Piranha Pin Fin (PPF) — Advanced flow boiling microstructures with low surface tension dielectric fluids

Woodcock, Corey; Yu, Xueli; Plawsky, Joel L.; Peles, Yoav

doi:10.1016/j.ijheatmasstransfer.2015.06.072

Cited by 84 publications

(13 citation statements)

References 36 publications

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“…While liquid-vapor phase-change techniques such as flow boiling in microchannels have been investigated for conductive 7,8 as well as dielectric fluids [9][10][11] , significant limitations associated with flow instabilities and power consumption prohibit practical implementation 8,12 .…”

Section: Introductionmentioning

confidence: 99%

Nanoporous membrane device for ultra high heat flux thermal management

et al. 2018

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High power density electronics are severely limited by current thermal management solutions which are unable to dissipate the necessary heat flux while maintaining safe junction temperatures for reliable operation. We designed, fabricated, and experimentally characterized a microfluidic device for ultra-high heat flux dissipation using evaporation from a nanoporous silicon membrane. With~100 nm diameter pores, the membrane can generate high capillary pressure even with low surface tension fluids such as pentane and R245fa. The suspended ultra-thin membrane structure facilitates efficient liquid transport with minimal viscous pressure losses. We fabricated the membrane in silicon using interference lithography and reactive ion etching and then bonded it to a high permeability silicon microchannel array to create a biporous wick which achieves high capillary pressure with enhanced permeability. The back side consisted of a thin film platinum heater and resistive temperature sensors to emulate the heat dissipation in transistors and measure the temperature, respectively. We experimentally characterized the devices in pure vaporambient conditions in an environmental chamber. Accordingly, we demonstrated heat fluxes of 665 ± 74 W/cm 2 using pentane over an area of 0.172 mm × 10 mm with a temperature rise of 28.5 ± 1.8 K from the heated substrate to ambient vapor. This heat flux, which is normalized by the evaporation area, is the highest reported to date in the pure evaporation regime, that is, without nucleate boiling. The experimental results are in good agreement with a high fidelity model which captures heat conduction in the suspended membrane structure as well as non-equilibrium and sub-continuum effects at the liquid-vapor interface. This work suggests that evaporative membrane-based approaches can be promising towards realizing an efficient, high flux thermal management strategy over large areas for high-performance electronics.

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Section: Introductionmentioning

confidence: 99%

Nanoporous membrane device for ultra high heat flux thermal management

et al. 2018

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“…A variety of heat sink designs have been employed to dissipate larger heat fluxes by delaying CHF or reducing the pressure drop in two-phase operation compared to a conventional design with straight, parallel channels fed by a single header. These designs have implemented one or more of features such as vapor venting [10], pin-fins and interrupted channels of various shapes and configurations [10][11][12], wick structures to aid in thin film evaporation [13][14][15], microchannels with reentrant cavities and/or inlet restrictors [16], microgaps [17], arrays of jets [18][19][20][21], diverging channels [22,23], microchannels fed with tapered manifolds [24], and stacked heat sinks [25]. Heat fluxes as high as 1127 W/cm² have been dissipated with dielectric fluids [26] using a 10 mm × 20 mm copper heat sink that incorporated both flow boiling in microchannels and jet impingement.…”

Section: Introductionmentioning

confidence: 99%

A hierarchical manifold microchannel heat sink array for high-heat-flux two-phase cooling of electronics

Drummond

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Sinanis

et al. 2018

International Journal of Heat and Mass Transfer

298

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High-heat-flux removal is necessary for next-generation microelectronic systems to operate more reliably and efficiently. Extremely high heat removal rates are achieved in this work using a hierarchical manifold microchannel heat sink array. The microchannels are imbedded directly into the heated substrate to reduce the parasitic thermal resistances due to contact and conduction resistances. Discretizing the chip footprint area into multiple smaller heat sink elements with high-aspect-ratio microchannels ensures shortened effective fluid flow lengths. Phase change of high fluid mass fluxes can thus be accommodated in micron-scale channels while keeping pressure drops low compared to traditional, microchannel heat sinks.A thermal test vehicle, with all flow distribution components heterogeneously integrated, is fabricated to

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“…To suppress flow instability and to enhance heat transfer, recent studies have focused on incorporating various structures in microchannels, such as inlet restrictors [12][13][14], artificial nucleation sites [14,15], vapor venting membranes [16][17][18], micro pin fins [19][20][21], and nanowire-coated surfaces [22][23][24] integrated into the microchannel.…”

Section: Introductionmentioning

confidence: 99%

“…These surface structures have length scales much smaller than the height of the microchannel, and thus are different from micro pin fins which extend to the ceiling of the microchannel [19][20][21]. We fabricated and characterized microchannels with well-defined micropillar arrays on the bottom channel wall, where heat was applied.…”

Section: Introductionmentioning

confidence: 99%