弥散核燃料等效辐照肿胀计算模拟

摘要

The dispersion nuclear fuel was regarded as a kind of special particle compos‐ites .Assuming that the fuel particles are periodically distributed in the dispersion nucle‐ar fuel meat ,the finite element model to calculate its equivalent irradiation swelling was developed with the method of computational micro‐mechanics .Considering irradiation swelling in the fuel particles and the irradiation hardening effect in the metal matrix ,the stress update algorithms were established respectively for the fuel particles and metal matrix .The corresponding user subroutines were programmed ,and the finite element simulation of equivalent irradiation swelling for the fuel meat was performed in Abaqus . The effects of the particle size and volume fraction on the equivalent irradiation swelling were investigated ,and the fitting formula of equivalent irradiation swelling was obtained .The results indicate that the main factors to influence equivalent irradiation swelling of the fuel meat are the irradiation swelling and volume fraction of fuel particles .%本文将弥散核燃料芯体看作一种特殊的颗粒复合材料，利用细观计算力学的方法，假设燃料颗粒在芯体中周期性分布，建立了对芯体等效辐照肿胀进行计算模拟的有限元模型。考虑颗粒的辐照肿胀和基体材料的辐照硬化效应，分别建立了燃料颗粒和基体材料的应力更新算法，编制了用户材料子程序，在A baqus软件中实现了芯体等效辐照肿胀的有限元模拟。计算分析了颗粒大小和体积含量对芯体等效辐照肿胀的影响，并得到了等效辐照肿胀的拟合公式。研究结果表明，影响芯体等效辐照肿胀的主要因素是颗粒的辐照肿胀和体积含量。