Thermal Performance of Triangular Folded Fin Heat Sinks in a Duct

2003 ◽  
Author(s):  
Seo Young Kim ◽  
Taeho Ji ◽  
Dong Gyu Choi ◽  
Byung Ha Kang

Experiments have been carried out to investigate the convective heat transfer characteristics from triangular folded fin heat sinks in a suction-type fan duct. The dimension of the triangular folded fin heat sinks is 62 mm in height with a 12 mm thick base plate, 292 mm in width, and 447 mm in length. The inlet flow velocity is varied in the range of 0.6–5.3 m/s. Thermal performance of triangular folded fin heat sinks is evaluated in terms of thermal resistance of heat sinks according to flow velocity and fan power. The results obtained show that the present triangular folded-fin heat sink shows a higher thermal performance compared to a conventional extruded plate-fin heat sink. Especially, a perforated slit folded-fin heat sink displays a lower thermal resistance. As the number of slit fabricated on the perforated folded fins increases, thermal performance is more pronounced.

2007 ◽  
Vol 129 (4) ◽  
pp. 518-521 ◽  
Author(s):  
Gaowei Xu ◽  
Yingjun Cheng ◽  
Le Luo

The heat-transfer characteristics of 128 small-sized plate-fin heat sinks in a supercomputer chassis are investigated with CFD simulation. The V-shaped curves of the chip temperature versus fin pitch and fin thickness are derived and a thermal resistance model is built to explore the profile and obtain the convective heat-transfer coefficient of the heat sinks. It turns out that the V-shaped profile arises from the joint action of the thermal conduction and convection of heat sink, which can be attributed to the intricacy of the dependencies of thermal resistances on either fin pitch or thickness. It can be further concluded that Biot criterion is applicable to estimate the Biot number of large-scale plate-fin heat sink but not applicable for the small-sized one. The convective heat-transfer coefficient is a complicated function of fin pitch and fin thickness. The empirical formulas of heat transfer are obtained and the fin pitch and fin thickness are optimized.


2021 ◽  
pp. 243-243
Author(s):  
Periyannan Lakshmanan ◽  
Saravanan Periyasamy ◽  
Mohan Raman

Experimental research demonstrates the performance of electronic devices on plate fin heat sinks in order to guarantee that operating temperatures are kept as low as possible for reliability. Paraffin wax (PCM) is a substance that is used to store energy and the aluminum plate fin cavity base is chosen as a Thermal Conductivity Enhancer (TCEs). The effects of PCM material (Phase shift material), cavity form base (Rectangular, Triangular, Concave and Convex) with PCM, Reynolds number (Re= 4000-20000) on heat transfer effectiveness of plate fin heat sinks were experimentally explored in this research. The thermal performance of concave base plate fin heat sink with PCM is increased up to 7.8% compared to other cavity base heat sinks.


Author(s):  
T. Y. Wu ◽  
M. C. Wu ◽  
J. T. Horng ◽  
S. F. Chang ◽  
P. L. Chen ◽  
...  

A series of experimental studies on the heat transfer characteristics from heat sinks or Heat Sink/TEC assemblies in a ducted flow have been performed. Their effects on heat transfer characteristics in ducted flow have been systematically explored. From the results, new performance correlations of the temperature difference (ΔT) and terminal voltage (V) of the TEC modules are proposed. Besides, two new correlations of steady-state average Nusselt number and external thermal resistance in terms of relevant influencing parameters for confined ppf heat sinks in a ducted flow are also proposed, respectively. The statistical sensitivity analysis of ANOVA F-test is employed to estimate the contributions of relevant parameters. Furthermore, a series of RSM models for evaluating heat transfer characteristics including average Nusselt number, average external thermal resistance and Tc−Ta are established. A Sequential Quadratic Programming with multi-starting-point method is successfully employed to automatically and efficiently seek a globally optimal thermal performance. An optimal design of HS/TEC assemblies under both COP ≥ 2 and pumping power limitation larger than 30 W can be achieved with a reduction of 75% on thermal resistance.


