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Research Article

An experimental study on microchannel heat sink via different manifold arrangements

Anurag Dahiya1 · Mohammed Amer2  · Uzair Sajjad2 · Parismita Borah3 · Satbir Singh Sehgal4 · Harpreet Singh4

Received: 31 August 2019 / Accepted: 25 November 2019 / Published online: 6 December 2019 © Springer Nature Switzerland AG 2019

AbstractThe current experimental study performed the overall performance of the microchannel heat sink using the heat transfer coefficient, Nusselt number, and pressure drop for three novel manifold configurations. These selected manifolds have a rectangular (R), rectangle with semicircular (RSC) and divergent–convergent (DC) shapes for inlet and outlet. The heat transfer coefficient for all three types of microchannel was reported for the Reynolds number range of 342–857. The experiments were tested at four different heat inputs ranges between 50–125 W. R-type microchannel heat sink showed the worst performance, while the performance of DC-type microchannel heat sinks was the best. At Re of 342, the lowest Nusselt number was observed to be 2.8 at lower Reynolds number 342 for R-type manifold. RSC manifolds MCHS seems to be a better choice compared to R-type and DC-type MCHS with respect to pressure drop and Nusselt number. Com-pared to R-type microchannel heat sink, 24–32% and 7–10% augmentation in heat transfer coefficients were reported for DC-type and RSC-type microchannel heat sinks, respectively. Based on the released experimental results, it can be stated that DC-type microchannel heat sink is more beneficial in terms of heat transfer enhancement.

Keywords Microchannel heat sink · Heat Transfer · Reynolds Number · Pressure drop

List of symbolsAs Surface area of manifold (m2)cp Specific heat capacity (W K−1)DC Divergent–convergentDc Depth of channel (m)Dh Hydraulic diameter (m)EDM Electrical discharge machiningh Heat transfer coefficient (W m−2 K−1)h1, h2 Fluid height (m)kf Thermal conductivity of fluid (W m−1 K−1)Lt Thermal entrance length (m)LPT Liter per hourm Mass flow rate (kg s−1)MCHS Microchannel heat sinksN Number of channelsNu NUSSELT number, dimensionless

Pr Prandtl number, dimensionlessQ Heat transfer rate (W)R RectangularRe Reynold number, dimensionlessRSC Rectangle with semicircularTavg Average temperature (°C)Ti Inlet temperature (°C)Tm Mean temperature (°C)To Outlet temperature (°C)Tw Wall temperature (°C)TC Thermocouplevf Fluid velocity (m s−1)VMC Vertical milling machineWc Width of the channel

* Mohammed Amer, mohammedamer.me03g@nctu.edu.tw | 1Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu, Taiwan. 2Department of Mechanical Engineering, National Chiao Tung University, Hsinchu, Taiwan. 3Department of Petrochemical Engineering, Gurukul Vidyapeeth Institute of Engineering and Technology, Punjab, India. 4Department of Mechanical Engineering, Chandigarh University, Punjab, India.

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Greek symbolsµ Kinematic viscosity (m2 s−1)ρ Density (kg m−3)

Subscriptsavg Averagec Channelf Fluidi Inleto Outletm Means Surface

1 Background and introduction

Microchannel heat sinks are widely used in heating and cooling applications for computers, fuel cells, micro-reactors, transports, aerospace, electronics, and medical applications [1–3]. Manufacturing microchannel heat sinks (MCHS) considers as an easy operation. Basically, they are flat. Later on, they can reform and fold into classic shapes regarding the application. MCHS is lightweight if com-pared with traditional finned and tube coil. The flat chan-nels for MCHS feature a dramatically lower internal volume in a higher primary surface area compared to traditional round tubes. This will allow it to achieve higher cooling capacity with much less refrigerant. Improving the surface area to volume ratio reduces refrigerant usage up to 70% in condenser refrigerant charge. For adding energy saving, variable speed AC motors work with these microchannels coils to optimize efficiency or through adjusting speed according to the system demands and stabilizing head pressure. Moreover, the sound intensity could decrease by up to 50% compared to traditional motors. MCHS guides to less operating cost, less space used, less corro-sion resistance, and energy saving. These MCHS were first presented by Tuckerman and Pease [4]. Further investiga-tions for electronics cooling applications were conducted afterward by Garimella and Harirchian [5]. One of the main challenges for electronic devices is overheating. Overheat-ing leads to components damage, such as the integrated circuits (IC) and the computer’s CPU. Microchannel heat sinks are the major worthwhile device used to inhibit the overheating and dissipate heat from electronic devices. Traditional methods such as air cooling cannot maintain the temperature of the system within the desired tempera-ture limits due to the poor thermal conductivity and low heat capacity of gases. Here comes the role of using MCHS. Investigations for the removal of large quantities of heat using MCHS have been carried out by numerous research-ers [6–8]. However, the benefits rely on different param-eters such as uniform distribution between microchannels.

