复合纳米流体在歧管微通道内的流动传热数值模拟

doi:10.12068/j.issn.1005-3026.2024.07.007

摘要/Abstract

摘要：

对歧管微通道散热器中复合纳米流体的流动与传热特性进行数值模拟.以水基Al₂O₃-CuO复合纳米流体为工质，探讨纳米颗粒混合比例、体积分数（φ）、雷诺数（Re）以及引入凹槽对散热器流动换热的影响.结果表明，复合纳米流体在较高的体积分数和雷诺数下具有较好的热力学性能，但相应的压降也会增大.混合比例1∶4的复合纳米流体整体性能最优，在Re=100，φ=6%时，泵功消耗比单一的水基Al₂O₃纳米流体降低18.9%，综合性能指标提高21.7%.在歧管微通道的侧壁上添加不同形状的凹槽与光滑歧管微通道的换热效果基本相当.

关键词: 歧管微通道散热器, 复合纳米流体, 凹槽结构, 流动与传热

Abstract:

The numerical simulation of flow and heat transfer characteristics of hybrid nanofluids in a manifold microchannel heat sink （MMHS） was performed. Using Al₂O₃-CuO-water as the working fluid， the effects of the mixing ratio of nanoparticles， volume fraction （φ）， Reynolds number （Re）， and the introduction of grooves on the flow and heat transfer of the heat sink were investigated. The results showed that the hybrid nanofluids have excellent thermodynamic properties at high concentrations and Re， but the corresponding pressure drop increases. The overall performance of the hybrid nanofluids with a mixing ratio of 1∶4 is the best. When Re=100， φ=6%， the pump power consumption is 18.9% lower， and the overall performance index is 21.7% higher than that of single Al₂O₃-water nanofluids. Adding different shapes of grooves on the sidewall has a similar heat transfer effect to that of a smooth bifurcation microchannel.

Key words: manifold microchannel heat sink, hybrid nanofluid, grooved structure, flow and heat transfer

中图分类号:

TK 124

董辉, 于珂凡, 赵亮, 王进. 复合纳米流体在歧管微通道内的流动传热数值模拟[J]. 东北大学学报（自然科学版）, 2024, 45(7): 960-966.

Hui DONG, Ke-fan YU, Liang ZHAO, Jin WANG. Numerical Simulation of Flow and Heat Transfer of Hybrid Nanofluids in Manifold Microchannel Heat Sink[J]. Journal of Northeastern University(Natural Science), 2024, 45(7): 960-966.

图/表 13

图1 歧管微通道散热器几何模型（a）—计算模型；（b）—单元模型；（c）—凹槽形状.

Fig.1 Geometric model of manifold microchannel heat sink

表1 MMHS几何参数 (μm)

Table 1 MMHS geometric parameters

L_i	L_o	L_c	L_n	L_d	L_a	W_r	W_f	W_c	H_c	H_m	H_s
1 000	2 000	8 000	1 000	490	108	31	100	160	1 500	1 000	1 000

表2 Al2O3和CuO热物理性质

Table 2 Thermophysical properties of Al2O3 and CuO

参数	Al₂O₃	CuO
密度/（kg·m^-3）	3 970	6 500
热导率/（W·m^-1·K^-1）	40	20
比热容/（J·kg^-1·K^-1）	765	535.6

表3 根据文献[25]实验设计β的曲线拟合关系

Table 3 Curve fitting relationship of β designed according to Ref.[25] experiments

纳米颗粒	β	体积分数	温度/K
Al₂O₃	8.440 7(100φ)^{-1.073 04}	1%≤φ≤10%	298≤T≤363
CuO	9.881(100φ)^{-0.944 6}	1%≤φ≤6%	298≤T≤363

表4 网格独立性测试结果

Table 4 Grid independence test results

编号	网格单元数	$T h ˉ$ /K	相对误差/%	T_out/K	误差/%
1	87 961	322.767 9	—	302.780 4	—
2	651 738	322.260 8	0.157 36	303.161 4	0.125 68
3	727 947	322.002 8	0.080 12	303.246 8	0.028 16
4	1 050 160	322.000 2	0.000 81	303.244 6	0.000 73

