本論文研究儲存太陽熱能於相變化材料(Phase Change Material, PCM)之潛熱儲能系統設計，其中包括相變化材料的選擇、儲熱槽設計、系統儲熱效能等，研究中探討系統儲熱時相變化材料完成相變化過程所需之儲熱及放熱時間、儲熱系統熱傳行為、相變溫度範圍及PCM兩相介面移動影響系統效能等要素。本研究選擇熔點約94.7°C之木糖醇做為相變化儲熱材料，實驗系統以垂直殼管型儲存槽及熱傳油迴路構成，並設計真空外壁，利用真空及空氣的低熱傳特性減少熱散失。進行數次實驗，測試系統與相變化材料儲熱穩定性、分析靜置後熱散百分比、不同提熱溫度之效率，並輔以儲熱系統熱傳模擬，解析相變化材料內部溫度變化，並與實驗結果作比較。研究結果顯示儲熱效率大約在75%到90%之間，儲熱系統於環境溫度下靜置兩小時熱散量穩定在7%上下，提熱方面，應用60°C作為提熱溫度之效率最高(69.1%)，提熱溫度越高效率越差。

The Phase Change Material (PCM) latent heat Thermal Energy Storage (TES) systems for variety of applications such as solar thermal energy storage had received extensive research interesting for a decade. Some factors affect the system performance, such as the phase change materials, the thermal energy storage and the PCM container design, charging and discharging time, temperature range and propagation of the solid-liquid interface of PCM. This study investigated the performance of latent heat thermal energy storage by using CFD simulation and experimental methods. The results show the charging efficiency about 75% to 85%, and the heat loss almost 7% in two hours. During the discharging state of the TES system, the results show the efficiency at lower temperature was better than at higher temperature.

參考文獻
[1] K. Pillai and B. Brinkworth "The storage of low grade thermal energy using phase change materials," Applied Energy, vol. 2, pp. 205-216, 1976.
[2] A. Sharma, V. Tyagi, C. Chen, and D. Buddhi "Review on thermal energy storage with phase change materials and applications," Renewable and Sustainable energy reviews, vol. 13, pp. 318-345, 2009.
[3] G. A. Lane "Solar heat storage: latent heat materials," CRC Press, Boco Raton, FL, 1983.
[4] D. Morrison and S. Abdel-Khalik "Effects of phase-change energy storage on the performance of air-based and liquid-based solar heating systems," Solar Energy, vol. 20, pp. 57-67, 1978.
[5] A. Ghoneim "Comparison of theoretical models of phase-change and sensible heat storage for air and water-based solar heating systems," Solar Energy, vol. 42, pp. 209-220, 1989.
[6] M. Telkes and E. Raymond "Storing solar heat in chemicals," Ind. Heat. Engr.;(), vol. 12, 1950.
[7] H. G. Lorsch, K. W. Kauffman, and J. C. Denton "Thermal energy storage for solar heating and off-peak air conditioning," Energy conversion, vol. 15, pp. 1-8, 1975.
[8] J. E. Hill, E. R. Streed, G. E. Kelly, J. C. Geist, and T. Kusuda "Development of proposed standards for testing solar collectors and thermal storage devices," National Bureau of Standards, Washington, DC (USA). Center for Building Technology1976.
[9] D. Neeper "Thermal dynamics of wallboard with latent heat storage," Solar energy, vol. 68, pp. 393-403, 2000.
[10] A. El-Sebaii, A. Al-Ghamdi, F. Al-Hazmi, and A. S. Faidah "Thermal performance of a single basin solar still with PCM as a storage medium," Applied Energy, vol. 86, pp. 1187-1195, 2009.
[11] R. Domanski, A. El-Sebaii, and M. Jaworski "Cooking during off-sunshine hours using PCMs as storage media," Energy, vol. 20, pp. 607-616, 1995.
[12] S. Sharma, T. Iwata, H. Kitano, and K. Sagara "Thermal performance of a solar cooker based on an evacuated tube solar collector with a PCM storage unit," Solar Energy, vol. 78, pp. 416-426, 2005.
[13] J. Yagi and T. Akiyama "Storage of thermal energy for effective use of waste heat from industries," Journal of Materials Processing Technology, vol. 48, pp. 793-804, 1995.
[14] H. Michels and R. Pitz-Paal "Cascaded latent heat storage for parabolic trough solar power plants," Solar Energy, vol. 81, pp. 829-837, 2007.
[15] A. Abhat "Low temperature latent heat thermal energy storage: heat storage materials," Solar energy, vol. 30, pp. 313-332, 1983.
[16] B. Horbaniuc, G. Dumitrascu, and A. Popescu "Mathematical models for the study of solidification within a longitudinally finned heat pipe latent heat thermal storage system," Energy Conversion and Management, vol. 40, pp. 1765-1774, 1999.
[17] A. Sari and K. Kaygusuz "Thermal energy storage system using stearic acid as a phase change material," Solar Energy, vol. 71, pp. 365-376, 2001.
[18] F. Agyenim, P. Eames, and M. Smyth "A comparison of heat transfer enhancement in a medium temperature thermal energy storage heat exchanger using fins," Solar Energy, vol. 83, pp. 1509-1520, 2009.
[19] B. Zivkovic and I. Fujii "An analysis of isothermal phase change of phase change material within rectangular and cylindrical containers," Solar energy, vol. 70, pp. 51-61, 2001.
[20] M. Esen, A. Durmuş, and A. Durmuş "Geometric design of solar-aided latent heat store depending on various parameters and phase change materials," Solar Energy, vol. 62, pp. 19-28, 1998.
[21] F. Agyenim, P. Eames, and M. Smyth "Heat transfer enhancement in medium temperature thermal energy storage system using a multitube heat transfer array," Renewable Energy, vol. 35, pp. 198-207, 2010.
[22] N. Bansal and D. Buddhi "An analytical study of a latent heat storage system in a cylinder," Energy conversion and management, vol. 33, pp. 235-242, 1992.
[23] F. Agyenim, N. Hewitt, P. Eames, and M. Smyth "A review of materials, heat transfer and phase change problem formulation for latent heat thermal energy storage systems (LHTESS)," Renewable and Sustainable Energy Reviews, vol. 14, pp. 615-628, 2010.
[24] S. Fischer, W. Heidemann, H. Müller-Steinhagen, B. Perers, P. Bergquist, and B. Hellström "Collector test method under quasi-dynamic conditions according to the European Standard EN 12975-2," Solar Energy, vol. 76, pp. 117-123, 2004.
[25] B. Fortunato, S. Camporeale, M. Torresi, and M. Albano "Simple mathematical model of a thermal storage with PCM," AASRI Procedia, vol. 2, pp. 241-248, 2012.
[26] A. Shukla, D. Buddhi, and R. Sawhney "Thermal cycling test of few selected inorganic and organic phase change materials," Renewable Energy, vol. 33, pp. 2606-2614, 2008.
[27]李聰盛, 國立成功大學能源研究中心 "拋物面槽式聚光系統測試報告, " 2014.