人類使用的能源選項中，太陽熱能發電及核能皆為低碳排放的重要能源選項之一。高溫熔融鹽的應用中，集光型太陽熱能發電系統經常使用熔融鹽作為工作載體;第四代核能電廠亦有採用熔融鹽為工作載體。液態熔融鹽具有高熱容量及高熱穩定性等優點，但其熱傳能力及熱均溫性都不佳, 且其熱容量仍不及水，有進一步提升的必要。
本研究主要目的在探討熔融鹽在摻雜奈米顆粒對比熱及熱傳能力的影響。為了製備出高品質的熔鹽樣本，本研究發展一系列創意的實驗平台及製備流程。之後，針對一種氟化鹽(FLINAK)及一種硝酸鹽(HITEC)先進行一系列的熱物理性質量測，包括有熔點、熱裂解溫度、熱擴散、熱傳導及比熱等，並將結果與相關文獻進行比對，確保熔融鹽樣本製備流程的正確性及其品質。
本研究首先探討不同摻雜濃度的奈米顆粒(氧化鋁, 約40 nm)對於HITEC比熱的影響。這種添加奈米顆粒的HITEC，以奈米HITEC稱之。由於本研究之奈米HITEC並無添加任何界面活性劑，為了避免奈米顆粒沈澱而造成採樣上的誤差，本研究設計一創意的製備流程並建立相關設備。比熱是委託工研院採用熱示差掃瞄卡量計(Differential Scanning Calorimeter, DSC)進行量測。DSC主要藉由記錄樣本在固定加熱速率下的吸熱及放熱過程，進而推算樣本之比熱。實驗結果顯示，奈米HITEC存在一個最佳濃度0.063 wt.%，可增強HITEC比熱，最大達19.9%，過高或過低的摻雜濃度都無法得到最優的強化。本研究也發現當濃度超過2 wt.%時， 將對HITEC比熱產生負面的效應，比未摻雜奈米顆粒的熔鹽具有更低的比熱。此外，在電子顯微鏡下觀察的奈米HITEC發現，濃度為0.016 wt.%時，奈米顆粒呈現均勻的分佈且幾乎觀察不到奈米顆粒聚集現象的發生。但隨著摻雜濃度的提高，奈米顆粒聚集及相互鏈結的情況逐漸顯著。為進一步探究奈米HITEC之比熱存在最佳濃度的成因，本研究利用電子顯微影像，進行獨立奈米顆粒及聚集粒子團的尺寸及數目的統計分析，進而發展一簡易模型，描述顆粒與流體間的介面面積。模型分析結果發現，添加濃度超過0.023 wt.%時，奈米顆粒將開始發生聚集現象，形成粒子團，獨立奈米顆粒的總表面積隨之下降，並開始有粒子團的表面積加入，但總固液介面面積仍呈現下降的趨勢。在濃度為0.048 wt.%時，固液介面總面積達最低值，此後，總介面面積隨著粒子濃度的增加而增加。本研究發現在摻雜濃度0.063 wt.%時，獨立奈米顆粒及粒子團(直徑分佈約0.2­0.6 μm)，兩者粒子團貢獻的表面積相當，此介面組合對於奈米HITEC比熱的提升最有幫助，文獻已指出粒子與熔鹽的介面現象是提升比熱的主因。
本研究為了進一步探討不同奈米顆粒濃度對於HITEC熔鹽層流於迷你流道熱傳能力的影響，發展了一套創意的活塞式奈米熔融鹽實驗量測平台。此平台提供顆粒濃度小於或等於0.25 wt.%的條件下，奈米HITEC可在30分鐘內維持良好的懸浮性。之後，本研究設計一直徑2.1 mm、長120 mm的測試流道，分別量測其軸向三個位置的表面溫度及流道進出口溫度，進而利用牛頓冷卻定律決定熱傳遞係數。研究結果發現，未添加奈米顆粒的HITEC，其管路平均的紐賽爾數(Nusselt number, Nu)與文獻中廣為引用的經驗公式比較的誤差在10%以內，而添加濃度0.25 wt.%的奈米顆粒可提升平均Nu最高約11.6%。具有比熱最高增強效果的0.063wt%，其平均Nu也可提高約9.2%，且1小時內無觀察到奈米顆粒發生聚集沈澱的現象。此外，本研究發展一經驗公式，描述奈米熔融鹽在層流的情況下，摻雜不同濃度的奈米顆粒與熱傳遞係數的關係。相較於本研究之實驗數據，該經驗式可確保94%的數據在誤差10%之內。
本研究的結果顯示，適度的將硝酸鹽HITEC摻雜直徑約40nm的氧化鋁奈米顆粒，濃度約0.063 wt.%，除可以提升HITEC 的儲熱能力達19.9%之外，同時也可增加熱傳的能力，十分適合應用於集熱式太陽熱能及相關熱儲系統的工作流體。

Both solar thermal and nuclear power systems are important energy options with low carbon emissions. Molten salt has been proposed as the working fluid in a concentrating solar power system, and it is also suggested to be employed in a molten salt reactor, which is one of six types of Generation-IV power systems. Molten salts present feature of high heat capacity and high thermal stability. Nevertheless, molten salts usually exhibit relatively poor heat transfer performance and non-uniform temperature distribution. Besides, the specific heat capacity of molten salts is not as high as water and there is a need for the enhancement.
