通用高效高精度物性插值计算方法及应用研究

A General Efficient and High-Precision Physical Property Interpolation Calculation Method and Its Application

摘要: 针对核动力流体系统仿真对多工质、宽工况物性计算的高效高精度需求，解决传统数据库调用效率低、常规插值法相变区精度不足的工程痛点，本文开展多工质物性计算方法研究。提出多层次网格加密算法，针对相态边界线和低精度网格进行加密处理，生成高精度物性库。在此基础上，引入双线性插值模型对高精度物性库进行高效插值计算以快速获得高精度物性计算结果，并且开发了适用多工质的物性计算软件，以供专业热工工程师使用。计算结果表明，高精度插值方法在宽工况范围内，相比于美国国家标准与技术研究院(NIST)开发的REFPROP标准物性数据库，利用压力、温度作为自变量计算比焓和密度的相对误差小于1%，且计算效率具有明显优势。

Abstract: This paper studied the physical property calculation methods for multi-working fluids to meet the requirements of efficient and high-precision property computation in nuclear power fluid system simulations under multi-fluid and wide operating conditions, and to solve the engineering challenges including low efficiency of traditional database access and insufficient accuracy of conventional interpolation in the phase-change region. A multi-level grid refinement algorithm was proposed to refine the phase boundaries and low-precision grids, and a high-precision physical property database was generated. On this basis, a bilinear interpolation model was introduced to perform efficient interpolation on the high-precision database for rapid and accurate property results. Furthermore, a multi-working fluid physical property calculation software was developed for professional thermal engineers. The results show that, compared with the REFPROP standard database developed by the National Institute of Standards and Technology (NIST), the proposed high-precision interpolation method achieves relative errors of less than 1% for specific enthalpy and density calculated from pressure and temperature across a wide range of operating conditions, and exhibits significant advantages in computational efficiency.