Author(s):  
K Bala Subrahmanyam ◽  
Pritam Das ◽  
Aparesh Datta

In the present study, a detailed numerical simulations of liquid flow in microchannel heat sink with four different geometry of ribs: rectangular (RR), backward triangular (BTR), forward triangular (FTR) and diamond (DR) arranged symmetrically inside reentrant fan shaped cavities (FC) on side walls has been conducted and compared with smooth channel (SC) to acquire fluid flow and heat transfer characteristics between Reynolds numbers of 136−588. The local pressure, temperature and heat transfer coefficients were determined to understand the convective heat transfer regimes and to analyze local flow behavior. The three-dimensional conjugate heat transfer model, investigation is done extensively to identify the influence of geometrical parameters towards augmenting thermal performance with parametric optimization. Evolved governing equations are solved by using SIMPLEC algorithm. Attempt has been made to improve heat extraction ability with reasonable pressure drop by replacing the existing simple design of microsink. It is observed that Nusselt number and friction factor are in good agreement with previous experimental data. Based on detailed parametric study, it was found that FC-RR is good in achieving maximum Nusselt number, but due to higher pressure drop penalty giving lower performance. Out of four proposed, FC-DR is conferring upstanding balance between heat transfer, pressure drop and giving the best thermal performance of 1.97 at Re = 391.47.


Author(s):  
Hung-Yi Li ◽  
Ming-Hung Chiang ◽  
Chih-I Lee ◽  
Wen-Jei Yang

This work experimentally studies the thermal performance of plate-fin vapor chamber heat sinks using infrared thermography. The effects of the fin width, the fin height and the Reynolds number on the thermal performance are considered. The results show that generated heat is transferred more uniformly to the base plate by a vapor chamber heat sink than by a similar aluminum heat sink. Therefore, the maximum temperature is effectively reduced. The overall thermal resistance of the vapor chamber heat sink declines as the Reynolds number increases, but the strength of the effect falls. The effect of the fin dimensions on the thermal performance is stronger at a lower Reynolds number.


2017 ◽  
Vol 139 (5) ◽  
Author(s):  
Yongtong Li ◽  
Liang Gong ◽  
Minghai Xu ◽  
Yogendra Joshi

The present study presents a concept of biporous metal foam heat sink applicable to electronic cooling. This heat sink has two metal foam layers arranged in parallel along the primary flow direction, with different metal foam thickness, porosity, and pore density for each layer. The forced convective heat transfer in biporous metal foam heat sink is numerically investigated by employing the Forchheimer–Brinkman extended Darcy momentum equation and local thermal nonequilibrium energy equation. The effects of geometrical and morphological parameters on thermal and hydraulic performance are discussed in detail, and the heat transfer enhancement mechanism of biporous metal foam is analyzed. The thermal performance of biporous metal foam heat sink is compared with that of uniform metal foam heat sink. The results show that the thermal resistance of the biporous metal foam heat sink decreases with decrease of top layer metal foam porosity at a fixed bottom metal foam porosity of 0.9. It is seen that the biporous metal foam heat sink can outperform the uniform metal foam heat sink with a proper selection of foam geometrical and morphological parameters, which is attributed to the presence of high velocity gradient at the boundary layer that can enhance the convective heat transfer. The best observed thermal performance of biporous metal foam heat sink is achieved by employing 30 pores per inch (PPI) metal foam at the bottom layer, with a fixed 50 PPI metal foam at the top layer for the porosities of both layers equal to 0.9, and the optimal thickness of the bottom foam layer is about 1 mm.


Author(s):  
M. P. Wang ◽  
H. T. Chen ◽  
J. T. Horng ◽  
T. Y. Wu ◽  
P. L. Chen ◽  
...  

An effective method for predicting the optimal thermal performance of partially-confined compact heat sinks under multi-constraints of pressure drop and heat sink mass has been successfully developed. The design variables of PPF compact heat sinks include: heat sink fin and base material, thickness of heat sink base, heat flux, channel top bypass and inlet flow velocity. A total of 108 experimental cases for confined forced convection are designed by the Central Composite Design (CCD) method. According to the results in ANOVA, a sensitivity analysis for the design factors is performed. From the analysis, the effect of inlet flow velocity, which has the contribution percentage of 86.24%, dominates the thermal performance. The accuracies of the quadratic RSM models for both thermal resistance and pressure drop have been verified by comparing the predicted response values to the actual experimental data. The maximum deviations of thermal resistance and pressure drop are 9.41% and 7.20% respectively. The Response Surface Methodology is applied to establish analytical models of the thermal resistance and pressure drop constraints in terms of the key design factors with a CCD experimental design. By employing the Sequential Quadratic Programming technique, a series of constrained optimal designs can be efficiently performed. The numerical optimization results for four cases under different constraints are obtained, and the comparisons between these predicted optimal designs and those measured by the experimental data are made with a satisfactory agreement.


Sign in / Sign up

Export Citation Format

Share Document