燃料棒性能分析软件JASMINE中裂变气体释放模型的评估

Assessment of Fission Gas Release Model in Fuel Rod Performance Analysis Code JASMINE

裂变气体释放是燃料棒堆内安全运行必须考虑的关键行为。为了准确预测燃料棒中裂变气体释放行为,基于燃料棒性能分析软件JASMINE,集成了经典的Forsberg-Massih模型,并开发了两阶段裂变气体释放模型JASGAS,考虑晶界气泡重溶效应的影响,释放前后阶段的晶粒内部和晶界气体浓度变化。利用核燃料试验项目测量数据对模型进行评估,验证了模型的有效性。结果表明:在稳态工况下,JASGAS裂变气体释放模型预测较为准确,偏差较小;瞬态工况下,预测稍有偏低。

The fission gas release (FGR) is a crucial phenomenon, necessarily taken into account in the in-pile operation of the fuel rod. In order to predict accurately the fission gas release behavior of the fuel rod, based on the fuel rod performance analysis code JASMINE, incorporated the Forsberg-Massih model, and a two-stage FGR model, named JASGAS, was developed. The JASGAS model considers the grain boundary resolution effect, and the gas concentration variations inside the grain and at the grain boundary before and after the release. Some experimental data from fuel rod test project was used to evaluate the FGR models. The comparison results show that the JASGAS model predicts well under the steady-state conditions, and slightly under-predict under the transient conditions.