臺灣博碩士論文加值系統

全球約有81%的電力是由石化燃料提供，石化燃料會造成嚴重的環境汙染並加重溫室效應，因此發展再生能源便是一個非常重要的議題。太陽能為最有潛力之再生能源，傳統太陽能發電易受到日照時數與天氣狀況的限制，聚熱式太陽能發電廠則因能將太陽能轉為熱能儲存而不受此限。但目前聚熱式太陽能發電廠佔地廣且除能容量有限，因此加入相變材料，便是一種提升工作系統熱儲存的方法。在相變材料的應用過程中，遲滯溫度通常伴隨著出現，遲滯溫度的定義一般來說是熔點與凝固點的溫度差。遲滯溫度會使系統運作的效率降低，造成額外的熱損失，並使系統無法利用相變材料的潛熱以提升熱儲存。本研究合成並量測兩種殼層材料的鋅金屬微米粒子，結果顯示，合成的微米粒子具有非常好的熱穩定性，且鋅金屬/氧化鋁球殼粒子對降低遲滯溫度有較好的表現，目前推論造成遲滯溫度的主要因素為異質成核效應與加熱速率效應。此外，本研究亦建立熱傳導率量測系統，結果顯示熱傳導率隨粒子濃度增加而增加，且在1.2 vol.% Hitec添加氧化鋁奈米粒子之奈米流體中得到最高的熱傳導率，其值為0.908 ± 0.005 W/m-K，與未添加奈米粒子的熔鹽Hitec相比，其熱傳導率提升了21%，熱傳導率提升的原因是經棒式超音波震盪處理後的奈米流體，具有良好粒子分散性。另外，本研究量測Hitec添加氧化鋁奈米粒子奈米流體之比熱，量測結果顯示比熱隨著奈米粒子濃度升高而降低，其原因為氧化鋁奈米粒子之比熱小於Hitec，加入較多的奈米粒子會使比熱下降比例變大。本研究的實驗結果未來可應用在提升太陽能電廠工作流體的熱儲存與熱傳遞。

Around 81% of electricity is provided by fossil fuel. Fossil fuel could cause severe environmental pollution and deteriorate the greenhouse effect. Therefore, developing renewable energy becomes an urgent issue. Most of the renewable energy comes from solar energy. Photovoltaics would be limited by the diurnal limit of solar energy. On the contrary, concentric solar power plants would not be restricted by the diurnal limit because it can store solar energy as heat. However, concentric solar power plants occupy a large size of land and can only store a limited amount of heat. Therefore, adding phase change materials would be a solution to enhance the heat storage. During the applications of the phase change materials, a phenomenon called hysteresis temperature is widely observed. Hysteresis temperature is defined as the temperature difference between the melting point and crystallization point of a phase change material. Hysteresis temperature would lower the efficiency of the system, cause extra heat loss, and diminish the advantage of the phase change material. In this work, core-shell particles with two different shell materials (Zn microparticles coated with TiO2 and Al2O3) have been synthesized and investigated. The synthesized particles showed good thermal stability. Moreover, Zn microparticles coated with Al2O3 perform could lower the hysteresis temperature. Besides, the mechanism causing the hysteresis was investigated and it was found that the hysteresis resulted from heating rate effect and heterogeneous nucleation. Moreover, a thermal conductivity measurement system has been built. After the ultrasonication procedure, 1.2 vol.% Hitec doped with Al2O3 nanoparticle showed the highest thermal conductivity in this work. The thermal conductivity was 0.908 ± 0.005 W/m-K and was 21% enhancement compared with that of pure Hitec. The reason for the enhancement of thermal conductivity is that the nanoparticles in the fluid disperse very well after ultrasonication procedure. In addition, the measurements of the specific heat capacity of Hitec nanofluid have also been done. Based on the results, the specific heat capacity of Hitec nanofluid decreased with the increasing concentration. Compared to Hitec, Al2O3 nanoparticles have lower specific heat capacity, the addition of the Al2O3 nanoparticles will lower the specific heat capacity. The result in this work would be able to apply on the concentric power plants to enhance the heat storage and the heat transfer.

