导热油与沙砾混合物斜温层单罐蓄热特性  

Thermal Energy Storage Characteristics of Synthetic Oil and Sand Mixture for Thermocline Single Tank

作　　者：杨勇平[1] 汉京晓[1] 李沛文[2] 徐犇[2] 侯宏娟[1] 

机构地区：[1]华北电力大学能源动力与机械工程学院,北京市昌平区102206 [2]亚利桑那大学航空与机械工程系

出　　处：《中国电机工程学报》2015年第3期631-637,共7页Proceedings of the CSEE

基　　金：国家自然科学基金资助项目(51206049;51025624);国家863高技术基金项目(2012AA050604);美国能源部资助项目(DE-AC04-94AL85000)~~

摘　　要：提出使用浸润了导热油的砂砾作为填料,以获取更好的斜温层单罐显热蓄热效果的思路。对Xceltherm 600型导热油与沙砾混合物在不同入口温度和流速下的蓄热特性进行研究。建立了间接接触式显热蓄热实验台,选用空气作为换热流体,流经钢管内部形成的通道换热,钢管外部与罐体内的蓄热混合物紧密接触。结果表明,与纯沙砾蓄热材料相比,导热油与沙砾混合物的蓄热效率能够提高18.5个百分点,且蓄热介质内部沿径向温度梯度更小,斜温层轴向温度梯度更大。不同的空气入口温度（328.15~358.15K）,对于罐体蓄热性能影响不大,但实际电站运行的最优温度区间仍有待研究。流速也是影响罐体蓄热性能的重要指标,低流速下不仅蓄热效率提高,而且斜温层的温度梯度也会增大。The new idea of using sand soaked with the thermal conductive oil as the filler material was proposed for better sensible heat storage in a thermocline single tank. The characteristics of thermal energy storage（TES） using the mixture of Xceltherm 600 synthetic oil and sand under various inlet temperature and velocities were investigated. An experimental setup of the TES system was built for the study. Air was used as the heat transfer fluid to flow through tubes that pass through the sand-oil mixture to store or extract heat. The outer surfaces of the airflow tubes have nice contact to oil and sand. It is found that the TES efficiency of sand-oil mixture increases by 18.5% compared to that of pure sand. In the sand-oil media, the temperature gradient along the radial direction is lower, while the temperature gradient along the axial direction is higher. Under the tested air inlet temperatures（328.15-358.15K）, the TES performances show similar characteristics. For industrial power generation application, further work to optimize temperature range needs to be conducted in the future. The air velocity is also another important parameter to the TES. Lower velocity not only increases the TES efficiency, but also enlarges the thermocline temperature gradient.

关 键 词：沙砾 太阳能 蓄热 填料 导热油 

分 类 号：TK512[动力工程及工程热物理—热能工程]