Another is proper geometric designs of microchannels, including channels size and manifold arrangements, thus guarantees better thermal performance within a reason-able range of pressure drops. There are a lot of proposed numerical and analytical models for measuring the heat transfer and pressure drop [9–11]. High-pressure drop is the major problem associated with conventional micro-channels. On the other hand, pressure is one of the marks for corrosion. Corrosion is a result of fouling happens in the internal walls [12, 13]. This one of the reasons for the need for different microchannel manifolds shapes where it can sustain longer.

Optimum geometric parameters for microchannel heat sinks with tapered channels [14] and double-lay-ered channels [15] are suggested to tackle this prob-lem. Another configuration to lower the pressure drop and intensify the heat transfer coefficient is the mani-fold microchannel originally presented by Harpole and Eninger [16] and others [17–19]. High heat fluxes dissi-pation at moderate pressure drops has been reported in single-phase operation by using manifold microchannel heat sinks [20–22]. An experimental study was carried out for investigating the impact of channel and plenum aspect ratios with different flow arrangements for vari-ous Reynolds numbers [23]. Siva et al. [24] reported a significant improvement in the flow distribution sur-rounded by the channels with a reduction in hydraulic diameter. The reason beyond this is the high-generated pressure drop through every single channel. Mohammed et al. [25] studied different shapes of microchannel like curvy, zigzag, step channel and compared them with straight and wavy channels. Lin et al. [26] performed an experimental and numerical investigation to study the heat transfer characteristics for a certain range of hydraulic diameters. From the above literature survey, it can be concluded that the geometry, plenum, and flow arrangements are important parameters to be consid-ered for the optimized performance of MCHS. Yet, further investigations for different manifold arrangements are required. Table 1 below enlists some selected literature for single-phase fluid flow in microchannel passages.

Research nowadays focuses more on details on two-phase flow and even using nanoparticle fluid flow. Utiliz-ing nanoparticles becomes one of the most popular ways in many fields such as PV/T systems [34, 35]. At the same time, it is used in the microchannel field to enhance the heat transfer coefficient and combat fouling [36–47]. This could be done through influence of the operating param-eters inside the microchannels [48]. At the same time, this research could be a hand for different fields of heat trans-fer where it could be used in plastic heat exchangers, frost-ing suppressing, or even replace some of current costly jet cooling [49–53].

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The current experimental study suggested three differ-ent fabricated shapes of manifold microchannels. These manifolds are expected to lower the pressure drop and enhance the heat transfer. Three novel MCHS are pre-sented in this study, rectangular (R) microchannel heat

sink, a rectangle with semicircular (RSC) microchannel heat sink, and divergent–convergent (DC) microchannel heat sink. These MCHS are presented and compared in terms of heat transfer coefficient and pressure drop in order to digest the most superior one. Then, it can be upgraded to use it for either single-phase or two-phase flow.

2 Experimental facility and measuring equipment

The experimental setup as shown in Fig. 1 consists of the microchannel heat sink as the main part. The MCHS is con-nected with a water pump to supply the water through the inlet of the manifold. The water pump is connected with flowmeter to control and measure the flow into the MCHS. The MCHS is connected with electric heaters at the bottom of it and controlled by a wattmeter. The wattmeter is con-trolled by a variac transformer in order to get the required heating value. At the inlet and outlet adapters, two ther-mocouples are attached to measure the temperatures. The temperatures acquired via data acquisition system. Finally, a manometer connected to the adapters is used to meas-ure the pressure drop through the microchannel.

