粒径混合比对Al2O3/水纳米流体传热性能影响及评价

doi:10.16085/j.issn.1000-6613.2019-0326

摘要/Abstract

摘要：

采用两步法制备体积分数为0.5%和1.0%的Al₂O₃/水纳米流体，研究20nm和50nm Al₂O₃纳米粒子的混合比对热导率和黏度的影响，并用c _μ/c _λ和Mo数来评价其综合传热效果，判断是否适用于实际传热过程。实验结果表明，有效热导率和相对黏度受团聚体尺寸影响较大。在体积分数为1.0%和混合比为50∶50时有效热导率的增幅最大，而混合比为（40∶60）～（60∶40）之间，相对黏度最低。这是因为此时团聚体的尺寸小，相应地沉淀速度慢，说明其分散性较好，形成局部粒子富集区，即“50nm固体粒子-20nm固体粒子-液体分子”的界面层，能产生高导热渗透通道及低热阻区，使热导率增大。在层流时，该纳米流体适用于实际传热过程中的范围为：体积分数0.5%和1.0%，混合比40∶60和50∶50，温度25～50℃。在紊流时，体积分数为0.5%和温度高于40℃时，混合比范围为(40∶60)～(60∶40)才适合使用此纳米流体。

关键词: 纳米流体, 热导率, 黏度, 团聚体尺寸, 混合比

Abstract:

A two-step method was used to prepare Al₂O₃/water of nanofluids at mass fraction of 0.5% and 1.0%. This work focuses on the effect of mixture ratio of 20nm and 50nm Al₂O₃ nanoparticles on the thermal conductivity and viscosity. Moreover, the comprehensive heat transfer of Al₂O₃/water of nanofluids was estimated by c _μ/c _λ and Mo in the real heat transfer process. The experimental results showed that the effect of the cluster size on effective thermal conductivity and viscosity is obvious. Al₂O₃/water of nanofluids with mass fraction of 1.0% and mixture ratio of 50∶50 exhibited the largest enhancement of effective thermal conductivity while the relative viscosity was the lowest with mixture ratio from 40∶60 to 60∶40. The reason is that the smaller clustering size of order enables nanofluids to reduce sedimentation rate indicating the dispersion of nanofluids. Thus, the formation of a localized particle-rich zone creates high-conductive percolation path of lesser thermal resistance compared to a particle-free zone, which forms “50nm-20nm-liquid layered structure” and results in enhancing thermal conductivity. Lastly, the suitable areas for nanofluids applied in laminar flow were the temperature range from 25℃ to 50℃ and mixture ratio of 40∶60 and 50∶50 at mass fraction of 0.5 % and 1.0%. Moreover, the suitable areas for nanofluids applied in turbulent flow were the mixture ratio range from 40∶60 to 60∶40 and temperature higher than 40℃ at mass fraction of 0.5 %.

Key words: nanofluids, thermal conductivity, viscosity, cluster size, mixture ratio

中图分类号:

TK124

翟玉玲,王江,李龙,马明琰,姚沛滔. 粒径混合比对Al₂O₃/水纳米流体传热性能影响及评价[J]. 化工进展, 2019, 38(11): 4865-4872.

Yuling ZHAI,Jiang WANG,Long LI,Mingyan MA,Peitao YAO. Evaluation and effect of mixture ratio on heat transfer performance of Al₂O₃/water nanofluids[J]. Chemical Industry and Engineering Progress, 2019, 38(11): 4865-4872.

图/表 13

图1 实验测量值与去离子水标准值对比[10]

表1 判断纳米流体是否适用于层流和紊流传热的准则

$c μ c λ = μ n f - μ b f / μ b f λ n f - λ b f / λ b f$

Prasher等^[12]提出

若c_μ /c_λ <4，适用于层流

若c_μ /c_λ >4，不适用于层流

$M o = λ n f λ b f$

Simons等^[13]提出

若Mo>1, 适用于层流；且Mo数越大，综合传热性能越好

紊流

$M o = λ n f λ b f 0.67 × ρ n f ρ b f 0.8 × c p, n f c p, b f 0.33 × μ n f ν b f - 0.47$

Timofeeva等^[14]提出

若Mo>1，适用于紊流；且Mo数越大，综合传热性能越好

表1 判断纳米流体是否适用于层流和紊流传热的准则

区域

准则

主要结论

层流

$c μ c λ = μ n f - μ b f / μ b f λ n f - λ b f / λ b f$

Prasher等^[12]提出

若c_μ /c_λ <4，适用于层流

若c_μ /c_λ >4，不适用于层流

$M o = λ n f λ b f$

Simons等^[13]提出

若Mo>1, 适用于层流；且Mo数越大，综合传热性能越好

紊流

$M o = λ n f λ b f 0.67 × ρ n f ρ b f 0.8 × c p, n f c p, b f 0.33 × μ n f ν b f - 0.47$

