采用不同传热工质的锥形腔式吸热器传热特性对比分析  

Comparative Analysis of Heat Transfer Characteristics of Conical Cavity Receivers With Different Heat Transfer Fluids

作　　者：王鼎 陈宇轩 肖虎 张燕平[1] WANG Ding;CHEN Yuxuan;XIAO Hu;ZHANG Yanping(School of Energy and Power Engineering,Huazhong University of Science and Technology,Wuhan 430074,Hubei Province,China)

机构地区：[1]华中科技大学能源与动力工程学院,湖北省武汉市430074

出　　处：《发电技术》2021年第6期682-689,共8页Power Generation Technology

基　　金：国家重点研发计划项目(2018YFE0127500);湖北省技术创新专项(2019AAA017)。

摘　　要：为探究传热工质对太阳能吸热器传热特性的影响,利用光线追踪和计算流体动力学方法,对采用超临界CO_(2)和压缩空气作为传热工质的锥形腔体吸热器的传热特性进行对比分析。基于数值模拟讨论了吸热器锥角、工质进口流量和进口温度对吸热器传热性能的影响规律。结果表明:相同工况下,压缩空气的出口温度比超临界CO_(2)高,但相应的吸热器热效率和系统光热转化效率却较低。对于2种传热工质,系统光热转化效率均在锥角为4.12°时取得最优值。在研究的运行参数范围内,传热工质的出口温度随进口温度的增加呈线性增长;当流量超过0.04 kg/s时,继续增大流量对提高系统光热转化效率作用较小。To explore the influence of heat transfer fluids on the heat transfer characteristics of solar receivers,the heat transfer characteristics of conical cavity receivers with supercritical CO_(2) and compressed air as heat transfer fluids were compared and analysed by combining ray tracing and computational fluid dynamics method.Based on numerical simulation,the effects of cone angle,fluid inlet mass flow rate and inlet temperature on heat transfer performance of receivers were discussed.The results show that under the same working conditions,the outlet temperature of compressed air is higher than that of supercritical CO_(2),but the corresponding receiver thermal efficiency and system photothermal conversion efficiency are lower.For the two heat transfer fluids,the system photothermal conversion efficiencies reach the optimal values with the cone angle of 4.12°.In the range of operating parameters studied,the outlet temperature of heat transfer fluids increase linearly with the increase of inlet temperature.Once the mass flow rate exceeds 0.04 kg/s,increasing the mass flow rate has little effect on improving the photothermal conversion efficiency of the system.

关 键 词：太阳能 吸热器 超临界CO_(2) 压缩空气 传热特性 

分 类 号：TK513[动力工程及工程热物理—热能工程]