates, structural complexity, and other factors, several studies have shown that liquid cooling is almost one of the most promising cooling systems (Nan et al, 2020).

References

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Copyright

Copyright © 2023 Prateeth DV. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.