This study demonstrates the variation of specific heat capacity and heat transfer performance in the molten salt doped with nanoparticles. Innovative apparatus and procedures have been developed to prepare the specimen of molten salt with high quality. Moreover, a series of thermal-physical characteristics, including melting point, decomposition temperature, thermal diffusivity, thermal conductivity and specific heat capacity for a pure fluoride salt (FLINAK) and a nitrate salt (HITEC) are measured and compared with that reported in the literature to validate the specimen prepared.
At first, this work studied the effect of alumina nanoparticles (mean diameter about 40 nm) concentration on the specific heat capacity of molten HITEC salt, which is called nano-HITEC. The nano-HITEC salt in this study is free of surfactant and an innovative preparation process and sampling apparatus for molten nano-HITEC have been established in the present study to avoid the possible precipitation of nanoparticles. The specific heat of molten HITEC and nano-HITEC are measured using a power compensated differential scanning calorimeter (DSC) at the Industrial Technology Research Institute (ITRI) of Taiwan. A power compensated DSC monitors the endothermic or exothermic reaction of specimen under a constant heating rate to determine the specific heat capacity of specimen. In this work, an optimal concentration of 0.063 wt.% is identified, demonstrating the highest enhancement on the specific heat capacity of 19.9%. Lower or higher concentration of nanoparticles tends to reduce the enhancement. For the concentration of 2 wt.%, the negative effect of doping the nanoparticles on the specific heat capacity appears for all temperatures in the present study. The SEM images after solidification of samples reveal that near uniform dispersion of nanoparticles with negligible agglomeration for the concentration smaller than 0.016 wt.%. The agglomeration becomes significant and the particle clusters seem to be inter-connected for higher concentrations. Moreover, this study conducts a statistical analysis on the number of isolated particles and number and size of clusters using SEM images to develop a simplified model, which describes the area of particle-liquid interface of nano-HITEC fluid with different concentration. The results indicate that the agglomeration of nanoparticles occurs as the concentration is over 0.023 wt.%; clusters with different sizes are formed and the total area of isolated particles is decreased and the clusters begin to contribute to the total interfacial areas with the overall area decreasing at the beginning. The minimum particle-liquid interface take place at concentration of 0.048 wt.%. Subsequently, the total interfacial area increases with increasing concentration. It is found that the optimal concentration is corresponding to approximately the concentration that the contribution of isolated nanoparticles and particle clusters, size ranging from 0.2 to 0.6 μm, to the interfacial area are approximately the same. The interfacial phenomena at the particle (isolated or cluster) fluid interface is proposed in the literature to be the primary reason for the enhancement of specific heat capacity in nano-salts.