Timofeeva等^[14]提出

若Mo>1，适用于紊流；且Mo数越大，综合传热性能越好

图2 沉降图

图3 50nm Al2O3纳米流体和粒子混合比为50∶50的Al2O3/水纳米流体的TEM图

图4 Al2O3/水组合纳米流体热导率随混合比和温度的变化

图5 Al2O3/水纳米流体有效热导率随温度和混合比的变化及与文献数据对比

图6 Al2O3/水组合纳米流体黏度随混合比和温度的变化

图7 相对黏度随温度和混合比的变化及与文献数据的对比（Soltani等，MgO-MWCNT/乙二醇,1.0%；Hamid等，TiO2-SiO2/水-乙二醇,1.0%）

图8 体积分数为1.0%的Al2O3 /水组合纳米流体的粒径分布

图9 样品A~D的团聚体平均尺寸和沉淀速度

图10 层流对流传热过程Al2O3/水纳米流体cμ /cλ (Mo)值随温度和混合比的变化

图11 紊流对流传热过程Al2O3/水纳米流体Mo数随温度和混合比的变化

表2 层流对流传热过程中的判断准则及优化混合比

范围	c_μ /c_λ <4	Mo>1	结果
A	√	×	不适合应用于传热
B	√	√	适合应用于传热
C	×	√	不适合应用于传热
优化混合比			① φ=0.5%, 40∶60, T=25～55℃; 70∶30、80∶20, T= 45～55℃ ② φ=1%, 50∶50, T=25～55℃; 80∶20、10∶90，T= 35～55℃

参考文献 22

1	BASHIRNEZHAD K , BAZRI S , SAFAEI M R , et al . Viscosity of nanofluids: a review of recent experimental studies [J]. International Communications in Heat and Mass Transfer, 2016, 73: 114-123.
2	AKILU S , SHARMA K V , BAHETA A T ,et al . A review of thermophysical properties of water based composite nanofluids [J]. Renewable and Sustainable Energy Reviews, 2016, 66: 654-678.
3	LEONG K Y , AHMAD K Z , ONG H C, et al . Synthesis and thermal conductivity characteristic of hybrid nanofluids—A review [J]. Renewable and Sustainable Energy Reviews, 2017, 75: 868-878.
4	NABIL M F , AZMI W H , HAMID K A , et al . Thermo-physical properties of hybrid nanofluids and hybrid nanolubricants: a comprehensive review on performance [J]. International Communications in Heat and Mass Transfer, 2017, 83: 30-39.
5	HO C J, HUANG J B , TSAI P S , et al . Preparation and properties of hybrid water-based suspension of Al₂O₃ nanoparticles and MEPCM particles as functional forced convection fluids [J]. International Communications in Heat and Mass Transfer, 2010, 37: 490-494.
6	SURESH S , VENKITARAJ K P , SELVAKUMAR P , et al . Synthesis of Al₂O₃-Cu/water hybrid nanofluids using two step method and its thermo physical properties [J]. Colloids Surface, 2011, 388: 41-48.
7	BOTHA S S , NDUMGU P , BLADERGROEN B J . Physicochemical properties of oil-based nanofluids containing hybrid structures of silver nanoparticles supported on silica [J]. Industrial and Engineering Chemistry Research, 2011, 50: 3017-3077.
8	ASADI A . A guideline towards easing the decision-making process in selecting an effective nanofluid as a heat transfer fluid [J]. Energy Conversion and Management, 2018, 175: 1-10.
9	BABU J A R , KUMAR K K , RAO S S . State-of-art review on hybrid nanofluids [J]. Renewable and Sustainable Energy Reviews, 2017, 77: 551-565.
10	杨世铭，陶文铨 . 传热学[M]. 4版. 北京：高等教育出版社，2006.
	YANG Shiming , TAO Wenquan . Heat transfer [M]. 4th ed. Beijing: Higher Education Press, 2006.
11	HIEMENZ P C . Principles of colloid and surface chemistry [M]. Marcel Dekker, Inc., 1977.
12	PRASHER R , DAVID S , WANG J , et al . Measurements of nanofluid viscosity and its implications for thermal applications[J]. Applied Physics Letters, 2006, 89: 133108.
13	SIMONS R E . Comparing heat transfer rates of liquid coolants using the Mouromtseff Number [J]. Electronic Cooling, 2006, 12: 35-39.
14	TIMOFEEVA E V , ROUTBORT J L , SINGH D . Particle shape effects on thermophysical properties of alumina nanofluids [J]. Journal Applied Physics, 2009, 106: 014304.
15	HAMID K A , AZMI W H , NABIL M F , et al . Experimental investigation of thermal conductivity and dynamic viscosity on nanoparticle mixture ratios of TiO₂-SiO₂ nanofluids [J]. International Journal of Heat and Mass Transfer, 2018, 116: 1143-1152.
16	SHARIPUR M , TSHIMANGA N , MEYER J P , et al . Experimental investigation and model development for thermal conductivity of α-Al₂O₃-glycerol nanofluids [J]. International Communications in Heat and Mass Transfer, 2017, 85: 12-22.
17	ANGAYARKANNI S A , PHILIP J . Review on thermal properties of nanofluids: recent developments [J]. Advances in Colloid and Interface Science, 2015, 225: 146-176.
18	CHIAM H W , AZMI W H , USRI N A , et al . Thermal conductivity and viscosity of Al₂O₃ nanofluids for different based ratio of water and ethylene glycol mixture [J]. Experimental Thermal and Fluid Science, 2017, 81: 420-429.
19	PARSIAN A , AKBARI M . New experimental correlation for the thermal conductivity of ethylene glycol containing Al₂O₃-Cu hybrid nanoparticles [J]. Journal of Thermal Analaysis and Calorimetry, 2018, 131: 1605-1613.
20	KUMAR D D , ARASU A V . A comprehensive review of preparation, characterization, properties and stability of hybrid nanofluids [J]. Renewable and Sustainable Energy Review, 2018, 81: 1669-1689.
21	SOLTANI O , AKBARI M . Effects of temperature and particles concentration on the dynamic viscosity of MgO-MWCNT/ethylene glycol hybrid nanofluid: experimental study [J]. Physica E, 2016, 84: 564-570.
22	PRASHER R . Effect of aggregation kinetics on thermal conductivity of nanoscale colloidal solutions (nanoflui) [J]. Nano Letters, 2006, 6: 1529-1534.