Table 1 Selected literature for single-phase fluid flow in microchan-nel passages

Reference Re Test fluid Cross section

Tuckerman and Pease [4]

291–638 Water Rectangular

Qu and Mudawar [21]

137–1670 Water Rectangular

Peng and Petrson [19]

1530–13,455 Water Rectangular

Lee et al. [27] 300–3500 Deionized water RectangularFoli et al. [28] 100–100 – RectangularBavière et al. [29] 1–7985 Water RectangularHeris et al. [30] 50 (Al2O3/water) CircularQu et al. [31] – Water RectangularMohammed et al.

[32]100–1000 Water Rectangular

Mehendale et al. [33]

224–1121 Deionized Water Rectangular

Fig. 1 Schematic diagram of the experimental setup

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Copper was used for the fabrication of the test MCHS. The test section consists of 24 rectangular parallel micro-channels. These microchannels have a width of 0.5 mm per each channel and a 3  mm constant depth with 0.5 mm spacing between each. The hydraulic diameter of the channel is 857 μm (0.857 mm). The microchannel heat sink test section fabricated with the help of vertical milling machine (VMC) and wire cut electrical discharge machining (EDM). Inlet and outlet manifolds are fabricated through the use of the VMC machine, and the microchan-nels section was fabricated with the help of wire cut EDM machine. The high-speed steel (HSS) tool was used on the VMC machine for fabrication of manifolds. Figure 2 shows the detailed dimensions of the three tested microchannel heat sinks.

A submersible water pump was used to flow the fluid within the microchannel through inlet and outlet mani-folds. It is rated to pump 1100 L per hour (LPH) of liquid. The fluid flow rate was controlled by a microflow rotam-eter MFPN-1 LPH model with a capacity ranging from 1 to 10 LPH and an uncertainty of 2%. A control valve is used at the inlet of rotameter to allow the fine adjustment of flow rate from the pump to the inlet section. At the bottom of the channels surface area, two 1407 Beeco model car-tridge electric heaters with 150 W per each were inserted into the bore copper block for heating of microchannel heat sink during the experiment. These heaters are prop-erly insulated and connected to MECO DWM963511 model digital wattmeter with a range of 0–1150 W. The wattage was controlled by a variac transformer and the uncertainty associated with the measurement is less than 0.5%. Yet the temperature of the deionized water which is chosen as a cooling liquid at inlet/outlet adapter fitted to the inlet/outlet manifold arrangements is measured via T-type ther-mocouple (TC) with the uncertainty of ± 1 °C. Two ther-mocouples are attached to the top surface of the inlet and outlet adapters. One thermocouple is attached near the cartridge heater and the other one is at the bottom of MCHS for calculating the wall temperature. The pres-sure drop at the inlet and outlet of the manifolds is meas-ured by a U-tube differential manometer with arrange of 100–0–100 mm. The manometer ends were connected to the adapters. The difference in fluid height (h2 − h1) in the U-tube manometer is proportional to the pressure differ-ence. The results were acquired with the help of TC-800F model data acquisition system.

Fig. 2 Microchannel heat sink model

Fig. 3 Manifold arrangements, a R-type (rectangular) manifold, b RSC-type (rectangle with semicircular) manifold, c DC-type (divergent–convergent) manifold

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Fig. 4 Manifold arrangements detailed drawing, a R-type manifold, b RSC-type manifold, c DC-type manifold

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Table 2 Specifications of microchannels and acrylic screen

Item Value

Width of channels 500 µm (0.5 m)Spacing between channels 500 µm (0.5 m)Number of channels 24Base plate thickness 8 mmLength of Channels 24.5 mmDepth of channel 3 mmThickness of Acrylic Sheet 6 mmAspect ratio 6

Fig. 5 Assembly view of the available manifolds, a R-type manifold, b RSC-type manifold, c DC-type manifold

Table 3 Indicated study parameters

Item Value

Flowrate (LPH) 4, 6, 8, 10Wattages (W) 50, 75, 100, 125Base fluid Deionized waterDesign consideration R, RSC, DCNumber of experiments performed 48Flow type PerpendicularReynolds number 342–857