Subsequently, the effect of nanoparticle concentration on the laminar convective heat transfer performance for molten nano-HITEC fluid in a mini-circular tube is investigated. An innovative piston driven molten salt apparatus and preparation process of molten HITEC nanofluild are developed to prevent the precipitation of nanoparticles during the measuring process. The piston molten salt pump provides steady flow through the test section which the channel diameter and length are 2.1 mm and 120 mm, respectively. The mean heat transfer of molten salt flow can be evaluated by Newton’s cooling law based on the inlet/outlet temperature and three wall temperatures measured at three axial locations. The results demonstrate that the measurement of mean Nusselt number of the pure HITEC fluid in this study be in good agreement within ±10% with a well-known correlation. A concentration of nanoparticles of 0.25 wt.% in the nano-HITEC, which can be maintained uniform dispersion for about 30 minutes, results in the maximum enhancement of mean Nusselt number of 11.6%. On the other hand, a concentration of 0.063 wt.% provides 9.2% enhancement on the mean Nusselt number of HITEC nanofluid, and precipitation phenomenon is not observed within an hour. In addition, a new correlation with consideration of particle concentration for the laminar convective heat transfer performance of the nano-HITEC fluid in the present minichannel is developed, by which more than 93.9% of the experimental data can be predicted within ±10% of deviation.
A nano-HITEC fluid with concentration of 0.063 wt.% of alumina particle of about 40 nm demonstrates best enhancements of its specific heat capacity of 19.9% as well as near best heat transfer performance in this study. This suggests that nano-HITEC of 0.063 wt.% of nano alumina particles of about 40 nm may serve as a working fluid for applications in a thermal storage system or a concentrating solar power system.

[1] P. Viebahn, Y. Lechon, F. Trieb, The potential role of concentrated solar power (CSP) in Africa and Europe-A dynamic assessment of technology development, cost development and life cycle inventories until 2050, Energy Policy 39 (2011) 4420–4430.
[2] D. Kearney, U. Herrmann, P. Nava, B. Kelly, R. Mahoney, J. Pacheco, R. Cable, N. Potrovitza, D. Blake, H. Price, Assessment of a molten salt heat transfer fluid in a parabolic trough solar field, Journal of Solar Energy Engineering 125 (2003) 170–176.
[3] M. Liu, N.H. Steven Tay, S. Bell, M. Belusko, R. Jacob, G. Will, W. Saman, F. Bruno, Review on concentrating solar power plants and new developments in high temperature thermal energy storage technologies, Renewable & Sustainable Energy Reviews 53 (2016) 1411–1432.
[4] D. Mills, Advances in solar thermal electricity technology, Solar Energy 76 (2004) 19–31.
[5] O. Behar, A. Khellaf, K. Mohammedi, A review of studies on central receiver solar thermal power plants, Renewable & Sustainable Energy Reviews 23 (2013) 12–39.
[6] K. Vignarooban, X. Xu, A. Arvay, K. Hsu, A.M. Kannan, Heat transfer fluids for concentrating solar power systems–A review, Applied Energy 146 (2015) 383–396.
[7] M. Mehos, C. Turchi, J. Vidal, M. Wagner, Z. Ma, Concentrating Solar Power Gen3 Demonstration Roadmap, NREL technical report, NREL/TP–5500–67464 (2017) 9.
[8] J. Wang, S. Yang, C. Jiang1, Y. Zhang, P. D. Lund ,Status and future strategies for Concentrating Solar Power in China, Energy Science and Engineering 5 (2017) 100–109.
[9] T. Abram, S. Ion, Generation–IV nuclear power: A review of the state of science, Energy Policy 36 (2008) 4323–4330 .
[10] V. Ignatiev, O. Feynberg, I. Gnidoi, A. Merzlyakov, V. Smirnov, A. Surenkov, I. Tretiakov, R. Zakirov, V. Afonichkin, A. Bovet, V. Subbotine, A. Panove, A. Toropov and A. Zherebtsov, Progress in development of LI, Be, Na/F Molten Salt Actinide Recycler & Transmuter Concept, Proceedings of ICAPP, Nice, France, 7548 (2007).
[11] E. M.Lucotte, D. Heuer, M. Allibert, X. Doligez, V. Ghetta, C. L. Brun, Optimization and simplification of the concept of non-moderated thorium molten salt reactor, International Conference on the physics of reactors, Switzerland, (2008) 14–19.
