Investigation of subcooled and saturated boiling heat transfer mechanisms, instabilities, and transient flow regime maps for large length-to-diameter ratio micro-channel heat sinks

Lee, Seunghyun; Devahdhanush, V.S.; Mudawar, Issam

doi:10.1016/j.ijheatmasstransfer.2018.02.020

Cited by 55 publications

(9 citation statements)

References 93 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, researchers have focused more on the other three instability modes [ 134 ]. Lee et al [ 170 ] investigated the flow instability caused by pressure oscillation in the saturated boiling region. A flow oscillation schematic was obtained based on experimental observations, as in Figure 21 .…”

Section: Flow and Heat Transfer Mechanisms Under The Coupling Effect ...mentioning

confidence: 99%

See 1 more Smart Citation

A Review of the Complex Flow and Heat Transfer Characteristics in Microchannels

Zhang

Zou

2023

Micromachines

View full text Add to dashboard Cite

Continuously improving heat transfer efficiency is one of the important goals in the field of energy. Compact heat exchangers characterized by microscale flow and heat transfer have successfully provided solutions for this purpose. However, as the characteristic scale of the channels decreases, the flow and heat transfer characteristics may differ from those at the conventional scale. When considering the influence of scale effects and changes in special fluid properties, the flow and heat transfer process becomes more complex. The conclusions of the relevant studies have not been unified, and there are even disagreements on some aspects. Therefore, further research is needed to obtain a sufficient understanding of flow structure and heat transfer mechanisms in microchannels. This article systematically reviews the research about microscale flow and heat transfer, focusing on the flow and heat transfer mechanisms in microchannels, which is elaborated in the following two perspectives: one is the microscale single-phase flow and heat transfer that only considers the influence of scale effects, the other is the special heat transfer phenomena brought about by the coupling of microscale flow with special fluids (fluid with phase change (pseudophase change)). The microscale flow and heat transfer mechanisms under the influence of multiple factors, including scale effects (such as rarefaction, surface roughness, axial heat conduction, and compressibility) and special fluids, are investigated, which can meet the specific needs for the design of various microscale heat exchangers.

show abstract

Section: Flow and Heat Transfer Mechanisms Under The Coupling Effect ...mentioning

confidence: 99%

Section: Figurementioning

confidence: 99%

A Review of the Complex Flow and Heat Transfer Characteristics in Microchannels

Zhang

Zou

2023

Micromachines

View full text Add to dashboard Cite

show abstract

“…Moreover, the average HTC was depending on the applied heat flux than mass velocity, therefore, the nucleate boiling was dominant. [15] examined the impact of subcooling degree at the inlet on the flow boiling behaviour of refrigerant R-134a through 100 microchannel of length 609.5 mm and square cross section (1×1) mm 2 . Their results showed that the subcooling zone is separated into PDB and FDB.…”

Section: Introductionmentioning

confidence: 99%

Numerical Investigation of the Impact of Subcooling Inlet on Water Flow Boiling Heat Transfer Through a Microchannel

Al-Waaly

2024

ejuow

View full text Add to dashboard Cite

The effect of subcooling inlet has a big effect of the flow patterns for the flow boiling through a microchannel. Higher subcooling lower mass flux will delay the nucleate boiling and vice versa. The water flow boiling inside a microchannel has been analyzed numerically. The microchannel depth was 0.24 mm while the length was 40 mm. The supplied heat fluxes were 500 kW·m-2, 1000 kW·m-2and 1500 kW·m-2 with mass velocities of 400 kg·m-2·s-1 and 800 kg·m-2·s-1. The degrees of subcoooling of inlet water were 5oC, 10oC, 15oC, 20oC, and 25oC. The results showed that the degree subcooling has a considerable impact on both the wall temperature and flow patterns. The rise in the degree of subcooling kept the nucleate flow boiling and retarded the development of convective boiling. In addition, there was a reflection point at which the impact of heat flux on the average of the convective coefficient of heat transfer was altered. The increase in the heat flux may lead to an increase or reduction in the average HTC with respect to the location of the reflection point. The reflection points were 7oC and 5oC for the mass velocities 400 kg·m-2·s-1 and 800 kg·m-2·s-1. Thus, both the degree of subcooling and the heat flux should be simultaneously considered when it comes to the enhancement of HTC during the flow boiling inside the microchannels.

show abstract

“…Visual interpretation of changes in flow regimes due to vapour backflow/reverse flow can be grouped to create flow stability maps and dry-out maps [16]. These maps indicate unstable and stable regions by using either the mass flux and vapour quality as coordinates, or the phase-change number and sub-cooling number [17].…”

Section: Introductionmentioning

confidence: 99%