目前主流的热工水力系统分析程序采用一阶差分格式来离散基本守恒方程。一阶差分截断误差大，导致系统分析程序在模拟自然循环问题时计算精度不高。为提高计算精度，本文采用两流体双压力两相流模型高精度数值解法对Welander自然循环问题进行计算分析。数值结果表明，高精度数值解法能有效减小数值扩散，提高预测精度。
The first-order difference scheme is widely employed to discretize basic conservation equations in current main thermal-hydraulics analysis code. However, first-order difference scheme has the characteristics of large numerical truncation error and low calculation accuracy when simulating natural circulation. In this paper, the high-order accuracy numerical algorithm for two-fluid two-pressure model is used to simulate Welander natural circulation problem. Numerical results imply that high-order accuracy numerical algorithm could prevent excessive numerical diffusion effectively and improve the prediction accuracy, which demonstrates the advantage of using high-order schemes.
2021,43(7): 93-98 收稿日期：2020-08-04
DOI：10.3404/j.issn.1672-7649.2021.07.019
分类号：TL364
作者简介：巢飞(1990-),男,博士,主要从事核反应堆热工水力及安全分析工作
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