[12] H. Kim, D. A. Boysen, J. M. Newhouse, B. L. Spatocco, B. Chung, P. J. Burke, D. J. Bradwell, K. Jiang, A. A. Tomaszowska, K. Wang, W. Wei, L. A. Ortiz, S. A. Barriga, S. M. Poizeau, D. R. Sadoway, Liquid Metal Batteries: Past, Present, and Future, Chemical Reviews 113 (2013) 2075–2099.
[13] S. Liu, W. Han, B. Cui, X. Liu, F. Zhao, J. Stuart, S. Licht, A novel rechargeable zinc-air battery with molten salt electrolyte, Journal of Power Sources 342 (2017) 435–441.
[14] L.C. Olson, Material corrosion in molten LiF–NaF–KF eutectic salt, Doctoral dissertation, University of Wisconsin-Madison, (2009).
[15] ]M. Kondo, T. Nagasaka, Q, Xu, T. Muroga, A. Sagara, N. Noda, D. Ninomiya, M. Nagaura and A. Suzuki, Corrosion characteristic of reduced activation ferritic steel, JLF–1 (8.92Cr–2W) in molten salts Flibe and FLINAK, Fusion Engineering and Design 84 (2009) 1081–1085.
[16] O. Benes, R.J.M. Konings, Thermodynamic properties and phase diagrams of fluoride salt for nuclear applications, Journal of Fluorine Chemistry 130 (2009) 22–29.
[17] V. Khokhlov, V. Ignatiev, V. Afonichkin, Evaluating physical properties of molten salt reactor fluoride mixtures, Journal of Fluorine Chemistry 130 (2009) 30–37.
[18] J.C. Maxwell, A treatise on electricity and magnetism 3th edition., Oxford, Clarendon, (1892), 435–441.
[19] R.L. Hamilton, O.K. Crosser, Thermal conductivity of heterogeneous two-component systems, Industrial & Engineering Chemistry Research 1 (1962), 187–191.
[20] S.U.S. Choi, J.A. Eastman, Enhancing thermal conductivity of fluids with nanoparticles, ASME International Mechanical Engineering Congress and Exposition 66 (1995) 99–105.
[21] W. Duangthongsuk, S. Wongwises, Measurement of temperature–dependent thermal conductivity and viscosity of TiO2-water nanofluids, Experimental Thermal and Fluid Science 33 (2009) 706–714.
[22] J.H. Lee, K.S. Hwang, S.P. Jang, B.H. Lee, J.H. Kim, S.U.S. Choi, C.J. Choi, Effective viscosities and thermal conductivities of aqueous nanofluids containing low volume concentrations of Al2O3 nanoparticles, International Journal of Heat and Mass Transfer 51 (2008) 2651–2656.
[23] M. Hemmat Esfe, A. Karimipour, W.M. Yan, M. Akbari, M.R. Safaei, M. Dahari, Experimental study on thermal conductivity of ethylene glycol based nanofluids containing Al2O3 nanoparticles, International Journal of Heat and Mass Transfer 88 (2015) 728–734.
[24] X. Li, C. Zou, X. Lei, W. Li, Stability and enhanced thermal conductivity of ethylene glycol-based SiC nanofluids, International Journal of Heat and Mass Transfer 89 (2015) 613–619.
[25] J.Y. Jung, J. Koo, Y.T. Kang, Model for predicting the critical size of aggregates in nanofluids, Journal of Mechanical Science and Technology 27 (2013) 1165–1169.
[26] K.N. Shukla, T.M. Koller, M.H. Rausch, A.P. Froba, Effective thermal conductivity of nanofluids – A new model taking into consideration Brownian motion, International Journal of Heat and Mass Transfer 99 (2016) 532–540.
[27] D. Song, J. Zhou, Y. Wang, D. Jing, Choice of appropriate aggregation radius for the descriptions of different properties of the nanofluids, Applied Thermal Engineering 103 (2016) 92–101.
[28] A. Vatani, P.L. Woodfield, D.V. Dao, A survey of practical equations for prediction of effective thermal conductivity of spherical-particle nanofluids, Journal of Molecular Liquids 211 (2015) 712–733.
