Effects of jet pattern on two-phase performance of hybrid micro-channel/micro-circular-jet-impingement thermal management scheme

Boiling water in small channels that are formed along turbine blades has been examined since the 1970s as a means to dissipating large amounts of heat. Later, similar geometries could be found in cooling systems for computers, fusion reactors, rocket nozzles, avionics, hybrid vehicle power electronics, and space systems. This paper addresses (a) the implementation of two-phase micro-channel heat sinks in these applications, (b) the fluid physics and limitations of boiling in small passages, and effective tools for predicting the thermal performance of heat sinks, and (c) means to enhance this performance. It is shown that despite many hundreds of publications attempting to predict the performance of two-phase micro-channel heat sinks, there are only a handful of predictive tools that can tackle broad ranges of geometrical and operating parameters or different fluids. Development of these tools is complicated by a lack of reliable databases and the drastic differences in boiling behavior of different fluids in small passages. For example, flow boiling of certain fluids in very small diameter channels may be no different than in macro-channels. Conversely, other fluids may exhibit considerable ‘confinement’ even in seemingly large diameter channels. It is shown that cutting-edge heat transfer enhancement techniques, such as the use of nano-fluids and carbon nanotube coatings, with proven merits to single-phase macro systems, may not offer similar advantages to microchannel heat sinks. Better performance may be achieved by careful optimization of the heat sink’s geometrical parameters and by adapting a new class of hybrid cooling schemes that combine the benefits of micro-channel flow with those of jet impingement.

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Assessing the Performance of Advanced Cooling Techniques on Thermal Management of Next-Generation Power Electronics

ASME 2019 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems ◽

10.1115/ipack2019-6311 ◽

2019 ◽

Author(s):

Palash V. Acharya ◽

Vaibhav Bahadur ◽

Robert Hebner ◽

Abdelhamid Ouroua ◽

Shannon Strank

Keyword(s):

Power Electronics ◽

Thermal Management ◽

Heat Dissipation ◽

Jet Impingement ◽

Heat Sinks ◽

Junction Temperature ◽

Two Phase ◽

Maximum Heat ◽

Starting Point ◽

Electronics Packages

Abstract Rapid miniaturization alongwith increasing heat loads in power electronics devices like insulated-gate bipolar transistors (IGBTs) have necessitated the need for advanced thermal management technologies in the packaging of these devices. This study quantifies the benefits of key advanced thermal management solutions for packaging of power electronics packages. Thermal resistance network modeling is used to estimate the maximum heat flux that can be dissipated by an IGBT package, while maintaining the junction temperature below 125 °C and 200 °C for silicon and silicon carbide (wide bandgap material) devices, respectively. While the model is completely analytical, it does address important complexities associated with heat flow in packages via the use of a sub-model to account for thermal spreading. The advanced cooling technologies evaluated in this study include the use of high thermal conductivity polymer heat sinks, double-sided heat sinking of packages, liquid cooling (single and two-phase), jet impingement and spray cooling. Additionally, combinations of these cooling technologies are evaluated as well. The heat dissipation achievable from these technologies is compared with that from an air cooled copper heat sink (baseline). The results of this study provide insights and a starting point for selecting thermal management technologies (or combinations) based on the heat dissipation requirements of power electronics packages.

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Low-temperature two-phase micro-channel cooling for high-heat-flux thermal management of defense electronics

2008 11th Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems ◽

10.1109/itherm.2008.4544263 ◽

2008 ◽

Cited By ~ 1

Author(s):

Jaeseon Lee ◽

Issam Mudawar

Keyword(s):

Heat Flux ◽

Low Temperature ◽

Thermal Management ◽

High Heat ◽

High Heat Flux ◽

Micro Channel ◽

Two Phase

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Fuzzy-Based Thermal Management Scheme for 3D Chip Multicores with Stacked Caches

Electronics ◽

10.3390/electronics9020346 ◽

2020 ◽

Vol 9 (2) ◽

pp. 346 ◽

Cited By ~ 1

Author(s):

Lili Shen ◽

Ning Wu ◽

Gaizhen Yan

Keyword(s):