表4 网格独立性测试结果

Table 4 Grid independence test results

编号	网格单元数	$T h ˉ$ /K	相对误差/%	T_out/K	误差/%
1	87 961	322.767 9	—	302.780 4	—
2	651 738	322.260 8	0.157 36	303.161 4	0.125 68
3	727 947	322.002 8	0.080 12	303.246 8	0.028 16
4	1 050 160	322.000 2	0.000 81	303.244 6	0.000 73

图2 数值模拟与Sharma等[27]实验结果偏差

Fig.2 Deviation between numerical simulation and the experimental data from Sharma et al[27].

图3 不同雷诺数下流体的速度分布（a）—Re=25；（b）—Re=50；（c）—Re=75；（d）—Re=100.

Fig.3 Velocity distribution of fluid at different Re

图4 不同体积分数和混合比例下MMHS温度梯度（a）—φ=0.02，a∶c=1∶4；（b）—φ=0.02，a∶c=1∶1；（c）—φ=0.02，a∶c=4∶1；（d）—φ=0.06，a∶c=4∶1.

Fig.4 MMHS temperature graduation with different volume fraction and mixing ratio

图5 受热面热点温度

Fig.5 Hot spot temperature of heating surface

图6 不同体积分数和混合比例对泵功率的影响

Fig.6 Effects of different volume fraction and mixing ratio on pump power

图7 体积分数和混合比例对综合性能的影响

Fig.7 Effects of volume fraction and mixing ratio on the overall performance

图8 凹槽形状对热点温度的影响

Fig.8 Effect of groove shape on hot spot temperature

图9 凹槽形状对综合性能指标的影响

Fig.9 Effect of groove shape on overall performance index

参考文献 27

1	He Z Q， Yan Y F， Zhang Z E.Thermal management and temperature uniformity enhancement of electronic devices by micro heat sinks：a review［J］.Energy，2021，216：119223.
2	Khattak Z， Ali H M.Air cooled heat sink geometries subjected to forced flow：a critical review［J］.International Journal of Heat and Mass Transfer，2019，130：141-161.
3	Harpole G M， Eninger J E.Micro‑channel heat exchanger optimization［C］// Proceedings of Seventh Annual IEEE，Semiconductor Thermal Measurement and Management Symposium. Phoenix，1991：59-63.
4	Ryu J H， Choi D H， Kim S J.Three‑dimensional numerical optimization of a manifold microchannel heat sink［J］.International Journal of Heat and Mass Transfer，2003，46（9）：1553-1562.
5	Luo Y， Zhang J Z， Li W.A comparative numerical study on two‑phase boiling fluid flow and heat transfer in the microchannel heat sink with different manifold arrangements［J］.International Journal of Heat and Mass Transfer，2020，156：119864.
6	Sajid M U， Ali H M.Thermal conductivity of hybrid nanofluids：a critical review［J］.International Journal of Heat and Mass Transfer，2018，126：211-234.
7	Choi S， Eastman J A.Enhancing thermal conductivity of fluid with nanoparticles［C］// AMSE International Mechanical Engineering Congress and Exposition.San Francisco，CA，1995：12-17.
8	Motlagh S Y， Golab E， Sadr A N.Two‑phase modeling of the free convection of nanofluid inside the inclined porous semiannulus enclosure［J］.International Journal of Mechanical Sciences，2019，164：105183.
9	Aminian E， Moghadasi H， Saffari H.Magnetic field effects on forced convection flow of a hybrid nanofluid in a Q15 cylinder filled with porous media：a numerical study［J］.Journal of Thermal Analysis and Calorimetry，2020，141（5）：1-13.
10	Yue Y， Mohammadian S， Zhang Y W.Analysis of performances of a manifold microchannel heat sink with nanofluids［J］.International Journal of Thermal Sciences，2015，89：305-313.
11	Pourfattah F， Arani A， Babaie M R，et al.On the thermal characteristics of a manifold microchannel heat sink subjected to nanofluid using two‑phase flow simulation［J］.International Journal of Heat and Mass Transfer，2019，143：118518.