[29] D.K. Devendiran, V.A. Amirtham, A review on preparation methods and challenges of nanofluids, Renewable & Sustainable Energy Reviews 54 (2014) 115–125.
[30] T. Sokhansefat, A. B. Kasaeian, F. Kowsary, Heat transfer enhancement in parabolic trough collector tube using Al2O3/synthetic oil nanofluid, Renewable & Sustainable Energy Reviews 33 (2014) 636–644.
[31] A. Mwesigye, Z. Huan, J.P. Meyer, Thermodynamic optimisation of the performance of a parabolic trough receiver using synthetic oil–Al2O3 nanofluid, Applied Energy 156 (2015) 398–412.
[32] A. Mwesigye, Z. Huan, J.P. Meyer, Thermal performance and entropy generation analysis of a high concentration ratio parabolic trough solar collector with Cu–Therminol®VP–1 nanofluid, Energy Conversion and Management 120 (2016) 449–465.
[33] E. Bellos, C. Tzivanidis, K.A. Antonopoulos, G. Gkinis, Thermal enhancement of solar parabolic trough collectors by using nanofluids and converging-diverging absorber tube, Renewable Energy, 94 (2016) 213–222.
[34] A. Kasaeian, S. Daviran, R.D. Azarian, A. Rashidi, Performance evaluation and nanofluid using capability study of a solar parabolic trough collector, Energy Conversion and Management 89 (2015) 368–375.
[35] H. Riazi, T. Murphy, G.B. Webber, R. Atkin, S.S. Mostafavi, R.A. Taylor, Specific heat control of nanofluids : A critical review, International Journal of Thermal Sciences 107 (2016) 25–38.
[36] S. K. Verma, A. K. Tiwari, Progress of nanofluid application in machining: A review, Energy Conversion and Management 100 (2015) 324–346.
[37] S.Q. Zhou, R. Ni, Measurement of the specific heat capacity of water-based Al2O3 nanofluid, Applied Physics Letters 92 (093123) (2012) 1–3.
[38] H. O’Hanley, J. Buongiorno, T. McKrell and L.W. Hu, Measurement and model validation of nanofluid specific heat capacity with differential scanning calorimetry, Advances in Mechanical Engineering 181079 (2012) 1–6.
[39] D. Shin and D. Banerjee, Effects of silica nanoparticles on enhancing the specific heat capacity of carbonate salt eutectic, International Journal of Structure Changes in Solid - Mechanics and Application 2 (2010) 25–31.
[40] D. Shin, D. Banerjee, Enhanced specific heat of silica nanofluid, Journal of Heat Transfer 133 (024501) (2011) 1–3.
[41] D. Shin, D. Banerjee, Enhancement of specific heat capacity of high-temperature silica nanofluids synthesized in alkali chloride salt eutectics for solar thermal-energy storage applications, International Journal of Heat and Mass Transfer 54 (2011) 1064–1070.
[42] D. Shin, D. Banerjee, Enhancement of heat capacity of molten salt eutectics using inorganic nanoparticles for solar thermal energy applications, Developments in Strategic Materials and Computational Design II: Ceramic Engineering and Science Proceedings 32 (2011) 119–126.
[43] D. Shin, D. Banerjee, Enhanced specific heat capacity of nanomaterials synthesized by dispersing silica nanoparticles in eutectic mixtures, Journal of Heat Transfer 135 (032801) (2013) 1–8.
[44] H. Tiznobaik, D. Shin, Enhanced specific heat capacity of high temperature molten salt-based nanofluids, International Journal of Heat and Mass Transfer 57 (2013) 542–548.
[45] B. Dudda, D. Shin, Effect of nanoparticle dispersion on specific heat capacity of a binary nitrate eutectic for concentrated solar power applications, International Journal of Thermal Sciences 69 (2013) 37–42.
[46] E.Hamdy, S. Ebrahim, F. Abulfotuh, M. Soliman, Effect of multi-walled carbon nanotubes on thermal properties of nitrate molten salts, Proceedings of IRSEC, Marrakech, Morocco,17045334 (2016).
