Experimental Investigation on Fluid Flow in an Inclined Open Rectangular Microgrooves Heat Sink With Micro-PIV

The paper investigates the fluid flow in an inclined open rectangular microgrooves heat sink using LaVision-assembled micro-PIV system. The images of the accommodation stage and the corner flow stage at inclined 15 degrees angle with heat flux of 0.09W/cm2 were recorded by a CCD camera with the speed of 10 frames per second. The velocity profile at inclined 15 degrees angle with heat flux of 0.14W/cm2 was acquired by using the analyzing software DaVis 8.1. In accommodation stage, X-Y-Z scanning table was adjusted vertically and horizontally to investigate the velocity field of different focused planes. Results show that the experimental images of the accommodation stage and the corner flow stage verify the predictions proposed by Catton and Stroes that there exist accommodation stage and corner flow stage and no jump-like stage proposed by Nilson et al. Flow in microgroove driven by capillary force is very slow and the velocity is less than 1mm per second. In evaporating thin film region, from the left side to the right side of the microgroove, the velocity increases and velocity of the interface is the highest. In lower meniscus region, the velocity increases and then decreases.

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Experimental Investigation on Shape of the Meniscus in Open Rectangular Microgrooves Heat Sinks With Micro-PIV

ASME 2013 11th International Conference on Nanochannels, Microchannels, and Minichannels ◽

10.1115/icnmm2013-73051 ◽

2013 ◽

Author(s):

Dong Yu ◽

Xuegong Hu ◽

Chaohong Guo ◽

Dawei Tang ◽

Xuelei Nie ◽

...

Keyword(s):

Heat Flux ◽

Experimental Investigation ◽

Cross Sections ◽

Ccd Camera ◽

Axial Direction ◽

Heat Sinks ◽

Transfer Condition ◽

Micro Piv ◽

Evaporation Heat ◽

Evaporation Heat Transfer

This paper presents the experimental investigation on shape of the meniscus in cross sections along the axial direction of open rectangular microgrooves heat sinks with input heat flux under pure evaporation heat transfer condition. The images of the shape of the meniscus in rectangular open microgrooves heat sinks were recorded by a CCD camera with the speed of 10 frames per second. Microgrooves heat sinks were placed in four inclined angles, horizon, inclined 15 degrees, inclined 25 degrees and inclined 35 degrees, and heat flux is 0.09W/cm2, 0.14 W/cm2 and 0.25 W/cm2. The results show that the shape of the meniscus is parabolic not round. When the microgrooves heat sinks are placed horizontally, the shape of the meniscus and the curvature of the meniscus in cross sections changes little along the axial direction of the microgrooves. When the microgrooves heat sinks were placed inclined 35 degrees, the meniscus moves downward to the microgroove bottom. At the same distance to the reservoir and the same heat flux, the curvature of the meniscus in inclined 35 degrees is larger than that in inclined 25 degrees, and similarly, the curvature of the meniscus in inclined 25 degrees is larger than that in inclined 15 degrees. While at the same heat flux, the microgrooves heat sink is placed in inclined 35 degrees, the curvature of the meniscus increases with the increase of the distance to the reservoir.

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Tailoring the fluid flow distribution in a parallel mini-channel heat sink under multiple-peak heat flux

Thermal Science and Engineering Progress ◽

10.1016/j.tsep.2021.101182 ◽

2021 ◽

pp. 101182

Author(s):

Yijun Li ◽

Stéphane Roux ◽

Cathy Castlain ◽

Lingai Luo ◽

Yilin Fan

Keyword(s):

Heat Flux ◽

Fluid Flow ◽

Heat Sink ◽

Flow Distribution ◽

Multiple Peak ◽

Peak Heat Flux

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Effects of Inlet/Outlet Manifold Configuration on the Thermo-Hydrodynamic Performance of Recharging Microchannel Heat Sink

Journal of Thermal Science and Engineering Applications ◽

10.1115/1.4047940 ◽

2020 ◽

Vol 13 (3) ◽

Author(s):

Sangram Kumar Samal ◽

Manoj Kumar Moharana

Keyword(s):