中文摘要 III
ABSTRACT V
目錄 VII
表目錄 X
圖目錄 XI
符號表 XV
第1章 緒論 1
1.1 研究動機 1
1.2 工作流體介紹 2
1.3 文獻回顧 2
1.3.1 提升熱儲存能力 3
1.3.2 提升熱傳遞能力 4
1.3.3 加入奈米粒子對溶液比熱容之影響 5
1.4 遲滯溫度介紹 6
1.5 研究目的 7
第2章 熱性質量測系統 11
2.1 溫度遲滯效應量測系統 11
2.1.1 差式掃描熱分析儀 11
2.1.2 比熱容量測原理 13
2.2 熱傳導率量測系統 13
2.2.1 暫態熱線法設備 13
2.2.2 暫態熱線法原理 15
2.3 熱性質量測系統不準度誤差分析 20
2.4 摘要 22
第3章 樣品配置與實驗流程 30
3.1 微米粒子之材料選擇及配置 30
3.2 熱傳導率實驗樣品 33
3.2.1 實驗樣品選擇 33
3.2.2 棒式超音波震盪處理 33
3.3 DSC量測步驟 34
3.3.1 遲滯溫度量測步驟 34
3.3.2 融化潛熱計算步驟 34
3.4 熱傳導率量測步驟 35
3.4.1 平衡電路實驗 35
3.4.2 熱傳導率實驗 35
3.4.3 計算熱傳導率 36
3.4.4 除錯方法 36
3.5 摘要 37
第4章 實驗量測結果 45
4.1 遲滯溫度量測結果 45
4.1.1 球殼粒子熱穩定測試 45
4.1.2 遲滯溫度 46
4.1.3 不同氧化層之遲滯溫度量測結果 47
4.1.4 遲滯溫度結果討論 47
4.2 熔鹽熱性質率量測結果 54
4.2.1 熱傳導率校正量測 54
4.2.2 Hitec添加氧化鋁奈米粒子之奈米流體熱傳導率量測結果 55
4.2.3 Hitec添加氧化鋁奈米粒子之奈米流體比熱量測結果 57
4.3 摘要 59
第5章 總結與未來工作 74
5.1 總結 74
5.2 未來工作 75
第6章 參考文獻 77
附錄A：誤差分析 82

[1] Laboratory, L. L. N., 2016, "Energy, Water, and Carbon Informatics," https://flowcharts.llnl.gov/.
[2] S. Rahman, 2003, "What is it and where can we find it?," Power and Energy Magazine, pp. 30-37.
[3] Lai, C.-C., Chang, W.-C., Hu, W.-L., Wang, Z. M., Lu, M.-C., and Chueh, Y.-L., 2014, "A solar-thermal energy harvesting scheme: enhanced heat capacity of molten HITEC salt mixed with Sn/SiO x core–shell nanoparticles," Nanoscale, 6(9), pp. 4555-4559.
[4] Medrano, M., Gil, A., Martorell, I., Potau, X., and Cabeza, L. F., 2010, "State of the art on high-temperature thermal energy storage for power generation. Part 2—Case studies," Renewable and Sustainable Energy Reviews, 14(1), pp. 56-72.
[5] Kearney, D., Herrmann, U., Nava, P., Kelly, B., Mahoney, R., Pacheco, J., Cable, R., Potrovitza, N., Blake, D., and Price, H., 2003, "Assessment of a molten salt heat transfer fluid in a parabolic trough solar field," Journal of solar energy engineering, 125(2), pp. 170-176.
[6] Sharma, S. D., and Sagara, K., 2005, "Latent heat storage materials and systems: a review," International Journal of Green Energy, 2(1), pp. 1-56.
[7] Jegadheeswaran, S., and Pohekar, S. D., 2009, "Performance enhancement in latent heat thermal storage system: a review," Renewable and Sustainable Energy Reviews, 13(9), pp. 2225-2244.
[8] Sharma, A., Tyagi, V., Chen, C., and Buddhi, D., 2009, "Review on thermal energy storage with phase change materials and applications," Renewable and Sustainable energy reviews, 13(2), pp. 318-345.
[9] Steinmann, W.-D., and Tamme, R., 2008, "Latent heat storage for solar steam systems," Journal of Solar Energy Engineering, 130(1), p. 011004.
[10] Prakash, J., Garg, H., and Datta, G., 1985, "A solar water heater with a built-in latent heat storage," Energy conversion and management, 25(1), pp. 51-56.
[11] Velraj, R., Seeniraj, R., Hafner, B., Faber, C., and Schwarzer, K., 1999, "Heat transfer enhancement in a latent heat storage system," Solar energy, 65(3), pp. 171-180.
[12] Farid, M. M., Khudhair, A. M., Razack, S. A. K., and Al-Hallaj, S., 2004, "A review on phase change energy storage: materials and applications," Energy conversion and management, 45(9), pp. 1597-1615.
[13] Hawlader, M., Uddin, M., and Khin, M. M., 2003, "Microencapsulated PCM thermal-energy storage system," Applied energy, 74(1), pp. 195-202.
