Off‐design performance and operation strategy of expansion process in compressed air energy systems
Off‐design performance and operation strategy of expansion process in compressed air energy systems
复制标题
DOI：
10.1002/er.4284
复制
发表时间：
2018-11
影响因子：
4.6
通讯作者：
Huan Guo;Yujie Xu;Yi Zhang;Cong Guo;Jianting Sun;Xinjing Zhang;Wen Li;Haisheng Chen
中科院分区：
文献类型：
--
作者：
Huan Guo;Yujie Xu;Yi Zhang;Cong Guo;Jianting Sun;Xinjing Zhang;Wen Li;Haisheng Chen
由于负荷波动、环境因素和系统的性能特点，压缩空气储能系统通常在非设计条件下运行。为了优化CAES系统的设计和运行，研究变工况性能具有重要意义。扩张过程在整个系统中起着重要的作用。本研究的主要目的是探讨蓄热式CAES系统多级膨胀过程的变工况特性及优化策略。首次提出并比较了等功率比(EPR)运行和优化定子叶片旋转角(OVRA)运行两种变工况。揭示了总输出功率比、(火用)效率、出口风水温度与质量流量比、进口压力等关键参数之间的关系。在此基础上，给出了最优运行原则。优化操作的主要原则是优化低压段的等熵效率，以提高膨胀过程的整体效率。最后，用多项式的形式给出了可变静叶的优化调节规律。
Compressed air energy storage (CAES) systems usually operate under off‐design conditions due to load fluctuations, environmental factors, and performance characteristics of the system. In order to optimize design and operation of CAES systems, it is significant to study off‐design performance. The expansion process plays an important role in the whole system. The main objective of this study is to explore the off‐design characteristics and optimization strategy of the multistage expansion process of CAES systems with thermal storage. Two kinds of off‐design operating modes, which are equal‐power‐ratio (EPR) operation and optimizing variable stator vane rotation angle (OVRA) operation, are proposed and compared for the first time. Correlation between key parameters such as total output power ratio, exergy efficiency, outlet air/water temperature versus mass flow rate ratio, and inlet pressure are revealed. Furthermore, optimal operation principles are obtained. The primary optimizing operation principle is to optimize the isentropic efficiencies of low‐pressure stages to improve the whole efficiency of expansion process. Lastly, the optimized regulating law for variable stator vane is expressed in a polynomial form.