Heat Flux ◽

Fluid Flow ◽

Thermal Performance ◽

Heat Sink ◽

Flow Distribution ◽

Hydrodynamic Performance ◽

Bottom Surface ◽

High Heat Flux ◽

Microchannel Heat Sink ◽

Power Requirement

Abstract Thermal performance of microchannel heat sink can be augmented by designing inlet/outlet manifolds such that fluid flow distribution is uniform across microchannels. In this work, the effect of inlet/outlet manifold configurations on the thermo-hydrodynamic performance of recharging microchannel heat sink (RMCHS) is investigated numerically. For this purpose branched, rectangular, trapezoidal, and triangular manifold configurations are considered. All the numerical simulations are performed for channel Reynolds number of 50–300 and constant heat flux of 10 W/cm2 applied on the substrate bottom surface of the RMCHS. The results reveal that branched manifold configuration shows uniform fluid flow distribution across all the microchannels of heat sink and also shows uniform temperature distribution on the substrate bottom surface of RMCHS. Branched manifold configuration reduces thermal resistance by 16% and enhances average Nusselt number by 9.5% compared to rectangular manifold configuration. However, branched manifold configuration shows higher pressure drop in spite of enhancements in thermal performance and flow distribution uniformity. Overall performance analysis indicates that RMCHS with branched manifold configuration can be advantageous for high heat flux removal applications if there is no restriction on pumping power requirement.

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A Compact Nanostructure Enhanced Heat Sink With Flow in a Rectangular Channel

ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, Volume 2 ◽

10.1115/esda2010-25336 ◽

2010 ◽

Cited By ~ 1

Author(s):

Muhsincan Sesen ◽

Berkay Arda Kosar ◽

Ali Kosar ◽

Wisam Khudhayer ◽

Berk Ahmet Ahishalioglu ◽

...

Keyword(s):

Thin Film ◽

Heat Transfer ◽

Heat Flux ◽

Heat Sink ◽

Constant Pressure ◽

Rectangular Channel ◽

Constant Heat Flux ◽

Nanorod Arrays ◽

Constant Heat ◽

Copper Thin Film

This paper reports a compact nanostructure based heat sink. The system has an inlet and an outlet valve similar to a conventional heat sink. From the inlet valve, pressurized deionized-water is propelled into a rectangular channel (of dimensions 24mm×59mm×8mm). This rectangular channel houses a nanostructured plate, on which ∼600 nm long copper nanorod arrays with an average nanorod diameter of 150 nm are integrated to copper thin film coated on silicon wafer surface. Forced convective heat transfer characteristics of the nanostructured plate are investigated using the experimental setup and compared to the results from a flat plate of copper thin film deposited on silicon substrate. Nanorod arrays act as fins over the plate which enhances the heat transfer from the plate. Excess heat generating small devices are mimicked through a small heat generator placed below the nanostructured plate. Constant heat flux is provided through the heat generator. Thermocouples placed on the heater surface are utilized to gather the surface temperature data. Constant pressure drop across the heat sink and constant heat flux values are varied in order to obtain the correlation between heat removal rate and input power. Volumetric flow rate was measured as a function of the constant pressure drop. In this study, it was proved that nanostructured surfaces have the potential to be a useful in cooling of small and excessive heat generating devices such as MEMS (Micro Electro Mechanical Systems) and microprocessors.

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The effect of an aluminum heat-sink layer on the laser-induced amorphization of SiOx/TeGeSn/SiOx phase-change recording films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154846 ◽

1989 ◽

Vol 47 ◽

pp. 574-575

Author(s):

Matthew R. Libera ◽

Martin Chen

Keyword(s):

Thin Film ◽

Phase Change ◽

Heat Sink ◽

Multilayer Film ◽

Glassy Phase ◽

Film Structure ◽

Glass Forming ◽

Active Storage ◽

Dielectric Layers ◽

Amorphous States

Phase-change erasable optical storage is based on the ability to switch a micron-sized region of a thin film between the crystalline and amorphous states using a diffraction-limited laser as a heat source. A bit of information can be represented as an amorphous spot on a crystalline background, and the two states can be optically identified by their different reflectivities. In a typical multilayer thin-film structure the active (storage) layer is sandwiched between one or more dielectric layers. The dielectric layers provide physical containment and act as a heat sink. A viable phase-change medium must be able to quench to the glassy phase after melting, and this requires proper tailoring of the thermal properties of the multilayer film. The present research studies one particular multilayer structure and shows the effect of an additional aluminum layer on the glass-forming ability.

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