导热增强相变温控复合系统效能优化研究

Incoordination between energy supply and use in the energy usage results in a large amount of energy waste. Since the phase change thermal storage owns lots of advantages, such as high storage density, small temperature fluctuations in storage heat release process and easy control, it becomes a hot topic at home and abroad. However, the thermal conductivity of the phase change material is small and energy storage and release require a long time, the energy storage efficiency is limited. Therefore, it is of great significance to study the heat transfer/regenerative mechanisms for reinforced phase change composite heat storage material and optimized design of efficient energy storage system. This project uses harmonic detection technology and femtosecond laser pump-probe technique as the main experimental methods to study the influence law of reinforced heat transfer methods, size, microscopic morphology and structure, porosity, density on the heat transfer/regeneration for reinforced phase change composite heat storage material. Numerical simulation and theoretical analysis are combined to build a theoretical model to optimize thermal design of reinforced phase change composite heat storage material, revealing the heat transfer/regenerative mechanisms for typical reinforced phase change composite heat storage system. Based on this content, evaluation methods and experimental platform for heat regenerative performance of heat storage system is to be constructed. Aims to actual application requirements, efficient and stable, economical and practical regenerative energy storage system optimization design is to be proposed, providing a scientific experimental evidence and theoretical support for optimized design and preparation of reinforced phase change composite heat storage materials and the corresponding optimized design of regenerative energy storage system.

能源利用中存在供能和耗能间的不协调，造成大量能量浪费。由于相变蓄热具有蓄热密度高、储热释热过程温度波动小、过程易控制等特点，成为国内外研究热点。但是相变材料热导率小，储能和释能时间长，降低了储能效率。因此研究导热增强相变复合储能材料的传/蓄热机理及高效储能系统优化设计具有十分重要意义。本项目以谐波探测技术及飞秒激光抽运探测技术为实验手段，研究强化传热方式、尺度、微观形貌及结构、孔隙率、密度等对导热增强复合相变蓄热材料传/蓄热能力的影响规律；结合数值模拟及理论分析，建立导热增强复合相变材料的优化设计理论模型，揭示典型导热增强复合相变传/蓄热机理；在此基础上构建蓄热系统储能效能评价方法及实验平台，针对实际应用需求，提出高效稳定、经济实用的蓄热储能系统优化设计方法。为导热增强相变复合材料的优化设计和制备、相应蓄热储能系统优化设计提供科学实验依据及理论支撑。

相变蓄热具有蓄热密度高、储热释热过程温度波动小、过程易控制等特点，成为国内外研究热点。本项目以实验为主导，理论分析与数值模拟为支撑，系统开展导热增强相变复合储能材料多维、尺度结构的热物性匹配及温控效能研究。项目严格按照任务书执行：为了满足课题涉及的材料热物性及接触热阻的精确表征，首先升级改造了飞秒激光抽运探测系统及3ω谐波谐波探测系统。通过测量各类材料的有效热导率及各类界面热阻，开展导热增强相变复合储能材料多维、尺度结构的热物性匹配研究。系统分析了材料体系组分、孔隙率、微观结构、形貌及界面热阻等对复合材料体系热物性及传/蓄热性能影响规律。采用直接算法与估算相结合，开展了导热增强相变复合储能材料体系优化设计与仿真模拟，对导热增强相变复合材料传热传质行为及导热增强相变复合材料与系统储能效能计算方法进行了优化研究。最后开展了导热增强相变储能器件及系统储能效能模拟实验方法、控制因素及优化设计方法研究。课题在微观热输运机理及数值模拟方法等方面取得部分创新成果，由此深化了对微纳相变蓄热及热输运过程的认识，推动了微尺度传热及相变蓄热领域的发展，为导热增强相变复合材料在储能、余热回收、建筑节能的充分应用及电力削峰填谷等方面的应用提供理论及实验数据支撑。以该课题研究为基础申请获批了中科院仪器研制项目的资助，研制的“多维跨尺度材料热性能分析仪”是目前国际上唯一一套可实现纳米到宏观各类一维纤维、二维薄膜及三维体材料热物性表征的仪器设备，不但为本课题的各类跨尺度材料热性能表征提供了关键的实验设备，同时也推动了谐波探测技术仪器化。该设备已成功入选中国科学院自助研制科研仪器名录，率先在中国科学院进行应用推广。共发表学术论文/报告10篇，其中SCI论文3篇，国际会议特邀报告2次，国际会议论文/报告4篇。担任国际会议分会主席1次。申请发明专利3项，获批专利3项。毕业博士1名，在读博士2名，硕士1名。