A transparent polycarbonate acrylic sheet was used as a cover plate to form the manifold. The acrylic sheets were fabricated with different manifold shapes as shown in Fig. 3. Figure 3a, b, c shows the isometric view of the MCHS. The acrylic cover indicates the three types of manifold arrangements rectangular (R), rectangle with semicircular (RSC), divergent–convergent (DC). Figure 4 shows the detailed drawing of the three-manifolds where the surface area was maintained the same in all mani-fold arrangements. A P-type flow arrangement has been

employed in this experiment. According to Sehgal et al. [11], in P-type flow arrangement, the fluid firstly filled the intake plenum for the starting period before it fills the whole plenum which enhances the fluid contact effect. Besides, it was observed that the minimum pressure drop was experienced in P-type flow arrangement. The specifi-cations of the MCHS and acrylic screens are presented in Table 2. After assembling the copper plate with the acrylic cover plate, a gasket maker high-temperature RTV silicone tube was used during the experiment to avoid leakage problems. Figure 5 shows the assembly view of the MCHS.

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In the current study, experimental analysis has been carried out to understand how the heat will be transfer and how the pressure difference attribute will vary with different manifold arrangements under different flow rates. For this purpose, a microchannel test piece with three different inlet and outlet manifold arrangements has been tested under four different flow rates. The test run was performed by maintaining four constant heat inputs, 50 W, 75 W, 100 W, and 125 W under the Reynolds num-ber range from 342 to 857. The pressure drop and heat dissipation capacity of single-phase MCHS were studied experimentally. The different parameters taken into con-sideration for the study have been indicated in Table 3.

3 Data reduction

The heat transfer and pressure difference consider the chief terms for overall MCHS performance. The heat is provided to the heat sink through the cartridge heaters beneath the test section. Input power supplied to heat-ers was adjusted with the help of a power variac. For steady flow, the actual heat convicted from the micro-channel to the fluid is equated to the sensible heat car-ried away by the fluid as given in Eq. (1).

where m = 𝜌 × Q and ΔT = To − Ti , To and Ti are the out-let and inlet temperatures of the fluid, respectively. These temperatures will be measured by thermocouples fitted to the top surface of the inlet and outlet adapters of the MCHS. The average of these temperatures will be taken as mean fluid temperature. Density (ρ) and specific heat capacity (cp) have been obtained on the basis of mean temperature (Tm). In case of internal flow, convective heat dissipation from the wall of channels to fluid has been cal-culated from Newton’s law of cooling as given in Eq. (2).

where Tm =Ti+To

2 (3)where h is the convective heat transfer

coefficient, As is the surface area of the channel including the surface area of inlet and outlet manifold arrangements. N is the total number of channels in the test section, and Tw is the channel wall temperature. After estimating the wall temperature, Tw, and the mean temperature Tm, the convective heat transfer coefficient has been calculated through the help of Eq. (2). The readings from the tem-perature indicator/data acquisition system and U-tube manometer have been measured when the steady-state condition. The Nusselt number has been defined as the heat dissipation capacity that represents the transfer of heat capacity of the MCHS as shown in Eq. (4):

(1)Q = mcpΔT

(2)Q = NhAsΔT

where h is the convective heat transfer coefficient, kf is the thermal conductivity of the fluid and Dh is the hydraulic diameter as defined in Eq. (5):

where Wc is the width of the channel and Dc is the depth of the channel. Reynolds number is defined as in Eq. (6):

where the inlet fluid velocity (vf ) is as given in Eq. (7):

The cross-sectional area of the channel (Ac) is given in Eq. (8):

Prandtl number is as in Eq. (9):

And the thermal entrance length is as in Eq. (10):

The physical quantity can be divided into the basic quantity and the derived quantity. The derived quantity is calculated by several basic quantities. The basic quan-tity is obtained directly by measuring the equipment and the instrument, and the error of the derived quantity is obtained through error transmission. If the derived quan-tity X is composed of n independent basic quantities, that is, X = X (x1, x2…xn), the degree of uncertainty δX of the derived quantity X is as follows:

where δx1, δx2…δxn is the degree of uncertainty of n basic quantities, and the degree of uncertainty δX of the derived quantity can be calculated by the formula (19). The follow-ing is the derived quantity discussed in this study:

The uncertainty amount of Reynolds number:

(4)Nu =hDh

kf

(5)Dh =2(Wc + Dc)

Wc + Dc

(6)Re =�vfDh

�

(7)vf =Q

NAc

(8)Ac = Wc × Dc

(9)Pr =�Cp

Kf

(10)Lt = 0.01ReDh Pr

(11)

�X =

{

[(

�X

�x1

)

�x1

]2

+

[(

�X

�x2

)

�x2

]2

+⋯ +

[(

�X

�xn

)

�xn

]2}1∕2

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The uncertainty amount of convective heat transfer coefficient:

The uncertainty amount of Reynolds number:

The uncertainty in Reynolds number, heat transfer coefficient, and Nusselt number is found to be ± 0.89%, ± 0.17%, and ± 0.99%, respectively. The overall combined uncertainties that are calculated via RSS (root-sum-square) of the bias and precision confident limits are with 95%.

4 Results and discussion

Different observations have been obtained and discussed further for comparison of different manifold arrange-ments. First, Reynolds Number effects on heat transfer, Reynolds number effects on Nusselt number, and finally the Reynolds Number effects on Pressure.

4.1 Heat transfer coefficient effect with Reynolds Number

The experiments were done at four different heat inputs 50, 75, 100, and 125 W with Reynolds number range of 342–857. Figure 6 shows the variation of the heat transfer coefficient at different Reynolds numbers with different heat inputs. At 50 W and a constant Reynolds number 342, it was observed that the maximum heat transfer coeffi-cient was in DC-type manifold MCHS followed by RSC- and R-type. As the Reynolds number increases from 342 to 857, the increasing percentage in the heat transfer coefficient was between 24 and 33%.

Similar results were observed at a heat input of 75, 100, and 125 W. The increasing percentage of DC-type manifold MCHS was observed to be between 24 and 33%. The mini-mum fluid retention time was in the case of R-type mani-fold MCHS. With less retention time, the fluid is not able to get proper heat from MCHS which affects the heat trans-fer coefficient. In the DC-type manifold MCHS, fluid travel the maximum distance and have maximum retention time. This leads to the highest heat transfer coefficient. In

(12)

�Re

Re=

[

(

��

�

)2

+

(

�vf

vf

)2

+

(

�Dh

Dh

)2

+

(

��

�

)2]1∕2

(13)�h

h=

[

(

�Q

Q

)2

+

(

�As

As

)2

+

(

�(ΔT )

ΔT

)2]1∕2

(14)�Nu

Nu=

[

(

�h

h

)2

+

(

�Dh

Dh

)2

+

(

�kf

kf

)2]1∕2

RCS-type manifold, the retention time is less than DC-type but more than R manifold.

4.2 Nusselt Number effect with Reynolds Number

Figure  7 shows the variation of experimental Nusselt number at different heat inputs 50, 75, 100, and 125 W. At constant Reynolds number, the maximum Nusselt number was observed on the DC-type manifold MCHS, followed by

Fig. 6 Comparison of MCHS with the different manifold arrange-ment at different Reynolds numbers at the heat transfer coefficient with different heat input

Fig. 7 Reynolds number vs. Nusselt number comparison for differ-ent manifolds arrangements

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5 Conclusions

The current study showed an experimental investigation of the thermo-hydraulic performance of MCHS for three different types of manifold arrangements was made at a constant aspect ratio of 6. The manifolds have a rectan-gular (R), rectangle with semicircular (RSC) and diver-gent–convergent (DC) shapes. The experiments were done at four different heat inputs 50, 75, 100, and 125 W under Reynolds number of 342–857. The following conclu-sions are recorded:

1. Compared to R-type MCHS, 24–32% and 7–10% higher heat transfer coefficients were noted for DC-type and RSC-type MCHS, respectively, for Reynolds number ranging 342–857.

2. At different heat inputs ranging from 50 to 125 W, the maximum Nusselt number was observed for DC-type MCHS compared to R-type and RSC-type MCHS. The lowest Nusselt number was observed to be 2.8 at lower Reynolds number 342 for R-type manifold.

