108 / 2021-04-06 09:30:08

Gp方法-新型脆性断裂评估准则在RPV结构完整性上的应用研究

脆性断裂,Gp方法,结构完整性

Gp方法-新型脆性断裂评估准则在RPV结构完整性上的应用研究

郑斌 ¹，刘晗 ²，谢海 ¹，石凯凯¹

（1.中国核动力研究设计院，成都 610213；2.EDF China，北京 100005；）

摘 要：随着全球核电站的延寿的需求的进一步加强，在相应的工程计算领域面临着新的挑战。在断裂力学研究领取，在过去的20年中，法国电力进行了大量工作，以使Griffith能量释放率方法适应工程领域。这项工作最初建立了一种新的弹性断裂理论，该理论是从Griffith方法扩展而来的。此后，EDF改进了该模型，使其基于多种要素，包括能量最小化原理，特定损伤模型的以及使用U型缺口来表示裂纹尖端等。

到目前为止，Gp方法已被开发为一种实际的工程应用方法，因此在FEA软件中相对容易实现。目前code_aster中已经集成了计算Gp方法相应的运算模块。从2018年开始，EDF与CNNC / NPIC合作进行Gp方法的工业应用的研究。首先双方在CT样品上进行了一个简单的基准比较测试，然后进一步进行了RPV的工业案例的计算。这些研究旨在证明Gp方法在工程和结构完整性领域的适用性。本文介绍了EDF和NPIC双方进行的简单案例和工业案例的基准工作取得的进展以及成果。

关键词：脆性断裂；Gp方法；结构完整性



Application of Gp Method-New Brittle Fracture Evaluation Criteria in RPV Structural Integrity

ZHENG Bin¹，LIU Han²，XIE Hai ¹，SHI Kaikai¹

（1. NPIC，Chengdu 610213；2.EDF China，Beijing 100005；）



ABSTRACT:With the life extension of NPPs world-wide, new challenges have emerged in engineering calculations. In the brittle fracture research field, a significant amount work has been performed over the past 20 years in France to adapt the historic Griffith energy release-rate approach to engineering space. A new elastic fracture theory is set up, extended from the Griffith approach. Within EDF R&D, Lorentz and Wadier have since then improved the model which is based on several ingredients including the application of an energy minimization principle, the definition of a specific damage model and the use of a notch to represent the crack.

Among other advantages, the Gp method has been developed as a true engineering approach and hence is relatively easy to implement in a FE software: it has already been implemented into code_aster developed by EDF R&D.

Beyond the application in France, and in the wake of a simple comparison benchmark launched in 2018 with CNNC/NPIC on a CT specimen, then a calculation on a RPV type geometry was performed. This work aims at working together on establishing a strong industrial basis to demonstrate applicability in engineering and structural integrity space.

The paper provides the progress achieved in the benchmark work and the results obtained in the frame of the work jointly led with CNNC/NPIC in the field.

Key words: Brittle fracture; Gp approach; structural integrity