[47] Z. Zhang, Y. Yuan, L. Ouyang, Q. Sun, X. Cao, S. Alelyani, Enhanced thermal properties of Li2CO3–Na2CO3–K2CO3 nanofluids with nanoalumina for heat transfer in high temperature CSP systems, Journal of Thermal Analysis and Calorimetry, 128 (2017) 1783–1792.
[48] Z. Zhang , Y. Yuan, N.an Zhang, Q. Sun a, X. Cao, L. Sun, Thermal properties enforcement of carbonate ternary via lithium fluoride: A heat transfer fluid for concentrating solar power systems, Renewable Energy 111 (2017) 523–531.
[49] L. Sang, T. Liu, The enhanced specific heat capacity of ternary carbonates nanofluids with different nanoparticles, Solar Energy Materials and Solar Cells 169 (2017) 297–303.
[50] B. Ma, D. Banerjee, Experimental measurements of thermal conductivity of alumina nanofluid synthesized in salt melt, AIP Advances 7 (2017) 115124.
[51] M. Chieruzzia, G. F. Cerritellia, A. Miliozzib, J. M. Kennya, L. Torrea ,Heat capacity of nanofluids for solar energy storage produced by dispersing oxide nanoparticles in nitrate salt mixture directly at high temperature, Solar Energy Materials and Solar Cells 167 (2017) 60–69.
[52] S. Jung, B. Jo, D. Shin, D. Banerjee, Experimental validation of simple analytical model for specific heat capacity of aqueous nanofluids, SAE technical paper 1731 (2010) 1–7.
[53] S. Jung, D. Banerjee, A simple analytical model for specific heat of nanofluid with tube shaped and disc shaped nanoparticles, Proceedings of the ASME/JSME 8th Thermal Engineering Joint Conference 44372 (2011) 1–6.
[54] B.X. Wang, L.P. Zhou and X.F. Peng, Surface and size effects on the specific heat capacity of nanoparticles, International Journal of Thermophysics 27 (2006) 139–151.
[55] L. Wang, Z. Tang, S. Meng, D. Liang and G. Li, Enhancement of molar heat capacity of nanostructured Al2O3, Journal of Nanoparticle Research 3 (2001) 483–487.
[56] C.L. Snow, C.R. Lee, Q.Shin, J. B. Goates, B.F. Woodfield, Size dependence of the heat capacity and thermodynamic properties of hematitie (α–Fe2O3), Journal of Chemical and Thermodynamics 42 (2010) 1142–1151.
[57] C.A. Nieto de Castro, S.M.S. Murshed, M.J.V. Lourenco, F.J.V. Santos, M.L.M. Lopes, Franca, Enhanced thermal conductivity and specific heat capacity of carbon nanotubes ionanofluids, International Journal of Thermal Science 62 (2012) 34–39.
[58] I. C. Nelson, D. Banerjee, Flow loop experiments using polyalphaolefin nanofluids. Journal of Thermophysics and Heat Transfer 23 (2009) 752–761.
[59] N.J. Bridges, A.E. Visser, E.B. Fox, Potential of nanoparticle enhanced ionic liquid (NEILs) as advanced heat transfer fluids, Energy and Fuels 25 (2011) 4862–4864
[60] M.C. Lu, C.H. Huang, Specific heat capacity of molten salt–based alumina nanofluid, Nanoscale Research Letters 8:292 (2013) 1–7.
[61] M. Chieruzzi, G.F. Cerritelli, A. Miliozzi, J.M. Kenny, Effect of nanoparticles on heat capacity of nanofluids based on molten salts as PCM for thermal energy storage, Nanoscale Research Letters 8:448 (2013) 1–9
[62] J. Buongiorno, Convective transport in nanofluids, Journal of Heat Transfer 128 (2006) 240–250.
[63] P. Xiao, L. Guo, X. Zhang, Investigations on heat transfer characteristic of molten salt flow in helical annular duct, Applied Thermal Engineering 88 (2015) 22–32.
[64] Y.T. Wu, L. Bin, C.F. Ma, H. Guo, Convective heat transfer in the laminar-turbulent transition region with molten salt in a circular tube, Experimental Thermal and Fluid Science 33 (2009) 1128–1132.