[14] Cingarapu, S., Singh, D., Timofeeva, E. V., and Moravek, M. R., 2014, "Nanofluids with encapsulated tin nanoparticles for advanced heat transfer and thermal energy storage," International Journal of Energy Research, 38(1), pp. 51-59.
[15] Eastman, J. A., Choi, S., Li, S., Yu, W., and Thompson, L., 2001, "Anomalously increased effective thermal conductivities of ethylene glycol-based nanofluids containing copper nanoparticles," Applied physics letters, 78(6), pp. 718-720.
[16] Masuda, H., Ebata, A., and Teramae, K., 1993, "Alteration of thermal conductivity and viscosity of liquid by dispersing ultra-fine particles. Dispersion of Al2O3, SiO2 and TiO2 ultra-fine particles."
[17] Chandrasekar, M., Suresh, S., and Bose, A. C., 2010, "Experimental investigations and theoretical determination of thermal conductivity and viscosity of Al 2 O 3/water nanofluid," Experimental Thermal and Fluid Science, 34(2), pp. 210-216.
[18] Li, S., and Eastman, J., 1999, "Measuring thermal conductivity of fluids containing oxide nanoparticles," J. Heat Transf, 121(2), pp. 280-289.
[19] Wang, X., Xu, X., and S. Choi, S. U., 1999, "Thermal conductivity of nanoparticle-fluid mixture," Journal of thermophysics and heat transfer, 13(4), pp. 474-480.
[20] Xie, H., Wang, J., Xi, T., Liu, Y., Ai, F., and Wu, Q., 2002, "Thermal conductivity enhancement of suspensions containing nanosized alumina particles," Journal of Applied Physics, 91(7), pp. 4568-4572.
[21] Murshed, S., Leong, K., and Yang, C., 2005, "Enhanced thermal conductivity of TiO 2—water based nanofluids," International Journal of Thermal Sciences, 44(4), pp. 367-373.
[22] Hong, T.-K., Yang, H.-S., and Choi, C., 2005, "Study of the enhanced thermal conductivity of Fe nanofluids," Journal of Applied Physics, 97(6), p. 064311.
[23] Namburu, P., Kulkarni, D., Dandekar, A., and Das, D., 2007, "Experimental investigation of viscosity and specific heat of silicon dioxide nanofluids," Micro & Nano Letters, 2(3), pp. 67-71.
[24] Lu, M.-C., and Huang, C.-H., 2013, "Specific heat capacity of molten salt-based alumina nanofluid," Nanoscale research letters, 8(1), p. 292.
[25] Shin, D., and Banerjee, D., 2011, "Enhanced specific heat of silica nanofluid," Journal of heat transfer, 133(2), p. 024501.
[26] Ho, M. X., and Pan, C., 2014, "Optimal concentration of alumina nanoparticles in molten Hitec salt to maximize its specific heat capacity," International Journal of Heat and Mass Transfer, 70, pp. 174-184.
[27] Hong, Y., Wu, W., Hu, J., Zhang, M., Voevodin, A. A., Chow, L., and Su, M., 2011, "Controlling supercooling of encapsulated phase change nanoparticles for enhanced heat transfer," Chemical Physics Letters, 504(4), pp. 180-184.
[28] Tang, X., Li, W., Shi, H., Wang, X., Wang, J., and Zhang, X., 2013, "Fabrication, characterization, and supercooling suppression of nanoencapsulated n-octadecane with methyl methacrylate–octadecyl methacrylate copolymer shell," Colloid and Polymer Science, 291(7), pp. 1705-1712.
[29] Yamagishi, Y., Sugeno, T., Ishige, T., Takeuchi, H., and Pyatenko, A. T., "An evaluation of microencapsulated PCM for use in cold energy transportation medium," Proc. Energy Conversion Engineering Conference, 1996. IECEC 96., Proceedings of the 31st Intersociety, IEEE, pp. 2077-2083.
[30] Lin, C., Lai, Y., and Liu, S., 2001, "Effect of the surface roughness of sulfuric acid-anodized aluminum mold on the interfacial crystallization behavior of isotactic polypropylene," Journal of adhesion science and technology, 15(8), pp. 929-944.
[31] Wagner, M., and Widmann, G., 2009, Thermal analysis in practice, Mettler-Toledo.
[32] Kostic, M., and Simham, K. C., "Computerized, transient hot-wire thermal conductivity (HWTC) apparatus for nanofluids," Proc. Proceedings of the 6th WSEAS International Conference on HEAT and MASS TRANSFER (HMT’09), Citeseer, pp. 71-78.