12	Adio S A， Olalere A E， Olagoke R O，et al.Thermal and entropy analysis of a manifold microchannel heat sink operating on CuO‑water nanofluid［J］.Journal of the Brazilian Society of Mechanical Sciences and Engineering，2021，43（2）：1-15.
13	Zhu Q F， Su R R， Hu L Y，et al.Heat transfer enhancement for microchannel heat sink by strengthening fluids mixing with backward right‑angled trapezoidal grooves in channel sidewalls［J］.International Communications in Heat and Mass Transfer，2022，135：106106.
14	Zhu Q F， Xia H X， Chen J J，et al.Fluid flow and heat transfer characteristics of microchannel heat sinks with different groove shapes［J］.International Journal of Thermal Sciences，2021，161：106721.
15	Kuppusamy N R， Mohammed H A， Lim C W.Numerical investigation of trapezoidal grooved microchannel heat sink using nanofluids［J］.Thermochimica Acta，2013，573：39-56.
16	Wang R J， Wang W， Wang J W，et al.Analysis and optimization of trapezoidal grooved microchannel heat sink using nanofluids in a micro solar cell［J］.Entropy，2018，20（1）：e20010009.
17	Garcia de Maria J M， Bairi A， Zarco‑Pernia E.A review on natural convection in enclosures for engineering applications，the particular case of the parallelogrammic diode cavity［J］.Applied Thermal Engineering，2014，63：304-322.
18	Al‑Rashed A A A A， Amin S， Sajad E，et al.Numerical investigation of non‑Newtonian water‑CMC/CuO nanofluid flow in an offset strip‑fin microchannel heat sink：thermal performance and thermodynamic considerations［J］.Applied Thermal Engineering，2019，155：247-258.
19	Tohidi A， Ghaffari H， Nasibi H，et al.Heat transfer enhancement by combination of chaotic advection and nanofluids flow in helically coiled tube［J］.Applied Thermal Engineering Design Processes Equipment Economics，2015，86：91-105.
20	Kong D Y， Kim Y S， Kang M S，et al.A holistic approach to thermal‑hydraulic design of 3D manifold microchannel heat sinks for energy‑efficient cooling［J］.Case Studies in Thermal Engineering，2021，28：101583.
21	Alfaryjat A A， Mohammed H A， Adam N M，et al.Numerical investigation of heat transfer enhancement using various nanofluids in hexagonal microchannel heat sink［J］.Thermal Science and Engineering Progress，2018，5：252-262.
22	Jiang Y N， Zhou X M， Wang Y.Comprehensive heat transfer performance analysis of nanofluid mixed forced and thermocapillary convection around a gas bubble in minichannel［J］.International Communications in Heat and Mass Transfer，2020，110：104386.
23	Zhou S Q， Ni R.Measurement of the specific heat capacity of water‑based Al₂O₃ nanofluid［J］.Applied Physics Letters，2008，92：093123.
24	Koo J， Kleinstreuer C.A new thermal conductivity model for nanofluids［J］.Journal of Nanoparticle Research，2004，6（6）：577-588.
25	Vajjha R S， Das D K.Experimental determination of thermal conductivity of three nanofluids and development of new correlations［J］.International Journal of Heat and Mass Transfer，2009，52（21/22）：4675-4682.
26	Corcione M.Heat transfer features of buoyancy‑driven nanofluids inside rectangular enclosures differentially heated at the sidewalls［J］.International Journal of Thermal Sciences，2010，49（9）：1536-1546.
27	Sharma C S， Zimmermann S， Tiwari M K，et al.Optimal thermal operation of liquid‑cooled electronic chips［J］.International Journal of Heat and Mass Transfer，2012，55：1957-1969.