3. More pressure drop was observed in DC-type MCHS compared to R-type and RSC-type MCHS.

From the practical application point of view, the RSC manifolds MCHS seems to be a better choice compared to R-type and DC-type MCHS with respect to pressure drop and Nusselt number.

Acknowledgements The authors would like to express their gratitude with pearls of wisdom for the support provided by Chandigarh Uni-versity in India.

Compliance with ethical standards

Conflict of interest The authors declare that they have no conflict of interest.

Fig. 8 Reynolds number vs. pressure drop comparison for different manifolds arrangements

RSC and R-type manifold MCHS. The lowest Nusselt num-ber was observed to be 2.8 at lower Reynolds number 342.

4.3 Pressure drop effect with Reynolds Number

Figure 8 represents the variations of the pressure drop as a function of Reynolds number for three different manifold arrangements. The reason beyond the variation of pres-sure is that as the fluid velocity increases, wall shear stress within microchannels also increases, resulting in a higher pressure drop. Maximum pressure drop is experienced in DC-type manifold MCHS followed by RSC and R-type manifold MCHS. The thermal entrance length range is in the range of 2.21–5.54 mm at varies Reynolds numbers. The fluid flow travel length between the inlet and outlet plenum of the MCHS for RSC (82.9 mm) flow arrangement was more as compared to DC (76.1 mm) and R (74.5 mm). The retention time taken by deionized water flowing from inlet to outlet manifold was the least in R-type manifold followed by RSC and DC.

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References

1. Morini GL (2004) Single-phase convective heat transfer in microchannels: a review of experimental results. Int J Therm Sci 43:631–651

2. Mohammed H, Bhaskaran G, Shuaib N, Saidur R (2011) Heat transfer and fluid flow characteristics in microchannels heat exchanger using nanofluids: a review. Renew Sustain Energy Rev 15:1502–1512

3. Rostami A, Mujumdar A, Saniei N (2002) Flow and heat transfer for gas flowing in microchannels: a review. Heat Mass Transf 38:359–367

4. Tuckerman DB, Pease RFW (1981) High-performance heat sink-ing for VLSI. IEEE Electron Device Lett 2:126–129

5. Garimella SV, Harirchian T (2013) Microchannel heat sinks for electronics cooling, the encyclopedia of thermal packaging, vol 1. World Scientific, Singapore, p 248

6. Faulkner D, Khotan M, Shekarriz R (2003) Practical design of a 1000 W/cm2 cooling system. In: 19th IEEE SEMI-THERM symposium

7. Lee J, Mudawar I (2005) Two-phase flow in high-heat flux micro-channel heat sink for refrigeration cooling applications: part I—pressure drop characteristics. Int J Heat Mass Transf 48:941–955

8. Lee J, Mudawar I (2005) Two-phase flow in high-heat flux micro-channel heat sink for refrigeration cooling applications: part II—heat transfer characteristics. Int J Heat Mass Transf 48:941–955

9. Vafai K, Zhu L (1999) Analysis of two-layered microchannel heat sink concept in electronic cooling. Int J Heat Mass Transf 42:2287–2297

10. Ryu JH, Choi DH, Kim SJ (2002) Numerical optimization of the thermal performance of a microchannel heat sink. Int J Heat Mass Transf 45:2823–2827

11. Lee PS, Garimella SV (2006) Thermally developing flow and heat transfer in rectangular microchannels of different aspect ratios. Int J Heat Mass Transf 49(17):3060–3067

12. Mueller-Steinhagen H (2000) Heat exchanger fouling: mitigation and cleaning technologies. IChemE-technology and engineer-ing hand book

13. Bott TR (1995) Fouling of heat exchangers. Elsevier, Amsterdam 14. Hung TC, Yan WM (2012) Optimization of a microchannel heat

sink with varying channel heights and widths. Numer Heat Transf Part A 62:722–741

15. Hung TC, Yan WM, Wang XD, Huang YX (2012) Optimal design of geometric parameters of double-layered microchannel heat sinks. Int J Heat Mass Transf 55:3262–3272

16. Harpole GM, Eninger JE (1991) Micro-channel heat exchanger optimization. In: Proceedings of the seventh IEEE semiconduc-tor thermal measurement and management, symposium, pp 59–63

