聚变堆第一壁连续W/Cu梯度材料的热工性能优化

Thermo-technical performance optimization on first wall in fusion reactor applied with continuous W/Cu functionally graded material

针对不同体积分布指数p的W/Cu连续功能梯度材料的偏滤器第一壁结构,采用有限元软件计算了8MW.m^(-2)稳态运行热加载以及等离子体破裂条件下1GW.m^(-2)热流冲击下的力学响应。相同稳态加载条件下,W/Cu连续功能梯度材料的最优分布指数与分层梯度材料存在较大差异,其最优等效应力比分层梯度材料要小26%,表现出更优异的性能。在热冲击响应过程中,连续梯度W/Cu材料塑性损伤随p值不同也存在较大变化,其最优p值与其稳态运行时热应力最优p值存在一定差异,从第一壁应用条件考虑,应综合选取,最佳p值在1.2附近。综合来看,连续梯度W/Cu材料具有更连续变化的热物理属性及力学性能,在聚变堆第一壁结构设计中具有更大的应用潜力。

The thermo-technical performance optimization on first wall in fusion reactor made by such continuous W/Cu graded material with different composition distribution parameter p was descrided The thermal/mechanical responses of the first wall mockup under steady-state heat loads of 8MW·m-2 and heat shock loads of 1GW·m-2 during plasma disruptions are computed numerically with the finite element method. Under the same steady heat load conditions, the optimized composition distribution parameter p for composition continuous W/Cu graded material is very different with that of previous quasi-continuous W/Cu graded material. A 26% reducing in thermal stress is observed for first wall with composition continuous W/Cu graded material, demonstrating a more excellent performance. In the process of heat shock, the damage degree measured by volume fraction of plastic deformation is changing with different composition distribution parameter p, its optimized value is different with that obtained in steady state conditions. In consideration of environment conditions endured by first wall, the optimized value should be chosen to be close to 1.2. In general, there is a more prominent advantage for composition continuous W/Cu graded material applied in first wall design of fusion reactor due to its continuous variation of thermal physical properties and mechanical properties.