[1]	张岱凌, 丁玉梅, 左夏华, 黎昊为, 杨卫民, 阎华, 安瑛. 废弃墨粉纳米流体的光热特性[J]. 化工进展, 2023, 42(9): 4791-4798.
[2]	娄宝辉, 吴贤豪, 张驰, 陈臻, 冯向东. 纳米流体用于二氧化碳吸收分离研究进展[J]. 化工进展, 2023, 42(7): 3802-3815.
[3]	陈蔚阳, 宋欣, 殷亚然, 张先明, 朱春英, 付涛涛, 马友光. 矩形微通道内液相黏度对气泡界面的作用机制[J]. 化工进展, 2023, 42(7): 3468-3477.
[4]	谢志伟, 吴张永, 朱启晨, 蒋佳骏, 梁天祥, 刘振阳. 植物油基Ni_0.5Zn_0.5Fe₂O₄磁流体的黏度特性及磁黏特性[J]. 化工进展, 2023, 42(7): 3623-3633.
[5]	孙征楠, 李洪晶, 荆国林, 张福宁, 颜飚, 刘晓燕. EVA及其改性聚合物在原油降凝剂领域的应用[J]. 化工进展, 2023, 42(6): 2987-2998.
[6]	郭文杰, 翟玉玲, 陈文哲, 申鑫, 邢明. Al₂O₃-CuO/水混合纳米流体对流传热性能及热经济性分析[J]. 化工进展, 2023, 42(5): 2315-2324.
[7]	李光文, 华渠成, 黄作鑫, 达志坚. 聚甲基丙烯酸酯类黏度指数改进剂的研究进展[J]. 化工进展, 2023, 42(3): 1562-1571.
[8]	朱启晨, 吴张永, 王志强, 蒋佳骏, 李翔. 低温下硅油基纳米磁流体沉降稳定性与黏度特性[J]. 化工进展, 2023, 42(10): 5101-5110.
[9]	李鲁, 鲍穗, 张李明, 汪然, 陶正红, 杨兴祥. 卡拉胶-魔芋胶复合凝胶基香精微胶囊的制备与表征[J]. 化工进展, 2022, 41(S1): 376-381.
[10]	陆诗建, 刘玲, 刘滋武, 郭伯文, 俞徐林, 梁艳, 赵东亚, 朱全民. AEP-DPA-CuO相变纳米流体吸收CO₂稳定性[J]. 化工进展, 2022, 41(8): 4555-4561.
[11]	李钰璨, 胡定华, 刘锦辉. 氧化铝纳米流体液滴瞬态蒸发速率的演化特性分析[J]. 化工进展, 2022, 41(7): 3493-3501.
[12]	李佩珊, 张梦辰, 李铭杰, 郑文镳, 刘敏超, 谢高艺, 徐晓龙, 刘长宇, 郏建波. 基于二维材料膜构筑纳米流体通道的研究进展[J]. 化工进展, 2022, 41(7): 3745-3757.
[13]	林清宇, 王祝, 冯振飞, 凌彪, 陈镇. 扭带结构影响管内传热与熵产的研究进展[J]. 化工进展, 2022, 41(11): 5709-5721.
[14]	禹言芳, 陈雅鑫, 孟辉波, 王宗勇, 吴剑华. Lightnin静态混合器内纳米流体湍流传热特性分析[J]. 化工进展, 2021, 40(S2): 30-39.
[15]	王英梅, 牛爱丽, 张兆慧, 展静, 张学民. 二氧化碳水合物快速生成方法研究进展[J]. 化工进展, 2021, 40(S2): 117-125.

粒径混合比对Al₂O₃/水纳米流体传热性能影响及评价

Evaluation and effect of mixture ratio on heat transfer performance of Al₂O₃/water nanofluids

RichHTML

PDF (PC)

可视化

摘要/Abstract

引用本文

使用本文

图/表 13

参考文献 22

相关文章 15

编辑推荐

Metrics

本文评价