[65] B. Liu, Y. T. Wu, C.F. Ma, M. Ye, H. Guo, Turbulent convective heat transfer with molten salt in a circular pipe, International Communications Journal of Heat and Mass Transfer 36 (2009) 912–916.
[66] Y.T. Wu, C. Chen, B. Liu, C.F. Ma, Investigation on forced convective heat transfer of molten salts in circular tubes, International Communications Journal of Heat and Mass Transfer 39 (2012) 1550–1555.
[67] J. Lu, S. He, J. Liang, J. Ding, J. Yang, Convective heat transfer in the laminar-turbulent transition region of molten salt in annular passage, Experimental Thermal and Fluid Science 51 (2013) 71–76
[68] J. Lu, S. He, J. Ding, J. Yang, J. Liang, Convective heat transfer of high temperature molten salt in a vertical annular duct with cooled wall, Applied Thermal Engineering 73 (2014) 1519–1524.
[69] X. Shen, J. Lu, J. Ding, J. Yang, Convective heat transfer of molten salt in circular tube with nonuniform heat flux, Experimental Thermal and Fluid Science 55 (2014) 6–11.
[70] Y.S. Chen, Y.Wang, J.H. Zhang, X.F. Yuan, J. Tian, Z.F. Tang, H.H. Zhu, Y. Fu, N.X.Wang, Convective heat transfer characteristics in the turbulent region of molten salt in concentric tube, Applied Thermal Engineering, 98 (2016) 213–219.
[71] Y.S. Chen, J. Tian, S.D. Sun, Q. Sun, Y. Fu, Z.F. Tang, H.H. Zhu, N.X. Wang, Characteristics of the laminar convective heat transfer of molten salt in concentric tube, Applied Thermal Engineering 125 (2017) 995–1001.
[72] Y.S. Chen, H.H. Zhu, J. Tian, Y. Fu, Z.F. Tang, N.X. Wang, Convective heat transfer characteristics in the laminar and transition region of molten salt in concentric tube, Applied Thermal Engineering 117 (2017) 682–688.
[73] J. Qian, Q.L. Kong, H.W. Zhang, Z.H. Zhu, W.G. Huang, W.H. Li, Experimental study for shell-and-tube molten salt heat exchangers, Applied Thermal Engineering 124 (2017) 616–623.
[74] B.C. Du, Y.L. He, K. Wang, H.H. Zhu ,Convective heat transfer of molten salt in the shell-and-tube heat exchanger with segmental baffles, International Journal of Heat and Mass Transfer 113 (2017) 456–465.
[75] T. Kunugi, S. Satake, A. Sagara, Direct numerical simulation of turbulent free-surface high Prandtl number fluid flows in fusion reactors, Nuclear Instruments and Methods in Physics Research Section: A 464 (2001) 165–171.
[76] Y.T. Wu, S.W. Liu, Y.X. Xiong, C.F. Ma, Y.L. Ding, Experimental study on the heat transfer characteristics of a low melting point salt in a parabolic trough solar collector system, Applied Thermal Engineering 89 (2015) 748–754.
[77] S. He, J. Lu, J. Ding, T. Yu, Y. Yuan, Convective heat transfer of molten salt outside the tube bundle of heat exchanger, Experimental Thermal and Fluid Science 59 (2014) 9–14.
[78] J. Lu, X. Shen, J. Ding, Q. Peng, Y. Wen, Convective heat transfer of high temperature molten salt in transversely grooved tube, Applied Thermal Engineering 61 (2013) 157–162.
[79] C. Chen, Y.T. Wu, S.T. Wang, C.F. Ma, Experimental investigation on enhanced heat transfer in transversally corrugated tube with molten salt, Experimental Thermal and Fluid Science 47 (2013) 108–116.
[80] M. Yang, X. Yang, X. Yang, J. Ding, Heat transfer enhancement and performance of the molten salt receiver of a solar power tower, Applied Energy 87 (2010) 2808–2811.