17. Nguyen CT, Roy G, Gauthier C, Galanis N (2007) Heat transfer enhancement using Al2O3–water nanofluid for an electronic liquid cooling system. Appl Therm Eng 27:1501–1506

18. Wang X-Q, Mujumdar AS (2008) A review on nanofluids-part II: experiments and applications. Braz J Chem Eng 25:631–648

19. Peng X, Peterson G (1996) Convective heat transfer and flow fric-tion for water flow in microchannel structures. Int J Heat Mass Transf 39:2599–2608

20. Escher W, Michel B, Poulikakos D (2010) A novel high perfor-mance, ultra-thin heat sink for electronics. Int J Heat Fluid Flow 31(4):586–598

21. Kermani E et al (2009) Experimental investigation of heat trans-fer performance of a manifold microchannel heat sink for cool-ing of concentrated solar cells. In: Proceedings of the electronics components technology conference, San Diego, CA, pp 453–459

22. Sharma CS et al (2015) A novel method of energy efficient hotspot-targeted embedded liquid cooling for electronics: an experimental study. Int J Heat Mass Transf 88:684–694

23. Sehgal SS et al (2012) Effect of channel and plenum aspect ratios on the performance of micro-channel heat sink under different flow arrangements. J Mech Sci Technol 26(9):2985–2994

24. Siva VM et al (2014) Effect of flow maldistribution on the thermal performance of parallel micro-channel cooling systems. Int J Heat Mass Transf 73:424–428

25. Mohammed HA, Gunnasegaran P, Shuaib NH (2011) Influence of channel shape on the thermal and hydraulic performance of microchannel heat sink. Int Commun Heat Mass Transf 38:474–480

26. Qu WL, Mudawar I (2002) Experimental and numerical study of pressure drop and heat transfer in a single-phase micro-channel heat sink. Int J Heat Mass Transf 45:2549–2565

27. Lee PS, Garimella SV, Liu D (2005) Investigation of heat trans-fer in rectangular micro-channels. Int J Heat Mass Transf 48:1688–1704

28. Foli K, Okaba T, Olhofer M, Jon Y, Sendhoff B (2006) Optimiza-tion of micro heat exchanger: CFD, analytical approach and multi-objective evolutionary algorithms. Int J Heat Mass Transf 49:1090–1099

29. Bavière R et al (2006) Bias effects on heat transfer measurements in microchannel flows. Int J Heat Mass Transf 49:3325–3337

30. Heris SZ, Esfahany MN, Etemad SG (2007) Experimental investi-gation of convective heat transfer of Al2O3/water nanofluids in circular tube. Int J Heat Fluid Flow 28:203–210

31. Qu W et al (2000) Heat transfer for water flow in trapezoidal silicon microchannels. Int J Heat Mass Transf 43:3925–3936

32. Mohammed HA, Gunnasegaran P, Shuaib NH (2011) Influence of various base nanofluids and substrate materials on heat transfer in trapezoidal microchannel heat sinks. Int Commun Heat Mass Transf 38:194–201

33. Mehendale SS, Jacobi AM, Shah RK (2000) Fluid flow and heat transfer at micro and meso-scales with application to heat exchanger design. Appl Mech Rev 53:175–193

34. Abbas N, Awan MB, Amer M et al (2019) Applications of nano-fluids in photovoltaic thermal systems: a review of recent advances. Phys A Stat Mech Appl 536:122513. https ://doi.org/10.1016/j.physa .2019.12251 3

35. Sajjad U, Amer M, Ali HM, Dahiya A, Abbas N (2019) Cost effec-tive cooling of photovoltaic modules to improve efficiency. Case Stud Therm Eng 14:100420. https ://doi.org/10.1016/j.csite .2019.10042 0

36. Sarafraz MM et al (2017) Low-frequency vibration for fouling mitigation and intensification of thermal performance of a plate heat exchanger working with CuO/water nanofluid. Appl Therm Eng. https ://doi.org/10.1016/j.applt herma leng.2017.04.083

37. Salari E et al (2016) Boiling heat transfer of alumina nano-fluids: role of nanoparticle deposition on the boiling heat transfer coefficient. Period Polytech Chem Eng 60:252–258. https ://doi.org/10.3311/PPch.9324