Power Consumption ◽

Thermal Management ◽

System Performance ◽

Control Policy ◽

Three Dimension ◽

Processor Core ◽

Management Scheme ◽

And Performance ◽

On Chip ◽

Silicon Vias

By using through-silicon-vias (TSV), three dimension integration technology can stack large memory on the top of cores as a last-level on-chip cache (LLC) to reduce off-chip memory access and enhance system performance. However, the integration of more on-chip caches increases chip power density, which might lead to temperature-related issues in power consumption, reliability, cooling cost, and performance. An effective thermal management scheme is required to ensure the performance and reliability of the system. In this study, a fuzzy-based thermal management scheme (FBTM) is proposed that simultaneously considers cores and stacked caches. The proposed method combines a dynamic cache reconfiguration scheme with a fuzzy-based control policy in a temperature-aware manner. The dynamic cache reconfiguration scheme determines the size of the cache for the processor core according to the application that reaches a substantial amount of power consumption savings. The fuzzy-based control policy is used to change the frequency level of the processor core based on dynamic cache reconfiguration, a process which can further improve the system performance. Experiments show that, compared with other thermal management schemes, the proposed FBTM can achieve, on average, 3 degrees of reduction in temperature and a 41% reduction of leakage energy.

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Thermal Characterization of Interlayer Microfluidic Cooling of Three-Dimensional Integrated Circuits With Nonuniform Heat Flux

Journal of Heat Transfer ◽

10.1115/1.4000885 ◽

2010 ◽

Vol 132 (4) ◽

Cited By ~ 64

Author(s):

Yoon Jo Kim ◽

Yogendra K. Joshi ◽

Andrei G. Fedorov ◽

Young-Joon Lee ◽

Sung-Kyu Lim

Keyword(s):

Integrated Circuits ◽

Mass Flow Rate ◽

Thermal Management ◽

Mass Flow ◽

Flow Rate ◽

Single Phase ◽

Hot Spot ◽

Three Dimensional ◽

Two Phase ◽

Two Phase Cooling

It is now widely recognized that the three-dimensional (3D) system integration is a key enabling technology to achieve the performance needs of future microprocessor integrated circuits (ICs). To provide modular thermal management in 3D-stacked ICs, the interlayer microfluidic cooling scheme is adopted and analyzed in this study focusing on a single cooling layer performance. The effects of cooling mode (single-phase versus phase-change) and stack/layer geometry on thermal management performance are quantitatively analyzed, and implications on the through-silicon-via scaling and electrical interconnect congestion are discussed. Also, the thermal and hydraulic performance of several two-phase refrigerants is discussed in comparison with single-phase cooling. The results show that the large internal pressure and the pumping pressure drop are significant limiting factors, along with significant mass flow rate maldistribution due to the presence of hot-spots. Nevertheless, two-phase cooling using R123 and R245ca refrigerants yields superior performance to single-phase cooling for the hot-spot fluxes approaching ∼300 W/cm2. In general, a hybrid cooling scheme with a dedicated approach to the hot-spot thermal management should greatly improve the two-phase cooling system performance and reliability by enabling a cooling-load-matched thermal design and by suppressing the mass flow rate maldistribution within the cooling layer.

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Two-Phase Flow and Heat Transfer in Rectangular Micro-Channels

Heat Transfer: Volume 3 ◽

10.1115/ht2003-47050 ◽

2003 ◽

Cited By ~ 2

Author(s):

Weilin Qu ◽

Seok-Mann Yoon ◽

Issam Mudawar

Keyword(s):

Heat Transfer ◽

Pressure Drop ◽

Flow Pattern ◽

Two Phase Flow ◽

Flow Patterns ◽

Heat Sinks ◽

Phase Flow ◽

Micro Channel ◽

Two Phase ◽

Micro Channels

Knowledge of flow pattern and flow pattern transitions is essential to the development of reliable predictive tools for pressure drop and heat transfer in two-phase micro-channel heat sinks. In the present study, experiments were conducted with adiabatic nitrogen-water two-phase flow in a rectangular micro-channel having a 0.406 × 2.032 mm cross-section. Superficial velocities of nitrogen and water ranged from 0.08 to 81.92 m/s and 0.04 to 10.24 m/s, respectively. Flow patterns were first identified using high-speed video imaging, and still photos were then taken for representative patterns. Results reveal that the dominant flow patterns are slug and annular, with bubbly flow occurring only occasionally; stratified and churn flow were never observed. A flow pattern map was constructed and compared with previous maps and predictions of flow pattern transition models. Annual flow is identified as the dominant flow pattern for conditions relevant to two-phase micro-channel heat sinks, and forms the basis for development of a theoretical model for both pressure drop and heat transfer in micro-channels. Features unique to two-phase micro-channel flow, such as laminar liquid and gas flows, smooth liquid-gas interface, and strong entrainment and deposition effects are incorporated into the model. The model shows good agreement with experimental data for water-cooled heat sinks.

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