[81] A. Sagara, H. Yamanishi, S. Imagawa, T. Muroga, T. Uda, T. Noda, S. Takahashi, K. Fukumoto, T. Yamamoto, H. Matsui, A. Kohyama, H. Hasizume, S. Toda, A. Shimizu, A. Suzuki, Y. Hosoya, S. Tanaka, T. Terai, D.K. Sze, O. Motojima , Design and development of the Flibe blanket for helical-type fusion reactor FFHR, Fusion Engineering and Design 49–50 (2000) 661–666.
[82] S. Toda, S. Chiba, K. Yuki, M. Omae, A. Sagara, Experimental research on molten salt thermofluid technology using a high-temperature molten salt loop applied for a fusion reactor Flibe blanket, Fusion Engineering and Design 63–64 (2002) 405–409.
[83] S.Y. Chiba, K. Yuki, H. Hashizume, S. Toda, A. Sagara, Numerical research on heat transfer enhancement for high Prandtl number fluid, Fusion Engineering and Design A 81 (2006) 513–517.
[84] H.A. Mohammeda, G. Bhaskarana, N.H. Shuaiba, R. Saidurb, Heat transfer and fluid flow characteristics in microchannels heat exchanger using nanofluids: A review, Renewable & Sustainable Energy Reviews 15 (2011) 1502–1512
[85] J.P. Hartnett, M. Kostic, Heat transfer to Newtonian and non-Newtonian fluids in rectangular ducts. Advances in Heat Transfer 19 (2009) 247–356.
[86] R. W. Fox, Introduction to fluid mechanics, 4th edition, publisher Wiley, NY, (1994) 335–337.
[87] D.A. Skoog, F.J. Holler, T.A. Nieman, Principle of instrumental analysis, 5th edition, publisher Thomson Learning, U.S. (1998) 805–807.
[88] ASTM standard E1269–05, Standard test method for determining specific heat capacity by differential scanning calorimetry, ASTM Internaltional, PA, (2007) 1–5.
[89] M. S. Sohal, M.A. Ebner, P. Sabharwall, P. Sharpe, Engineering database of liquid salt thermophysical and thermochemical properties, Idaho National Laboratory, Idaho, INL/EXT–10–1897, (2010) 13.
[90] A.F. Mills, Heat transfer, 2nd ed., Prentice Hall, NJ, USA (1999) 875‐877.
[91] H.C. Brinkman, The viscosity of concentrated suspensions and solution, Journal of Chemical and physical 20 (1952) 571–581.
[92] D. Kearney , B. Kelly, U. Herrmann, R. Cable, J. Pacheco , R. Mahoney , H. Price , D. Blake, P. Nava and N. Potrovitza, Engineering aspects of a molten salt heat transfer fluid in a trough solar field, Energy 29 (2004) 861–870.
[93] Coastal Chemical Co., HITEC for Heat Transfer Salt, L.L.C. Brenntage company, 1–10
[94] M.D. Silverman, J.R. Engel, Survey of technology for storage of thermal energy in heat transfer salt, Oak ridge National Laboratory, ORNL/TM–5682 (1977) 6
[95] R. Tufeu, J.P. Petitet, L. Denielou, B. Le Neindre, Experimental determination of the thermal conductivity of molten pure salt and salt mixtures, International Journal of Thermophysics 6 (1985) 315–330.
[96] G. J. Janz, G.N. Truong, Melting and premelting properties of KNO3–NaNO2–NaNO3 Eutectic system, Journal of Chemical and Engineering Data 28 (1983) 201–202.
[97] M.M. Farooq, W.H. Giedt, N.Araki, Thermal diffusivity of liquids determined by flash heating of a three layer cell, International Journal of Thermophysics, 2 (1981) 39–54.
[98] P.L. Geiringer, Handbook of heat transfer media, Reinhold, London, (1962) 160–162.
[99] O. Odawara, I, Okada, K. kawamura, Measurement of the thermal diffusivity of HTS (a mixture of molten NaNO3–KNO3–NaNO2; 7–44–49 mol%) by optical interferometry, Journal of Chemical and Engineering Data, 22 (1977) 222–225
[100] Doupont Chemicals, HITEC heat transfer salt, E.I. du Pont de Nemours & Company, Inc., Wilmington, Delaware.
[101] R.K. Shah, A.L. London, Laminar flow forced convection in ducts, Academic Press, New York, NY. (1978) 124–129.