38. Arya A et al (2018) Thermal performance analysis of a flat heat pipe working with carbon nanotube-water nanofluid for cooling of a high heat flux heater. Heat Mass Transf 54:985–997

39. Sarafraz MM, Arjomandi M et al (2019) Experimental thermal energy assessment of a liquid metal eutectic in a microchannel heat exchanger equipped with a (10 Hz/50 Hz) resonator. Appl Therm Eng 148:578–590. https ://doi.org/10.1016/j.applt herma leng.2018.11.073

40. Sarafraz MM, Arya H, Arjomandi M (2018) Thermal and hydrau-lic analysis of a rectangular microchannel with gallium-copper oxide nano-suspension. J Mol Liq. https ://doi.org/10.1016/j.molli q.2018.05.026

RETRACTED ARTIC

LE

Vol.:(0123456789)

SN Applied Sciences (2020) 2:40 | https://doi.org/10.1007/s42452-019-1784-6 Research Article

41. Sarafraz MM, Arjomandi M (2018) Thermal performance analy-sis of a microchannel heat sink cooling with copper oxide-indium (CuO/In) nano-suspensions at high-temperatures. Appl Therm Eng 137:700–709. https ://doi.org/10.1016/j.applt herma leng.2018.04.024

42. Sarafraz MM, Arjomandi M (2018) Demonstration of plausible application of gallium nano-suspension in microchannel solar thermal receiver: experimental assessment of thermo- hydrau-lic performance of microchannel. Int Commun Heat Mass Transf 94:39–46. https ://doi.org/10.1016/j.ichea tmass trans fer.2018.03.013

43. Sarafraz MM et al (2017) Fouling formation and thermal perfor-mance of aqueous carbon nanotube nanofluid in a heat sink with rectangular parallel microchannel. Appl Therm Eng 123:29–39. https ://doi.org/10.1016/j.applt herma leng.2017.05.056

44. Nikkhah V, Sarafraz MM, Hormozi F (2015) Application of spheri-cal copper oxide (II) water nano-fluid as a potential coolant in a boiling annular heat exchanger. Chem Biochem Eng Q 29:405–415. https ://doi.org/10.15255 /CABEQ .2014.2069

45. Sarafraz MM et  al (2018) Thermal performance of a heat sink microchannel working with biologically produced sil-ver-water nano fluid: experimental assessment. Exp Therm Fluid Sci 91:509–519. https ://doi.org/10.1016/j.expth ermfl usci.2017.11.007

46. Lee J, Mudawar I (2007) Assessment of the effectiveness of nanofluids for single-phase and two-phase heat transfer in micro-channels. Int J Heat Mass Transf 50:452–463. https ://doi.org/10.1016/j.ijhea tmass trans fer.2006.08.001

47. Ammar S et al (2019) Condensing heat transfer coefficients of R134a in smooth and grooved multiport flat tubes of

automotive heat exchanger: an experimental investigation. Int J Heat Mass Transf 134:366–376

48. Sajawal M, et al. (2019) Experimental thermal performance analysis of finned tube-phase change material based double pass solar air heater. Case Stud Therm Eng 100543

49. Amer M et  al (2019) Experiments for suitability of plastic heat exchangers for dehumidification applications. Appl Therm Eng 158:113827. https ://doi.org/10.1016/j.applt herma leng.2019.11382 7

50. Amer M, Wang CC (2017) Review of defrosting methods. Renew Sustain Energy Rev 73:53–74. https ://doi.org/10.1016/j.rser.2017.01.120

51. Amer M et  al (2018) An experimental study of plastic heat exchangers applicable for dehumidification. Int Heat Transf Conf Digit Libr. https ://doi.org/10.1615/IHTC1 6.her.02116 5

52. Ullah H, Hussain M, Abbas N, Ahmad H, Amer M, Noman M (2019) Numerical investigation of modal and fatigue perfor-manceof a horizontal axis tidal current turbine using fluid-structure interaction. J Ocean Eng Sci. https ://doi.org/10.1016/j.joes.2019.05.008

53. Chu W, Huang K, Amer M, Wang CC (2019) Experimental and numerical investigations on jet impingement cooling for elec-tronic modules. J Heat Transf. https ://doi.org/10.1115/1.40441 49

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