[33] Bartzsch, H., Glöß, D., Böcher, B., Frach, P., and Goedicke, K., 2003, "Properties of SiO 2 and Al 2 O 3 films for electrical insulation applications deposited by reactive pulse magnetron sputtering," Surface and Coatings Technology, 174, pp. 774-778.
[34] Haarman, J., 1971, "A contribution to the theory of the transient hot-wire method," Physica, 52(4), pp. 605-619.
[35] Healy, J., De Groot, J., and Kestin, J., 1976, "The theory of the transient hot-wire method for measuring thermal conductivity," Physica B+ C, 82(2), pp. 392-408.
[36] Nagasaka, Y., and Nagashima, A., 1981, "Absolute measurement of the thermal conductivity of electrically conducting liquids by the transient hot-wire method," Journal of Physics E: Scientific Instruments, 14(12), p. 1435.
[37] Carslaw, H. S., and Jaeger, J. C., 1959, "Conduction of heat in solids," Oxford: Clarendon Press, 1959, 2nd ed., 1.
[38] Serway, R. A., and Jewett, J. W., 1998, Principles of physics, Saunders College Pub. Fort Worth, TX.
[39] Coleman, H. W., and Steele, W. G., 1989, "Experimentation and uncertainty analysis for engineers. John Wiley & Sons," New York.
[40] Limited, C. R., 2002, "Titanium Dioxide - Titania ( TiO2)," http://www.azom.com/properties.aspx?ArticleID=1179.
[41] Lucideon, 2001, "Alumina - Aluminium Oxide - Al2O3 - A Refractory Ceramic Oxide," http://www.azom.com/article.aspx?ArticleID=52.
[42] Chang, C.-C., 2016, "Influence of Different Oxide Shells on Phase Change Behavior of Encapsulated Zn Microparticles,"M.S. thesis, National Tsing Hua University.
[43] Chu, Y.-d., 2015, "Specific Heat Capacity and Thermal Conductivity of Molten Salt Doped with Micro and/or Nano Particles,"M.S. Thesis, National Chiao Tung University.
[44] Hoffman, J. D., and Weeks, J. J., 1962, "Melting process and the equilibrium melting temperature of polychlorotrifluoroethylene," J Res Natl Bur Stand A, 66(1), pp. 13-28.
[45] Nieto de Castro, C., Li, S., Nagashima, A., Trengove, R., and Wakeham, W., 1986, "Standard reference data for the thermal conductivity of liquids," Journal of physical and chemical reference data, 15(3), pp. 1073-1086.
[46] Santini, R., Tadrist, L., Pantaloni, J., and Cerisier, P., 1984, "Measurement of thermal conductivity of molten salts in the range 100–500 C," International journal of heat and mass transfer, 27(4), pp. 623-626.
[47] Perkins, R., Roder, H., and de Castro, C. N., 1991, "A high-temperature transient hot-wire thermal conductivity apparatus for fluids," Journal of research of the National Institute of Standards and Technology, 96(3), p. 247.
[48] de Castro, C. N., Perkins, R., and Roder, H., 1991, "Radiative heat transfer in transient hot-wire measurements of thermal conductivity," International journal of thermophysics, 12(6), pp. 985-997.
[49] Wang, X.-Q., and Mujumdar, A. S., 2007, "Heat transfer characteristics of nanofluids: a review," International journal of thermal sciences, 46(1), pp. 1-19.
[50] Myers, P. D., Alam, T. E., Kamal, R., Goswami, D., and Stefanakos, E., 2016, "Nitrate salts doped with CuO nanoparticles for thermal energy storage with improved heat transfer," Applied Energy, 165, pp. 225-233.
[51] Zhang, Z., Yuan, Y., Ouyang, L., Sun, Q., Cao, X., and Alelyani, S., 2017, "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(3), pp. 1783-1792.
[52] Silverman, M., and Engel, J., 1977, "Survey of technology for storage of thermal energy in heat transfer salt," Oak Ridge National Lab., Tenn.(USA).
[53] Tufeu, R., Petitet, J., Denielou, L., and Le Neindre, B., 1985, "Experimental determination of the thermal conductivity of molten pure salts and salt mixtures," International journal of thermophysics, 6(4), pp. 315-330.
[54] Balandin, A. A., Ghosh, S., Bao, W., Calizo, I., Teweldebrhan, D., Miao, F., and Lau, C. N., 2008, "Superior thermal conductivity of single-layer graphene," Nano letters, 8(3), pp. 902-907.