Comparison of thermal performance between plate-fin and pin-fin heat sinks in natural convection

Heat sinks are used in modern electronic packaging system to enhance and sustain system thermal performance by dissipating heat away from IC components. Pin fins are commonly used in heat sink applications. Conventional metallic pins fins are efficient in low Biot number range whereas high thermal performance can be achieved in high Biot number regions with orthotropic composite pin fins due to their adjustable thermal properties. However, several challenges related to performance as well as manufacturing need to be addressed before they can be successfully implemented in a heat sink design. A heat sink assembly with metallic base plate and polymer composite pin fins is a solution to address manufacturing constraints. During the service life of an electronic packaging, the heat sink assembly is subjected to power cycles. Cyclic thermal stresses will be important at the pin-fin and base-plate interface due to thermal mismatch. The cyclic nature of stresses can lead to fatigue failure that will affect the reliability of the heat sink and electronic packaging. A finite element model of the heat sink is used to investigate the thermal stress cyclic effect on thermo-mechanical reliability performance. The aim is to assess the reliability performance of the epoxy bond at the polymer composite pin fins and metallic base plate interface in a heat-sink assembly.

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S-Shaped Pin-Fins for Enhancement of Overall Performance of the Pin-Fin Heat Sink

ASME 2010 3rd Joint US-European Fluids Engineering Summer Meeting: Volume 1, Symposia – Parts A, B, and C ◽

10.1115/fedsm-icnmm2010-31164 ◽

2010 ◽

Author(s):

T. J. John ◽

B. Mathew ◽

H. Hegab

Keyword(s):

Reynolds Number ◽

Thermal Resistance ◽

Thermal Performance ◽

Heat Sink ◽

Heat Sinks ◽

Uniform Heat Flux ◽

Pumping Power ◽

Pin Fin ◽

Pin Fins ◽

Overall Performance

In this paper the authors are studying the effect of introducing S-shaped pin-fin structures in a micro pin-fin heat sink to enhance the overall thermal performance of the heat sinks. For the purpose of evaluating the overall thermal performance of the heat sink a figure of merit (FOM) term comprising both thermal resistance and pumping power is introduced in this paper. An optimization study of the overall performance based on the pitch distance of the pin-fin structures both in the axial and the transverse direction, and based on the curvature at the ends of S-shape fins is also carried out in this paper. The value of the Reynolds number of liquid flow at the entrance of the heat sink is kept constant for the optimization purpose and the study is carried out over a range of Reynolds number from 50 to 500. All the optimization processes are carried out using computational fluid dynamics software CoventorWARE™. The models generated for the study consists of two sections, the substrate (silicon) and the fluid (water at 278K). The pin fins are 150 micrometers tall and the total structure is 500 micrometer thick and a uniform heat flux of 500KW is applied to the base of the model. The non dimensional thermal resistance and nondimensional pumping power calculated from the results is used in determining the FOM term. The study proved the superiority of the S-shaped pin-fin heat sinks over the conventional pin-fin heat sinks in terms of both FOM and flow distribution. S-shaped pin-fins with pointed tips provided the best performance compared to pin-fins with straight and circular tips.

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Orientation effects on thermal performance of radial heat sinks with a concentric ring subject to natural convection

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2015.06.012 ◽

2015 ◽

Vol 90 ◽

pp. 102-108 ◽

Cited By ~ 20

Author(s):

Bin Li ◽

Chan Byon

Keyword(s):

Natural Convection ◽

Thermal Performance ◽

Heat Sinks ◽

Concentric Ring ◽

Orientation Effects ◽

Radial Heat

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Heat Transfer Analysis and Performance Measurements of Hollow Pin-fin in Natural Convection

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.f1140.0886s19 ◽

2019 ◽

Vol 8 (6S) ◽

pp. 727-731

Keyword(s):

Heat Transfer ◽

Natural Convection ◽

Temperature Distribution ◽

Convective Heat Transfer ◽

Convective Heat ◽

Thermal Performance ◽

Temperature Drop ◽

Heat Transfer Analysis ◽

Pin Fin ◽

And Performance

The Fin act as dissipiating elements, selection of proper geometry plays crusial role in increasing the rate of heat transfer and performance of the system. This work has been undertaken to investigate and compare thermal performance of solid and hollow pin-fin. Heat transfer analysis of solid and hollow pin fin carried and the results was compared with the experimental results. experiment was conducted to analyze the natural convection around solid hollow pin fin, and compare thermal performance of hollow pin fin with the solid pin fin of same dimension and orientation. The experimental result of temperature distribution shows that the faster temperature drop along the length. The high value of convective heat transfer in the initial phase due to which faster temperature drop takes place. Convection is found to be dominating due to less area for conduction along the length. Theoretical value and experimental value are close to each for temperature distribution as well the convective heat transfer coefficient. Efficiency is reduced in the case of hollow fin but the effectiveness of the hollow pin fin is increased by 1.76 times from an economical point of view, holoow pin fin is more efficient solution.

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