超临界二氧化碳（S-CO2）闭式布雷顿循环发电在能源领域展现出一定优势，而S-CO2物性准确快速计算直接关系到系统和部件的热力设计及压缩机和透平气动性能的准确预测。本文建立了高效模拟S-CO2物性的表格计算体系，包括表格自生成、索引查找及不同插值算法，提出了有效表格的通用制作方法，结合S-CO2等压比热和密度变化规律，研究了双线性、双立方和B样条插值方法计算特征，并对比了不同表格分辨率影响程度和各方案计算耗时。结果表明：物性表格计算的高误差主要分布在饱和线附近；双立方插值在全域平均误差最小，数量级在E-4至E-3间，B样条插值沿饱和线平均误差最低，最大误差数量级仅在E-2；表格分辨率取401×401可兼顾计算成本和求解精度；基于物性表格方案计算耗时远低于采用REFPROP数据库。

Supercritical carbon dioxide (S-CO2) Closed Brayton Cycle power generation shows certain advantages in the energy field. Whereas, accurate and rapid calculation of S-CO2 physical properties is directly related to the thermal design of systems and components and the accurate prediction of aerodynamic performance of compressors and turbines. In this paper, the table calculation system for efficiently modeling the physical properties of S-CO2 is established, including table self-generation, index search and different interpolation algorithms. A general method of making effective tables is put forward. Combined with the rule of variation of S-CO2 isobaric specific heat and density, the calculation characteristics of bilinear, bicubic and B-spline interpolation methods are studied. Moreover, the influence degree of different table resolutions and the calculation time of each scheme are compared. The results show that the high error of physical property table calculation is mainly distributed near the saturation line, the average error of bicubic interpolation is the smallest in the whole region, with the order of magnitude between E-4 and E-3. While the average error of B-spline interpolation along the saturation line is the lowest with the largest error of only E-2. The resolution of the table is 401×401, which can give consideration to both calculation cost and solution accuracy; The calculation time based on physical property table scheme is much less than that using REFPROP database.

上海空间推进研究所创新基金(17DZ2280800)